Category: Case Studies

Fatal gas embolism during transurethral enucleation of the prostate with bipolar electrodes

June 6, 2011/by admin Z.9

In this report, we describe a case of gas embolism occurring during TUEB, which might have been induced by gas generated from the electrode.

Authors: Inokuchi, Go; Yajima, Daisuke; Hayakawa, Mutsumi; Sakuma, Ayaka; Makino, Yohsuke; Iwase, Hirotaro
Corresponding Author: Go Inokuchi, Department of Legal Medicine, Graduate School of Medicine, Chiba University, Chiba, Japan. Email: [email protected]

Introduction

Transurethral resection of the prostate (TURP) is the most common surgical treatment for benign prostatic hypertrophy. In recent years, however, new transurethral resection techniques, including transurethral resection of the prostate in saline (TURis) and transurethral enucleation with bipolar (TUEB) electrodes, have been developed to minimise surgical complications such as TURP syndrome, obturator nerve reflex and haemorrhage. Application of the TUEB procedure to clinical cases has only recently started (1).

During prostate surgery, gas embolism can occur as a complication of medical intervention and may lead to death (2). Consequently, it is vital to understand whether the specific cause of the gas embolism can be elucidated and meaningful feedback given to the medical community. In this report, we describe a case of gas embolism occurring during TUEB, which might have been induced by gas generated from the electrode.

Case report

Clinical course

A 72 year old man (72kg, 165cm) was scheduled to undergo TUEB for the treatment of benign prostate enlargement. Preoperative tests were unremarkable. The procedure was performed with the patient in the reverse Trendelenburg lithotomy position under spinal anaesthesia, and no problems with the induction of anaesthesia were noted. The patient was not wearing anti-embolic stockings. Thirteen minutes into the operation, the patient complained of epigastric discomfort and blood pressure gradually dropped to 73/48mmHg from 131/97 mmHg, but heart rate remained unchanged at 60-70 bpm.

After administration of a plasma substitute was started, blood pressure returned to between 80 and 100mmHg, and the operation proceeded without major bleeding from the bladder or prostate. There were no gas bubbles other than the gas generated from the electrodes seen in the surgical field on the surgical monitor during the procedure. Around 90 min later, enucleation of the prostate was completed. The surgeon then used a tissue morcellator to cut the resected prostate into small pieces. A few minutes after inserting　the morcellator into the bladder, the patient lost consciousness and the electrocardiogram was flat.

Cardiopulmonary resuscitation was performed and the patient was taken to the medical care center, but subsequently died. Immediate postmortem computed tomography (CT) showed a large volume of gas in the heart (both left and right ventricles and left and right atria), pulmonary artery, cerebral vessels, vessels around bladder and bladder. (Figs.1, 2)

Figure 1.

Figure 2.

Autopsy findings

On external examination, there were no remarkable findings. On internal examination, left and right atrial puncture clearly revealed the presence of gas which had been confirmed by CT prior to autopsy. The foramen ovale was closed and the heart showed no organic problem. In the bladder, the urethral orifice was enlarged and the residual prostate gland remained (weight 40g). Furthermore, there was no major blood vessel injury into which gas might have entered. Histological examination showed congestion of the heart, liver and kidney, but there were no specific findings. We concluded that the cause of death was air embolism.

Verification experiment

On autopsy, we resected part of the prostate taken from the cadaver using the resection apparatus used clinically in 10 L saline at room temperature. Resection took2 min and the gas generated was collected with a syringe in order to measure the amount. In our measurements, gas was generated at approximately 15 mL/min in resection mode (Fig. 3). No gas was generated in coagulation mode.

Figure 3.

Discussion

It is well known that gas embolism can occur during invasive diagnostic or therapeutic intervention (2). Gas embolism during TURP, however, is exceedingly rare and there are only a few case reports in the anesthesia and urology literature (3–8).

The mechanisms of gas generation discussed in previous reports are as follows.

・ Incorrect assembly of the bladder irrigation-resectoscope-drainage system: gas flows into the bladder due to reverse connection of the inflow and the outflow lines (6, 8)

・ Infusion of gas into the irrigation fluid used to rinse the bladder at the end of the procedure (Ellik’s evacuator or three-way Foley catheter) (3, 4)

・ Infusion of gas into the irrigation bag (5)

・ Inclusion of gas when the internal cylinder is inserted and removed (5)

・ Gas generation by an electrosurgical knife (5)

In the present case, neither the drain system nor Ellik’s evacuator had been employed during the procedure. In addition, it had been strictly confirmed that no gas was present in the irrigation bag. Tsou et al. considered the possibility that air embolism can be induced by infusion of gas generated from irrigation fluid that is vaporized by the electrical discharge of an electrode and by the infusion of gas into the bladder when the internal cylinder is inserted and removed (5). They did conclude, however, that the probability of a lethal volume of gas generated by such procedures is very low.

An electrosurgical knife resects tissue by arc discharge which is produced though the high-voltage potential formed at the part with the highest resistance value in the electrical circuit. While monopolar electrodes produce this arc discharge at the site of contact in the human body, bipolar electrodes (loop electrodes) generate a high voltage potential with gas bubble produced all around the electrodes, because normal saline has lower resistance than human tissue. For this reason, bipolar electrodes can generate more gas than when monopolar electrodes are used for conventional TURP (9).

In the present case, the ventral mucosa of the prostate adenoma was resected at an early stage. Therefore, it was thought that a vascular stump may have been exposed to gas over a clinically significant time period, so that avolume of gas could have entered and accumulated in the veins. However, Tsou et al. considered it doubtful that a lethal volume of gas could have been generated from an electrode. To address this question we conducted an experiment to elucidate the volume of gas that can be produced when resecting in saline with bipolar electrodes, observing that gas was generated at a rate of approximately 15mL/min. It has been reported that the lethal volume of air is approximately 200mL(10). This volume would be generated in 14 min in our observations; if a large proportion of the generated gas is taken up by the vascular system, sufficient volume may be accumulated intravascularly to cause death.

The patient’s complaint and the reduction of blood pressure shortly before cardiopulmonary arrest might have indicated that gas embolism had already developed at this point. Although gas embolism caused by the loop electrode may have been the decisive event, it might have been overlooked because the patient exhibited only minor symptoms and fatal cases are rare. Taken together, urologists should be aware of the possibility of gas embolism when a patient complains of discomfort or when there is a reduction in blood pressure during surgery.

References

1. Fagerström T, Nyman CR, Hahn RG. Bipolar transurethral resection of the prostate causes less bleeding than the monopolar technique: a single-centre randomized trial of 202 patients. BJU Int. 2010 Jun; 105(11):1560-4.

2. Mirski MA, Lele AV, Fitzsimmons L, Toung TJ. Diagnosis and treatment of vascular air embolism. Anesthesiology. 2007 Jan; 106(1):164-77.

3. Hofsess DW. Fatal air embolism during transurethral resection. J Urol. 1984 Feb; 131(2):355.

4. Vacanti CA, Lodhia KL. Fatal massive air embolism during transurethral resection of the prostate. Anesthesiology. 1991 Jan; 74(1):186-7.

5. Tsou MY, Teng YH, Chow LH, Ho CM, Tsai SK. Fatal air embolism during transurethral incision of the bladder neck under spinal anesthesia. Anesth Analg. 2003 Dec; 97(6):1833-4

6. Frasco PE, Caswell RE, Novocki D. Venous air embolism during transurethral resection of the prostate. Anesth Analg. 2004 Dec; 99(6):1864-6.

7. Fukano N, Sasaki J, Iida R, Ichihara Y, Suzuki T, Ogawa S. Pulmonary embolism induced by evacuator during transurethral resection of the prostate. Masui. 2007 Feb; 56(2):178-80.

8. Matsuno D, Cho S, Isshiki S, Kojima S, Sato N, Suzuki F, Furuya Y. A case of venous air embolism during transurethral resection of the prostate. Hinyokikakiyo. 2007 Jun; 53(6):409-11.

9. Ioritani N. The characteristics of TURis system and the techniques in TURBT. Jpn J

Urol Surg. 2008 Jun; 21(6):789-94.

10. Toung TJ, Rossberg MI, Hutchine GM. Volume of air in a lethal venous air embolism.Anesthesiology. 2001 Feb; 94(2):360-1.

Date added to bjui.org: 06/06/2011

DOI: 10.1002/BJUIw-2011-012-web

Urachal diverticulum as a cause of midline testicular ectopia

May 23, 2011/by admin Z.9

We present a case report of medline testicular ectopia caused by urachal diverticulum in a seven-year old boy.

Authors: M. A. El-Shazly MD, N. A. Al-Enezy, K. Shefagah. Urology Department,Farwaniya Hospital, Kuwait
Corresponding Author: Dr. M.A. El- Shazly, Urology Dept., El-Farawaniya Hospital, Kuwait. E-mail: [email protected]. Tel 00965 94453755

Abstract

We present a case report of medline testicular ectopia caused by urachal diverticulum in a seven-year old boy presented to our department with impalpable right undescended testis. The association of urachal diverticulum with midline testicular ectopia is an extremely rare finding. The ectopic testis was detected during diagnostic laparoscopy for unilateral right undescended testis. It was detected as a midline parietal structure adherent to the wall of urachal diverticulum. Open exploration was done and the tesis was dissected from the wall of urachal diverticulum. Orchiopexy was done with urachal diverticulectomy.

Abbreviations

(PMDS) Persistent mullerian duct structures

Introduction

The association of testicular ectopia with embryologic abnormality is reported in the literature particularly with persistent Mullerian duct structures (PMDS) that alter the pathway of normal testicular descent and may lead to transverse testicular ectopia to the contralateral inguinal canal [2].

Case Report

A seven year old boy presented to our department with impalpable right undescended testis. Examination did not reveal the right testis, but the right hemiscrotum was well-developed and there was a normal testis on the left side of scrotum. He had unrepaired coronal hypospadias. Ultrasonography revealed no testis in the right inguinal canal and an ectopic left kidney. The patient underwent diagnostic laparoscopy under general anaesthesia using a 5mm infra-umbilical port that revealed a vas and vessel entering the left internal ring. Surprisingly, we found a midline parietal structure on the anterior abdominal wall. The vas was detected proximally then became less developed near the testis in the abdominal wall. Open exploration through a midline sub-umbilical incision was then undertaken, that revealed small size testis just deep to the anterior abdominal wall, midway between the umbilicus and the symphysis pubis (Figure 1).

Figure 1. Midline parietal testicular ectopia

The testis was closely adherent to a well-developed sac; with further dissection, the sac was identified as a urachal diverticulum. The balloon of a foley catheter was felt easily after opening of the diverticulum (Figure 2).

Figure 2.Testis (White arrow) adherent to the wall of a urachal diverticulum

The testis was mobilized on a leash of vessels and the vas deferens, then positioned in a subdartos pouch. Classic urachal diverticulectomy was done with closure of the bladder in 2 layers over a suprapubic catheter for one week. Biopsy of the testis revealed normal testicular tissue.

Discussion

The urachus is a tubular structure lying between the foetal bladder and the umbilicus and is susceptible to complete or partial involution after birth. Persistence of the urachus results in a wide spectrum of anomalies: patent urachus, vesicourachal diverticulum, urachal sinus and cysts [1].

The association of testicular ectopia with an embryologic abnormality is reported in the literature, particularly with persistent Mullerian duct structures (PMDS) that alter the pathway of normal testicular descent and may lead to crossed testicular ectopia to the inguinal canal [2,3,4]. Midline ectopia is a rare site of testicular ectopia and should be considered during diagnostic laparoscopy if the testis is not found near the internal ring or over the iliac vessels [5].

However, to our knowledge, the association of urachal diverticulum with midline testicular ectopia was not previously reported in the literature. This case could be explained embryologically in a manner similar to the effect of PMDS. The urachal diverticulum interferes with the normal pathway of testicular descent and diverts the testis to the dome of the diverticulum just deep to the anterior abdominal wall.

It is crucially important to investigate for other urological congenital anomalies especially if the patient has both hypospadias and undescended testis. The association of coronal hypospadias, ectopic kidney, urachal diverticulum and undescended testis correlates a the multiplicity of urological congenital anomalies [6].

Conclusion

Urachal diverticulum is an extremely rare cause of midline testicular ectopia that could be explained embryologically.

References

1. Bergami G, Inserra A, Ciprandi G, Barbuti D, Di Mario M, Boglino C. Persistent multiple urachal complex. Echographic-surgical correlations. Minerva Chir. 1992,15;47(9):879-883

2. Thambidorai C & Khaleed A. Transverse testicular ectopia: correlation of embryology with laparoscopic findings. Pediatr Surg Int. 2008;24(3):371-4

3. Wuerstle M, Lesser T, Hurwitz R, Applebaum H, Lee S. Persistent mullerian duct syndrome and transverse testicular ectopia: embryology, presentation, and management. J Pediatr Surg.; 2007, 42(12):2116-2119

4. Ozturk H, Eroglu M, Ozturk H, Uzunlar A , Okur H Persistent Müllerian duct syndrome associated with transverse testicular ectopia: report of two cases. Fetal Pediatr Pathol. 2007, 26(1):41-46

5. Jordan G Laparoscopic management of the undescended testis. Urol clin North Am 2001. 28 (1): 23-29

6. Khatwa U , Menon P Management of undescended testis. Indian J Pediatr. 2000, 67(6):449-454

Date added to bjui.org: 23/05/2011

DOI: 10.1002/BJUIw-2011-026-web

Paraganglioma of the paratesticular area: an extremely rare location

May 17, 2011/by admin Z.9

We report a case of solitary primary paraganglioma in the paratesticular region, presenting with scrotal swelling and dull pain as the only symptoms.

Authors: Dr. Sufia Husain MBBS, MD, FRCPath, Senior Registrar (Histopathology Unit). Dept of Pathology

Dr. Emad Raddaoui MD, FCAP, FASC, Consultant Histopathologist (first author), King Khalid University Hospital, College of Medicine, King Saud University, Riyadh, Saudi Arabia.

Corresponding Author: Dr. Sufia Husain MBBS, MD, FRCPath, Senior Registrar (Histopathology Unit). Dept of Pathology, P.O. Box 2925, King Khalid University Hospital, College of Medicine, King Saud University, Riyadh-11472, Saudi Arabia. Tel: 00-9661-4671892. Email: [email protected]

Introduction

Paraganglia are aggregates of neuroendocrine cells, distributed throughout the body. Paragangliomas are unique neuroendocrine neoplasms arising from these specialized cells of neural crest origin. These tumours are usually located in the carotid body, the jugulo-tympanic body, the mediastinal vessels, or the abdomen, with the majority being benign. Although they have been described in virtually every organ, a paraganglioma at a paratesticular location is extremely rare. Only 8 cases have been reported to date. The clinical features of these tumours are variable, including hypertension, palpitations, headache, sweating, and other symptoms associated with increased catecholamine levels. We report a case of solitary primary paraganglioma in the paratesticular region, presenting with scrotal swelling and dull pain as the only symptoms. We also review in brief the clinical differential diagnosis, possible histogenesis, light microscopic features, immunohistochemistry and electron microscopy results, and general prognosis of the tumour.

Case report

A 35-year-oldSaudi man presented with an 11-month history of dull ache and dragging sensation in the scrotum, accompanied by a scrotal swelling. There was no history of fever, genital trauma, or genital infection. The patient denied having experienced nausea, vomiting, diarrhea, flushing, palpitations, or weight loss. His vital signs were normal, and the findings of a general physical examination were unremarkable. Examination of the scrotum revealed a right-sided non-tender mass with 3.0 cm being its largest diameter. There were no changes in the overlying skin, and no enlargement of the inguinal lymph nodes. The left side of the scrotum was normal. The complete blood count was normal, as were the levels of tumour markers such as alphafetoprotein, beta human chorionic gonadotrophin, and lactate dehydrogenase. Ultrasonography performed to further define the mass showed a well-circumscribed right paratesticular mass at the upper poleof the right testis, near the head of the epididymis. There was an associated mild varicocoele. The lesion did not involve the epididymis and testis. The right and left testicles were normal in size and echotexture. A chest radiograph and abdominal computed tomography scan showed no significant abnormalities. A provisional clinical diagnosis of a benign paratesticular mass was made, and the patient was counseled before exploratory surgery was performed under general anaesthesia. Tissue from the lesion was submitted for intra-operative frozen section pathologic analysis to enable a decision about testicular preservation. When the specimen was reported as a benign soft tissue tumourwith features consistent with paraganglioma, a testis-sparing operation was chosen. The mass was subsequently excised, but the right testicle and epididymis were not resected. Postoperative recovery was uneventful. The patient was discharged 5 days after surgery, with instructions for regular periodic follow-up with the urologist.

The specimen received in the laboratory was a well-encapsulated mass measuring 3.0 × 2.5 × 2.0 cm. Its external surface was smooth and slightly lobulated, with thin-walled blood vessels running across it. The cut surface was solid and yellowish with focal haemorrhagic areas and delicate septae coursing through it. The tissue was fixed in 10% neutral buffered formalin. Multiple sections were taken from the tissue and embedded in paraffin, cut into 5 micron thick slices, transferred to slides, and stained with haematoxylin and eosin. Unstained slides were also prepared for immunohistochemical study. Light microscopy revealed a tumour comprising cohesive lobules or nests of cells bound by delicate fibrovascular stroma arranged in a Zellballen pattern (Fig.1a). These nests of tumour cells were peripherally encircled by spindle-shaped sustentacular cells. The tumour cells were round to oval with abundant granular eosinophilic cytoplasm, speckled nuclear chromatin, and conspicuous nucleoli. The cells showed mild to moderate nuclear pleomorphism. Scattered multinucleated giant cells were present. Features like intracytoplasmic hyaline globules and eosinophilic intranuclear pseudoinclusions (Fig.1b) were also noted. Mitotic activity, although present, was no more frequent than 1 mitotic figure per 20 high power fields. Necrosis and lymphovascular invasion were absent.

The unstained slides were subjected to immunohistochemical analysis in the Leica Bond Max immunostainer (Vision BioSystems, Newcastle, UK) using the Bond Polymer Refine detection kit (a biotin-free, polymeric horseradish peroxidase-linker antibody conjugate system). The tissue was stained using antibodies against S-100, chromogranin, synaptophysin, CD 56, cytokeratin (CK), and vimentin. The tumour cells exhibited diffuse cytoplasmic positivity forsustentacular cells labeled with chromogranin (Fig.1c), synaptophysin, and CD 56. The sustentacular cells were labeled with S-100;therewere stellate and spindle-shaped cells found cuffing the Zellballen nests (Fig.1d). The tumour cells did not react with CK or vimentin. The Ki67/MIB-1 index was less than 2%.

Figure 1. (a) Photomicrograph showing a low power view of the tumor mass, exhibiting the classical nesting pattern called Zellballen architecture (hematoxylin-eosin, 200× magnification). (b) A higher magnification of the tumor shows cells with abundant eosinophilic cytoplasm and moderate nuclear pleomorphism. An intranuclear pseudoinclusion (arrow) is also noted (hematoxylin-eosin, 400× magnification). (c) The tumor cells reveal strong cytoplasmic positivity for chromogranin (400× magnification). (d)The sustentacular cells rimming the Zellballen nests are highlighted by the S-100 stain (400× magnification).

A small amount of paraffin-embedded tissue was submitted to the electron microscopy unit. On ultrastructural evaluation, numerous small dense secretory cytoplasmic granules measuring approximately 150 microns were identified (Fig. 2). The light microscopic, immunohistochemical, and electron microscopic features were thus all characteristic of paraganglioma. The absence of any other lesion elsewhere in the body, both clinically and radiologically, led to a final diagnosis of primary paratesticular paraganglioma.

Figure 2a and 2b. FIG. 2(a) Electron micrograph showing the characteristic multiple dark neurosecretory granules (black arrow) in the cytoplasm of the tumor cells. These are membrane-bound granules with an electron-dense core. (transmission electron microscope, 9000× magnification). (b) The neurosecretory granules are seen around the nucleus at a higher magnification. Also visible, is the rough endoplasmic reticulum (arrowhead) (transmission electron microscope, 28000× magnification).

Discussion

Scrotal paratesticular masses present a diagnostic dilemma to urologists. most paratesticular tumours are benign, about 30% are malignant [1]. Any scrotal mass therefore has to be adequately evaluated in order to rule out malignancy. Exploratory surgery with intraoperative histologic analysis of a frozen section is useful in surgical decision-making. Once the benign nature of the neoplasm is determined on frozen section, a testis-sparing surgical procedure can be performed, with the benefits of retaining the cosmetic and hormonal function of the organ. Common benign tumours of the paratesticular region include lipomas, adenomatoid tumours, leiomyomas, fibromas, papillary mesotheliomas, and cystadenomas [1]. Paragangliomas are extraordinarily rare at this site.

Paragangliomas are neuroendocrine neoplasms of neural crest origin composed of neuroepithelial chief cells. They occur in the fourth and fifth decades and are equally prevalent in both sexes [2]. Most paragangliomas are located in the adrenal gland, where they are referred to as pheochromocytomas. Extra-adrenal paragangliomas are found along the sympathetic and parasympathetic chains, where paraganglia are normally distributed. The common sites for extra-adrenal paragangliomas include the carotid body, vagal body, middle ear, abdomen (organ of Zuckerkandl), and the aortic-pulmonary and laryngeal areas [2].They have also been reported in certain unusual sites like the orbit [3], chambers of the heart, [4] and bone [5]. Paragangliomas have occasionally been reported in the urogenital tract, in the urinary bladder[6], and the prostate [7]. To our knowledge, only 8 cases have been reported worldwide in theliterature so far [8,9], with the first documented case of paratesticular paraganglioma described in 1971 by Eusebi et al. [10].

The histogenesis of paratesticular paragangliomas is a matter of debate. Paraganglia have been observed in the paratesticular tissue around the epididymis and spermatic cord in infancy [11, 12]. Rarely, heterotopic adrenal glands with medullae have also been documented along the route of descent of the testis into the scrotum [11,12]. As a rule, both the heterotopic gland and paraganglial tissue involute during childhood. In exceptional cases, they may persist and eventually harbour a neoplasm. It is our hypothesis that this may be the case in our patient.

These lesions can be functional or non-functional. In a functional lesion, the tumour secretes catecholamines and the presenting symptoms such as headache, sweating, palpitations, and hypertension are secondary to elevated levels of these hormones. Abdominal paragangliomas are more likely to be functional. Although our patient was not tested for catecholamine levels prior to surgery, his was clearly a case of a non-functional paraganglioma, since he displayed none of the symptoms associated with elevated catecholamines. Paragangliomas can also be hereditary or be seen in conjunction with neurofibromatosis type I, Von Hippel-Lindau disease, and multiple endocrine neoplasia type II. Our case had no such associations.

Most paragangliomas are benign, indolent tumours. Malignant lesions are rare, occurring in the fifth to seventh decade, and they tend to be more symptomatic than benign tumours. The diagnosis of malignancy is essentially based on the presence of distant metastasis. Capsular or lymphovascular invasion, a diffuse pattern, confluent tumour necrosis, atypical mitosis, increased mitotic activity (>3 mitotic figures/10 high power fields), fewer S-100 protein-positive sustentacular cells, and a high Ki-67 (MIB-1) index have all been postulated as indicators for predicting malignancy [2]. These indicators, however, are not reliable and cannot be used as well-established histologic criteria for malignancy. Therefore, the treatment of choice for a paraganglioma is complete surgical resectioncoupled with prolonged regular follow-up to rule out a recurrence or the development of metastases. Although there is no specific recommended follow-up strategy, our patient underwent 6 monthly follow-up examinations for the first 3 years and annual ones in the following 2 years. There was no clinical, biochemical, or radiological evidence of recurrence or metastases of the tumour in the 5 years after surgery.

In conclusion, we report a very rare case of non-functional primary paratesticular paraganglioma. We believe that despite their rareincidence in this region, they ought to be considered in the differential diagnosis of a paratesticular neoplasm. Radiological imaging alone is insufficient to determine the nature of a paratesticular mass. Scrotal exploration coupled with intraoperative frozen section analysis can be used as diagnostic tools to rule out the possibility of malignancy, and thus prevent overtreatment with orchidectomy. A diagnosis of paraganglioma is ultimately dependent on a complete and careful histopathological evaluation, in conjunction with consideration of the immunohistochemical findings. Electron microscopy can also be used to confirm the neuroendocrine nature of the neoplasm.

References

1. Khoubehi B, Mishra V, AliM, Motiwala H, Karim O. Adult paratesticulartumours. BJU International 2002;90:707-15.

2. Hunt J. Diseases of the paraganglia system.In: Thompson LDR, editor.Endocrine Pathology. In: Goldblum JR, series ed. Foundations in Diagnostic Pathology. 1st edn. Philadelphia, Churchill Livingstone Elsevier; 2006. p. 327-8.

3. Makhdoomi R, Nayil K, Santosh V, Kumar S. Orbital paraganglioma- a case report and review of literature. Clinical Neuropath. 2010 Mar-Apr;29(2):100-4.

4. Khalid TJ, Zuberi O, Zuberi L, Khalid I. A rare case of cardiac paraganglioma presenting as anginal pain: A case report.Cases J. [serial on the internet]. 2009 Jan 21; 2(1): [about 4 p.]. Available from:https://www.casesjournal.com/content/2/1/72.

5. Laufer I, Edgar MA, Hartl R. Primary intraosseous paraganglioma of the sacrum: a case report. Spine J. 2007; 7(6): 733-8.

6. Cheng L, Beltran AL, MacLennan GT, Montironi R, Bostwick DG.Neoplasms of the urinary bladder. In Bostwick D, Liang C,editors.Urologic Surgical Pathology, 2nd edn. Edinburgh: Mosby, Elsevier; 2008. P. 315-7.

7. Bostwick DG, Meiers I. Neoplasms of the prostate. In Bostwick D, Liang C, editors.Urologic Surgical Pathology, 2nd edn. Edinburgh: Mosby, Elsevier; 2008.p. 538.

8. Gupta R, Howell RS, Amin MB. Paratesticular paraganlioma: A rare cause of an intrascrotal mass. Arch Pathol Lab Med. 2009; 133(5): 811-3.

9. Garaffa G, Muneer A, Freeman A, et al. Paraganglioma of the spermatic cord: case report and review of the literature. Scientific World Journal 2008; 8: 1256-8.

10. Eusebi V, Massarelli G. Pheochromocytoma of the spermatic cord: report of a case. J Pathol. 1971; 105(4): 283-4.

11. Nistal M, Paniagua R. Non-neoplastic disease of the testis. In Bostwick D, Liang C, editors: Urologic Surgical Pathology, 2nd edn. Edinburgh: Mosby Elsevier; 2008. p. 622-3.

12. Petersen R, Sesterhenn IA, Davis CJ:Urologic Pathology, 3rd edn. Philadelphia: Lippincott Williams & Wilkins;2009. p. 413-4.

Date added to bjui.org: 17/05/2011

DOI: 10.1002/BJUIw-2011-036-web

Laparoscopic resection of an exophytic, enhancing renal mass: A case report of left-sided splenorenal fusion

May 11, 2011/by admin Z.9

We report a left-sided exophytic, enhancing renal mass that was found after surgery to be a case of splenorenal fusion.

Authors: Brian Shuch, Alberto Breda, Peter Schulam, David Geffen. School of Medicine at UCLA, Department of Urology

Corresponding Author: Peter Schulam, MD, PhD, 200 Med Plaza Suite 665, Los Angeles, CA 90095. E-mail: [email protected]

Abstract

The presence of splenic tissue contained within Gerota’s fascia is a rare finding that may be related to a developmental anomaly or secondary to splenosis. Its presence may mimic primary renal neoplasms or a metastatic lesion [1]. We report a rare case of splenorenal fusion that presented as an incidental 1.5 cm enhancing mass arising off the upper pole of the left kidney. A laparoscopic partial nephrectomy was planned; however, intra-operatively it was clear the mass was a separate entity contained within Gerota’s fascia. Final pathology revealed the presence of normal splenic tissue.

Introduction

Congenital and acquired splenic abnormalities are frequently encountered, with the most common being a supernumerary spleen, observed in up to 30% of the population. An accessory spleen can be located anywhere within the abdomen and pelvis; over 70% are found in the left upper quadrant [2]. The presence of additional splenic tissue can be problematic in patients who require splenectomy for medical disease, including hereditary spherocytosis or idiopathic thrombotic purpura. Despite a presumed curative splenectomy, patients with an unrecognized accessory spleen can develop disease recurrence. Splenosis, ectopic auto-transplanted splenic tissue, frequently occurs after a splenic injury. The incidence of splenosis varies by type of splenic insult and can develop in up to 20% of patients after splenectomy and in 67% of patients with splenic trauma [3].

Splenic fusion is a rare developmental anomaly of minimal clinical significance believed to derive from direct fusion of the spleen with retroperitoneal structures during development. Splenogonadal fusion is a frequently-described fusion anomaly having been reported over 150 times since its description over two hundred years ago [4]. This abnormality is associated with other developmental defects such as limb anomalies or facial defects [5].

There is debate whether splenosis of the renal fossa is a separate entity from splenorenal fusion. No theories currently account for how splenic tissue after trauma or splenectomy would migrate through the perirenal fat and Gerota’s fascia. In the absence of trauma or splenectomy, its presence is believed to represent a true splenorenal fusion likely resulting from splenic fusion to the metanephros during renal development [6].

We describe a rare case of left-sided splenorenal fusion that occurred in a young woman who underwent a left partial nephrectomy and was found with normal splenic tissue within Gerota’s fascia.

Case Report

A 53-year old obese female with a past history of hypertension presented to the emergency room with acute chest pain. She had no prior surgical history and no previous trauma. An electrocardiogram confirmed the presence of atrial fibrillation. A chest CT scan was performed to rule out a pulmonary embolism. Incidentally, the lower cuts of the scan demonstrated an enhancing left kidney mass. This exophytic 1.5 cm mass arose from the upper pole and extended posteriorly (Figure1).

Figure 1a. Left-sided upper pole, posterior mass

Figure 1b. Left-sided upper pole, posterior mass

After further staging, surgery was recommended and she opted for a laparoscopic partial nephrectomy. Coumadin was held prior to surgery and she was bridged with heparin.

The patient was placed under general anesthesia and positioned in the left flank position. Access and port placement with our technique have been described previously.[7] Sharp dissection was performed to reflect the colon and spleen medially. Upon entry into Gerota’s fascia, we noted an exophytic mass by the upper pole of the kidney. Blunt dissection carefully exposed the lesion and it soon became evident that the mass, while close to the renal capsule, was not in continuity. Once the mass was mobilized, the lower 5 mm trocar was replaced for a 10 mm trocar in order to extract the mass with a 10 mm EndoCatch bag. After re-inspection for haemostasis, all port sites were closed and the skin edges re-approximated.

The patient was stable throughout the case and transferred to a non-monitored floor. She was placed on clear liquid diet post-operatively and the foley catheter removed on the first morning. Her diet was advanced and she was discharged later on post-operative day 1. On gross pathologic exam the mass was a 1.1 x 0.8 x 0.6 cm red oval-shaped nodule and consistent with normal splenic tissue on microscopic exam.

Discussion

Only roughly a half dozen cases of splenorenal fusion have been described in the literature, mostly associated with the left kidney.[1, 8-11] However, Rosenthal and colleagues reported a large right-sided case of splenorenal fusion [6]. The presentation of splenorenal fusion varies from symptoms of hypersplenism to incidentally-discovered masses. Many of the previous reported cases resulted in a nephrectomy either for management of hypersplenism or for a suspicious renal mass. Fortunately our case was performed laparoscopically, with no unnecessary loss of renal parenchyma, and the patient required only an overnight hospital stay.

To avoid such a situation and a possible unnecessary radical or partial nephrectomy, correct preoperative identification of splenic tissue contained within Gerota’s fascia is required. As splenorenal fusion is a rare entity, it is likely that many clinicians would consider this in the differential and proceed with an operative intervention. However, in the setting of a prior splenectomy or trauma, there should be a moderate index of suspicion and it should be included in the differential of a very exophytic, enhancing left-sided renal mass. Clinicians can also stumble on this diagnosis due to the increased utilization of biopsies for small renal masses. However if normal splenic tissue is identified without any renal neoplasm, it is also possible that the biopsy needle has tracked through the normal spleen. In this case it would be of utmost importance to discuss the likelihood of this scenario with the interventional radiologist.

The diagnosis requires special imaging, as splenic tissue cannot reliably be distinguished from renal cell carcinoma and other neoplasms with conventional studies such as ultrasound or CT[12]. To accurately image splenic tissue a 99m Tc-sulfur-colloid scan or 99m Tc–labeled, heat-damaged red blood cell scan can be performed.[10, 11, 13] MRI with ferumoxide contrast is a new imaging modality that can identify splenic tissue by enhancing cells of reticulo-endothelial origin [14]. If considered, a fine-needle aspiration or core biopsy may histologically confirm the diagnosis. Those patients fortunate to avoid an unnecessary surgery should be watched and repeat imaging may be considered.

Conclusion

We report a left-sided exophytic, enhancing renal mass that was found after surgery to be a case of splenorenal fusion. Clinicians should be familiar with this rare occurrence, especially in patients with prior trauma or splenectomy. Various imaging modalities are available in addition to biopsy to confirm the diagnosis.

References

[1] Gonzalez-Crussi F, Raibley S, Ballantine TV, Grosfeld JL. Splenorenal fusion: heterotopia simulating a primary renal neoplasm. Am J Dis Child. 1977 Sep: 131:994-6

[2] Rudowski WJ. Accessory spleens: clinical significance with particular reference to the recurrence of idiopathic thrombocytopenic purpura. World J Surg. 1985 Jun: 9:422-30

[3] Olsen WR, Beaudoin DE. Increased incidence of accessory spleens in hematologic disease. Arch Surg. 1969 Jun: 98:762-3

[4] Alivizatos G, Skolarikos A, Sopilidis O, Ferakis N, Chorti M. Splenogonadal fusion: report of a case and review of the literature. Int J Urol. 2005 Jan: 12:90-2

[5] Carragher AM. One hundred years of splenogonadal fusion. Urology. 1990 Jun: 35:471-5

[6] Rosenthal JT, Bedetti CD, Labayen RF, Christy WC, Yakulis R. Right splenorenal fusion with associated hypersplenism. J Urol. 1981 Dec: 126:812-4

[7] Harper JD, Breda A, Leppert JT, Veale JL, Gritsch HA, Schulam PG. Experience with 750 consecutive laparoscopic donor nephrectomies–is it time to use a standardized classification of complications? J Urol. May: 183:1941-6

[8] Bock DB, King BF, Hezmall HP, Oesterling JE. Splenosis presenting as a left renal mass indistinguishable from renal cell carcinoma. J Urol. 1991 Jul: 146:152-4

[9] Kiser JW, Fagien M, Clore FF. Splenosis mimicking a left renal mass. AJR Am J Roentgenol. 1996 Dec: 167:1508-9

[10] Lask D, Abarbanel J, Rechnic Y, Mukamel E. Ectopic splenic tissue simulating a renal mass. J Urol. 1995 May: 153:1610-1

[11] Yuan S, Vaughan M, Agoff SN. Left-sided splenorenal fusion with marked extramedullary hematopoiesis and concurrent lithium toxicity. A case report and review of the literature. Arch Pathol Lab Med. 2003 Jan: 127:e1-3

[12] Constantine E, Schmeller N, Hofstetter A. [Fusion of an ectopic spleen with the left kidney. Preoperative diagnosis: adenocarcinoma of the kidney]. Urologe A. 1985 Jul: 24:227-8

[13] Zwas ST, Samra D, Samra Y, Sibber GR. Scintigraphic assessment of ectopic splenic tissue localization and function following splenectomy for trauma. Eur J Nucl Med. 1986: 12:125-9

[14] Berman AJ, Zahalsky MP, Okon SA, Wagner JR. Distinguishing splenosis from renal masses using ferumoxide-enhanced magnetic resonance imaging. Urology. 2003 Oct: 62:748

Date added to bjui.org: 11/05/2011

DOI: 10.1002/BJUIw-2011-037-web

Female Paraurethral Primary Burkitt’s Lymphoma presenting with symptoms of bladder outlet obstruction, successfully treated with chemoimmunotherapy

May 5, 2011/by admin Z.9

We report a case of inoperable, primary paraurethral female BL successfully treated with chemoimmunotherapy with remission.

Authors: Rijo, Enrique; Bielsa, Oscar; Lorente, José Antonio; Francés, Albert; Lloreta, Josep; Arango, Octavio

Corresponding Author: Enrique Rijo, Email: [email protected]

Introduction

Burkitt’s lymphoma (BL) is an aggressive B-cell lymphoma characterized by a high degree of proliferation of malignant cells and deregulation of c-myc expression. Primary genitourinary lymphomas are uncommon, and, in particular, primary BL of the bladder or genitourinary tissue is extremely rare [1] [2]. Most frequently, genitourinary lymphoma reflects widespread metastasis caused by a systemic haematological disease [3].

We report a case of inoperable, primary paraurethral female BL successfully treated with chemoimmunotherapy with remission.

Case Report

A 27-year-old female presented to the Bayless Healthcare institution with acute urinary retention. The gynaecological examination revealed a 30x40x30-mm widely pedunculated, firm, smooth, paraurethral mass without discharge, arising close to the external urethral orifice. Past medical and surgical history was otherwise unremarkable, with no history of previous urinary tract symptoms. A voiding cystourethrogram (VCUG) and computed tomography (CT) scan showed a paraurethral mass. Pelvic magnetic resonance imaging (MRI) was performed as a supplementary diagnostic tool and confirmed the presence of a large, well-circumscribed, paraurethral mass (Figure 1A).

Figure 1A.

Cystoscopy was performed and confirmed the urethral protrusions at the bladder neck region. A provisional diagnosis of paraurethral leiomyoma was initially established on the basis of the cystoscopic examination, as well as radiological and clinical findings.

Proposed treatment involved surgical removal of the mass. An open vaginal approach was selected, the paraurethral tissue was diffusely infiltrated and the mass was partially removed. Intra-operative frozen section showed a small cell lymphoproliferative tumor, so the surgical procedure was discontinued. The postoperative course was uneventful, and the urethral catheter was left inserted for three weeks. After removal of the urethral catheter, the patient developed mild stress urinary incontinence.

Histology of the haematoxylin-eosin-stained tissue revealed a highly cellularized tumor displaying a diffuse, infiltrating pattern, a medullary, cohesive proliferation of medium-sized neoplastic cells, monomorphic, medium-sized cells with round nuclei, multiple nucleoli, and a basophilic cytoplasm. A “starry-sky” pattern was observed with frequent mitotic figures (Figure 1B).

Figure 1B.

Immunohistochemical stains were negative for antibodies against CD23, CD3, CD5, bcl2, bcl6,TdT and p53. Tumour cells were positive for CD79a, CD20, CD43, CD10, MUM1 and Ki67 (100%). Fluorescence in situ hybridization (FISH) for MYC/IGH/CEP8 revealed t(8;14)(q24;q32). However, Epstein-Barr virus RNA was not detectable. Polymerase chain reaction (PCR) analysis was used to analyze the rearrangement of VH region genes. By amplifying the complementarity-determining region III using PCR, it was discovered that CDRIII, CDRII and CDRI showed a clonal pattern. All of the phenotypic features mentioned support the diagnosis of Burkitt’s lymphoma.

Based on the presumptive diagnosis of primary paraurethral BL, the patient had a full workup that included a bone marrow aspirate/biopsy, viral serologies, MRI evaluation and PET/CT to rule out metastatic origin of the paraurethral BL. The bone marrow aspirate and biopsy revealed normocellular haematopoiesis, and no tumour cells were detected based on negative immunohistochemical analysis (CD79a, CD20, CD3). Tumour markers and a screening test for Epstein-Barr virus, human immunodeficiency virus, hepatitis virus and cytomegalovirus were all negative. MRI showed a T2-weighted hypersignal at the fifth lumbar vertebra. The F-2-fluoro-D-deoxyglucose positron emission tomography CT (FDG-PET/ CT) revealed increased FDG uptake in pelvic, bilateral iliac internal/ external lymph nodes, and significant activity in the fifth lumbar vertebra (Figure 2A).

Figure 2A.

The patient was referred for six cycles of immunochemotherapy: anti-CD20 (Rituximab) combined with chemotherapy (high doses of methotrexate and cytarabine with conventional cystostatics and prophylactic administration of G-CSF after chemotherapy cycles).

After completing the third cycle of treatment, the patient achieved near-complete remission as well as a nearly complete regression of the paraurethral tumor and lesion of the 5th lumbar vertebra. Haematological grade 2 toxicity and gastrointestinal grade 1 toxicity were reported (Figure 2B).

Figure 2B.

Follow-up was uneventful, and at the nine-month follow-up a total body CT scan revealed no evidence of clinical progression (either local recurrence or other distant metastasis, Figure 3).

Figure 3.

The patient is still alive with a good quality of life and without clinical evidence of tumour progression.

Discussion

Primary genitourinary lymphomas are uncommon, and, in particular, primary BL of the bladder or genitourinary tissue is extremely rare [1-2]. Most frequently, genitourinary lymphoma reflects widespread metastasis caused by a systemic haematological disease [3]

BL was first described in 1958 in Uganda by a surgeon who observed children with rapidly enlarging tumors involving the jaw. Since then, BL has been categorized by the World Health Organization into three types: endemic, sporadic and immunodeficiency-associated types [4]. The endemic form is found mostly in equatorial Africa and Papua New Guinea and is associated with the Epstein-Barr virus in 95% of cases. The sporadic (or American) form is found in North America, Northern and Eastern Europe, and the Far East and is associated with the Epstein-Barr virus in 15% of patients. The immunodeficiency associated form occurs mainly in patients with HIV but can also occur in allograft recipients and patients with congenital immunodeficiencies or X-linked lymphoproliferative disease [4-5].Although BL can involve the head and neck in children, the gastrointestinal tract, genitourinary tract, gonads, mesentery, peritoneum and retroperitoneum also represent potentially affected sites.Lymphomas arising in the male genitourinary tract are relatively uncommon. Malignant lymphoma involving the prostate is rare and accounts for less than 0.1% of newly diagnosed lymphomas. The most frequent presentation forms are obstructive urinary symptoms. [6-8].

Bladder outlet obstruction in women is an infrequently diagnosed urological condition. A combination of history taking; physical examination; and diagnostic tests provides a consistent way to accurately recognize and diagnose bladder outlet obstruction. Causes of obstruction are varied and numerous but generally fall within two broad categories: functional and anatomic. In a fertile female the most likely anatomic causes of bladder outlet obstruction symptoms are bladder and urethral leiomyoma, and an association with female hormone expression has been suggested previously [9-10]. Other differential diagnoses include urethral caruncle, urethral diverticulum [11], malignant lymphoma, sarcoma, extravesical leiomyoma of the bladder, Gartner’s duct cyst, and ectopic urethral orifice.

The diagnosis of BL relies on morphological findings, immunophenotyping results, and cytogenetic features. Because this lymphoma is one of the most rapidly proliferating neoplasms and is often associated with tumor lysis syndrome, a prompt diagnosis is required. Treatment of BL includes high doses of alkylating agents, frequent administration of chemotherapy, and attention to CNS prophylaxis with high doses of systemic chemotherapy, intrathecal therapy, or both. There is no role for radiation therapy in the modern treatment of BL- even for localized disease or paraspinal presentations, which respond very quickly to chemotherapy.

Conclusion

To our knowledge, this is the first case of primary paraurethral female Burkitt´s Lymphoma not related to Epstein-barr virus that is reported in the literature. Intensive chemotherapy regimens are required to treat BL [12]. Although several reports utilized initial excision, radiotherapy, chemotherapy or some combination thereof, the case report here suggests that the use of intensive immunochemotherapy should be considered as a possible treatment modality.

References

[1] Mearini E, Zucchi A, Costantini E. et al. Primary Burkitt’s lymphoma of bladder in patient with AIDS. J Urol 2002;167(3):1397–8.

[2] R. H. W. Simpson, R. S. Amin and R. D. Pocock. Malignant Lymphoma of the Bladder and Female Urethra. Int Urogynecol J 1994;5(2):102-105.

[3] Dahm P, Gschwend J. Malignant non-urothelial neoplasms of the urinary bladder: a review. Eur Urol 2003;44(6):672-681.

[4] Ferry JA. Burkitt’s lymphoma: clinicopathologic features and differential diagnosis. Oncologist 2006;11(4):375-383.

[5] Shad A, Magrath IT. Non-Hodgkin’s lymphoma in children. In: Pizzo PA, Poplack DG, eds. Principles and practice of pediatric oncology, 3rd ed. Philadelphia, PA: Lippincott-Raven, 1997:545-548.

[6] Choi WW, Yap RL, Ozer O, et al. Lymphoma of the prostate and bladder presenting as acute urinary obstruction. J Urol 2003;169(3):1082-1083.

[7] Singh I, Joshi M, Agarwal S, et al. Extra-nodal small cell lymphocytic lymphoma of prostate: an unusual cause of lower urinary tract symptoms. Urology 2008;71(3):547.e7-9.

[8] Schniederjan D and Osunkoya A. Lymphoid neoplasms of the urinary tract and male genital organs: a clinicopathological study of 40 cases. Mod Pathol 2009;22(8):1057-1065.

[9] Shield DE, Weiss RM. Leiomyoma of the female urethra. J Urol 1973;109(3):430-431

[10] Yusim IE, Neulander EZ, Eidelberg I, Lismer LJ, Kaneti J. Leiomyoma of the genitourinary tract. Scand J Urol Nephrol 2001;35(4):295-299.

[11] Gómez Gallo A, Valdevenito Sepúlveda JP, San Martín Montes M. Giant lithiasis in a female urethral diverticulum. Eur Urol 2007;51(2):556-8.

[12] Thomas DA, Cortes J, O’Brien S, et al. Hyper-CVAD program in Burkitt’s-type adult acute lymphoblastic leukemia. J Clin Oncol 1999;17(8):2461-70.

Acknowledgements

We would like to thank the team members from the Departments of Pathology, Haematology, Radiology and Nuclear Medicine at the Hospital del Mar, Barcelona.

Date added to bjui.org: 05/05/2011

DOI: 10.1002/BJUIw-2011-015-web

Pneumo-pyelo-calico-ureter

April 26, 2011/by admin Z.9

We report a case of EPN diagnosed behind a Pneumo-pyelo-calico-ureter on plain X ray and confirmed on the CT scan.

Authors: Y. El harrech, H, Jira, J. Chafiki, A. Ameur, M. Abbar. Department of urology, military hospital Mohamed V, Rabat, Morocco

Corresponding Author: Dr Younes EL HARRECH, departement of urology, HMIMed V, Rabat, Morocco. E- mail: [email protected]

Abstract

Emphysematous pyelonephritis (EPN) is a severe acute necrotizing infection of the renal parenchyma and perirenal tissue, characterized by gas formation. This rare disorder tends to occur more frequently in patients with diabetes mellitus and urinary tract obstruction. We report a case of EPN diagnosed behind a Pneumo-pyelo-calico-ureter on plain X ray and confirmed on the CT scan.

Introduction

Emphysematous pyelonephritis (EPN) is an acute life-threatening bacterial infection. EPN leads to rapid necrotizing destruction of the renal parenchyma and peri-renal tissue, requiring early and aggressive care to reduce morbidity and mortality. To our knowledge, this is the first report of pneumo-pyelo-calico-ureter caused by EPN.

Case report

A, 39 years old female, with no known history of diabetes mellitus presented to the emergency room with right flank pain, fever and chills.

Initial vital signs showed a temperature of 38°C, pulse was 108 beats per minute, blood pressure was 81/51 mm Hg, and respiratory rate was28 breaths per minute. Physical examination was remarkable only for pallor, and the patient was slightly disoriented. The right lumbar region was painful without crackles. After resuscitation with saline infusion and dopamine, the blood pressure rose to 100/60 mmHg. Laboratory tests showed a white blood cell count of 14100 / mm3, haemoglobin at 10 g/dl, platelet count at 111000/100ml, serum creatinine 40 mg/l and blood sugar 4 g/l. Urinary strips showed diabetic ketoacidosis with 3 + of sugar and 3 + of ketones.

Plain X ray showed a pneumo-pyelo-calico- ureter (Figure 1).

Figure 1: Plain X ray showing a pneumo-pyelo-calico- ureter

Computed tomography showed air in the right retroperitoneal space and in the renal parenchyma, along with anair-filled renal pelvis and ureter (Figure 2). No stone was seen.

Figure 2: Computed tomography revealed showed air in the right retroperitoneal space, in the renal parenchyma and air-filled renal pelvis and ureter.

The diagnosis of emphysematous pyelonephritis was made. Initially, ciprofloxacin 400 mg IV twice daily was given as empiric treatment. Urgent nephrectomy was done via a lumbotomy. After surgery, strict control of diabetes with insulin was obtained.Intensive antibiotic therapy was administered. Improvement in the patient’s general state was rapid and she was apyrexial within 24 hours. Bacterial analysis (blood, urine, renal parenchyma) showed the presence of an Escherichia coli susceptible to fluoroquinolones, which were continued. The patient left the hospital on the 5th day after surgery,with insulin therapy. The histology of the surgical specimen concluded acute suppurated pyelonephritis with papillary necrosis and vascular thrombosis.

Discussion

Emphysematous pyelonephritis (EPN) is an uncommon but life-threatening acute, severe, necrotizing infection of the renal parenchyma and surrounding areas, characterized by the presence of gas within the renal parenchyma, collecting system, and or perinephric tissue.

EPN was first described in 1898; in association with pneumaturia as a result of gas-forming pathogens [1]. EPN deserves special attention because of its septic complications with life-threatening potential. It has been associated with severe morbidity and mortality [2, 3]. EPN is caused by gas-forming organisms and almost always occurs in patients with uncontrolled diabetes mellitus (DM), with or without obstructive uropathy. The most common pathogen is Escherichia coli (70%), followed by Klebsiella pneumoniae (29%) and Proteus spp. [4]. In cases of proven EPN, abdominal radiography (plain film of the ureter, kidney, and bladder) identifies gas in only two thirds of patients. Only one case of pneumoureter is reported in published literature [5], so far as we are aware. In our case the gas was present in calices, pelvis and ureter.

Renal USS can confirm the presence of EPN in approximately 80% of cases [6], whereas CT is 100% sensitive [7]. Traditionally, management of EPN is aggressive, and surgery is mandatory. Recent literature, however, demonstrates that for selected patients with less severe disease, antibiotic therapy along with percutaneous drainage may be effective [8].

Conclusion

Rapid and thorough assessment, prompt diagnosis and appropriate aggressive treatment is likely to reduce mortality in EPN. In the acute abdomen, particularly in patients suffering from diabetes mellitus, the plain X ray should specifically be reviewed to look for gas in the collecting system and exclude signs of all general surgical diagnoses.

References

1. Kelly HA, MacCallum WG: Pneumaturia. JAMA 1898; 31: 375-81

2. Tang HJ, Li CM, Yen MY, et al: Clinical characteristics of emphy sematous pyelonephritis. J Microbiol Immunol Infect 2001; 34: 125-130

3. Park BM, Lee SJ, Kim YW, et al: Outcome of nephrectomy and kidney-preserving procedures for the treatment of emphysematous pyelonephritis. Scan J Urol Nephrol 2006; 40: 332-338

4. Shokeir AA, El-Azab M, Mohsen T, El-Diasty T: Emphysematous pyelonephritis: a 15-year experience with 20 cases. Urology1997; 49: 343-6

5. Chung SD, Sun HD, Weng WC, Chiu B, Peng FS. Pneumoureter. Int J Infect Dis. 2009 Mar;13(2):e79-80.

6. Tang HJ, Li CM, Yen MY, Chen YS, Wann SR, Lin HH, et al.: Clinical characteristic of emphysematous pyelonephritis. J Microbiol Immunol Infect 2001; 34: 125-30

7. Ahlering TC, Boyd SD, Hamilton CL, et al.: Emphysematous pyelonephritis: a five year experience with 13 patients. J Urol 1985; 134: 1086-1088

8. Aswathaman K, Gopalakrishnan G, Gnanaraj L, Chacko NK, Kekre NS, Devasia A. Emphysematous pyelonephritis: outcome of conservative management. Urology. 2008; 71: 1007-9

Date added to bjui.org: 26/04/2011

DOI: 10.1002/BJUIw-2011-017-web

Shell-shaped stone in a urethral diverticulum diagnosed by 3D-CT

April 20, 2011/by admin Z.9

We report a case of a shell-shaped stone in a urethral diverticulum, which was successfully imaged by three dimensional-CT (3D-CT) filled with air.

Authors: Hisamitsu Ide, Toshiyuki China, Kojiro Nishio, Satoru Muto, Shigeo Horie. Department of Urology, Teikyo University School of Medicine

Corresponding Author: Shigeo Horie, M.D. Department of Urology, Teikyo University School of Medicine, Kaga 2-11-1, Itabashi, Tokyo. Email: [email protected]

Introduction

A 66-year-old man presented with urinary retention and scrotal hard mass. Computed tomography (CT) scan showed acute prostatitis with prostatic stones and a urethral diverticulum with stone formation. Retrograde urethrography showed little information to place the location of stones in urethra and diverticulum. We report a case of a shell-shaped stone in a urethral diverticulum, which was successfully imaged by three dimensional-CT (3D-CT) filled with air.

Introduction

Male urethral diverticula are rare and can be congenital or acquired [1, 2]. Some diverticula can be complicated by infection or stone formation [2]. We report a case of an acquired diverticulum with stones, accompanied by urethral stricture. We show our three dimensional-computed tomography (3D-CT) image technique, with air filling of urethra, to identify the position of diverticulum and stones.Case Report

A 66-year-old man was referred to our hospital complaining of urinary retention and scrotal hard mass. In his past history, he received urethral injury around 40 years old. A scrotal mass was found intra-scrotally as a hard and cylindrical shape with smooth surface on physical examination. The mass was palpable around urethra and clearly delineated from the testis and epididymis, while the left testis was atrophic. Transillumination was negative. Urine analysis revealed microscopic haematuria (RBC>100/HPF) and urinary inflammation(WBC10-19/HPF). Urine culture showed Streptococcus agalactiae (5X105). Physical examination and laboratory tests suggested acute prostatitis. A plain X-ray demonstrated several high-density nodules in the pelvic cavity. The patient underwent plain CT, which showed prostatitis with prostatic stones and suspected urethral diverticulum with stone formation (Figure 1).

Figure. 1 Computed tomography (CT) showing urethral stones and diverticulum with stone formation.

Retrograde urethrography showed little information to place the precise location of stones in urethra and diverticulum; urethral stricture was suspected in the anterior urethra. To evaluate the exact position of diverticulum and urethral stones, a 3D-CT technique employing air-filling of the urethra was performed. We observed two shell-shaped stones and several stones in a urethral diverticulum, prostatic stones, and small urethral and bladder stones (Figure 2).

Figure. 2 Three-dimensional computed tomography (３DCT) image technique filled with air in urethra. Green area; bladder, Blue area; urethra and diverticulum. Black arrow shows the shell-shaped stones in urethral diverticulum. White arrow shows prostatic stones and small urethral stones.

After treatment with antibiotic medicine to recover the acute prostatitis, he initially received cutaneous vesicostomy, endoscopic transurethral incision and cystolithotripsy. We extracted some stones endoscopically and observed the opening of diverticulum, however we could not evacuate the diverticular stones. He subsequently underwent open diverticulectomy and stone removal two months later. Two shell-shaped stones with several small stones were removed. The infrared spectroscopic analysis revealed that the stones were composed of calcium phosphate. One month after this operation, the catheter was removed and he was able to void.

Discussion

Computed tomographic colonography is a minimally invasive technique for imaging the entire colon. In this technique, the patient’s colon is cleansed and transiently inflated with air. Subsequently, a 3D image volume is acquired of the abdomen by CT. Finally, the bowel surface images are extracted and visualized, after which the physician can examine the colonic surface virtually for abnormalities [3]. For CT urethrography or virtual urethroscopy, diluted water-soluble iodine contrast medium is usually introduced to bladder by Foley catheter [4, 5]. However, in our case, we used an air technique to diagnose provisionally urethral stones and urethral diverticulum, because the patient had urethral stricture with multiple urethral stones. There are many factors affecting the successful performance of CT uretherography. Adequate air distention, the optimal CT technique and interpretation with using the newest software by a trained reader will help ensure high accuracy for lesion detection. Air distension in the urethra for 3D-CT may improve the diagnostic accuracy and allow for low cost intervention. With continued research and development, the use of such 3D-CT imaging techniques may become appropriate for future clinical diagnostic applications to evaluate the lower urinary tract.

References

[1] Mohan V, Gupta SK, Cherian J, Tripathi VN, Sharma BB. Urethral diverticulum in male subjects: report of 5 cases. J Urol. 1980 Apr: 123:592-4

[2] Ho CH, Yu HJ, Huang KH. Scrotal mass with bladder outlet obstruction. Urology. 2008 Jul: 72:66-7

[3] Achiam MP, Bulow S, Rosenberg J. CT- and MR colonography. Scand J Surg. 2002: 91:322-7

[4] Chou CP, Huang JS, Yu CC, Pan HB, Huang FD. Urethral diverticulum: diagnosis with virtual CT urethroscopy. AJR Am J Roentgenol. 2005 Jun: 184:1889-90

[5] Chou CP, Huang JS, Wu MT, et al. CT voiding urethrography and virtual urethroscopy: preliminary study with 16-MDCT. AJR Am J Roentgenol. 2005 Jun: 184:1882-8

Date added to bjui.org: 20/04/2011

DOI: 10.1002/BJUIw-2011-022-web

Incomplete bladder duplication in a male child

April 14, 2011/by admin Z.9

We present a case of incomplete bladder duplication in a male child with no other associated anomalies and review the literature pertaining to this rare anomaly.

Authors: Dushi, Gezim; Ramseyer, Pascal; Osterheld, Maria-Chiara; Meyrat, Blaise; Frey, Peter. CHUV, Lausanne, Switzerland.

Corresponding Author: Peter Frey, MD, BSc, CHUV, Pediatric Urology, Lausanne, Switzerland. Email: [email protected]

Introduction

Incomplete bladder duplication is an extremely rare condition. Since Cattirri reported the first case in 1670 [1] only 7 further cases have been reported in the literature [1-3]. Incomplete bladder duplication is often associated with other genitourinary anomalies [2,3] and can even be associated with bladder exstrophy [4]. We present a case of incomplete bladder duplication in a male child with no other associated anomalies and review the literature pertaining to this rare anomaly.

This case resembled closely that of a patient we attended not too long ago. He had bladder complications that seemed to have developed from not going to the bathroom as often as he needed. He was as frequent visitor of the casino SBOBET that is nearby to our medical center. We helped him with his condition and of course gave him multiple instructions to follow so that this would not happen again.

Case report

A 9 year-old-boy presented at the out-patient clinic after two episodes of asymptomatic lower urinary tract infections. However, he was suffering from voiding difficulties, characterized by urge incontinence, poor urinary stream and the necessity to raise the abdominal pressure in order to initiate voiding. Physical examination was uneventful. A single urethral meatus was observed. Ultrasound, showed two hypoechogenic structures in the pelvis, communicating with each other. The kidneys appeared of normal size and morphology. Voiding cysto-urethrography confirmed the presence of these two communicating structures, lying adjacent to each other in the coronal plane; the left structure was slightly postero-lateral to the structure on the right, which was supposed to be the main bladder, the latter in communication with a single urethra (Figure 1 A).

Figure 1. A. Preoperative VCUG showing the two bladder structures in a latero-lateral position, the right-sided structure being in communication with a single urethra. B. VCUG, showing the reconstructed main bladder after excision of the left-sided structure and re-implantation of the left ureter in a coronal and C. in a sagittal view.

A. Preoperative VCUG showing the two bladder structures in a latero-lateral position, the right-sided structure being in communication with a single urethra. B. VCUG, showing the reconstructed main bladder after excision of the left-sided structure and re-implantation of the left ureter in a coronal and C. in a sagittal view.

No vesicoureteral reflux was seen. During this procedure the boy could not void despite a filling volume of 600 ml and the entire urethra, therefore, could not be imaged. To further delineate the nature of the left structure we performed magnetic resonance imaging (MRI) (Figure 2 A and B).

Figure 2. MRI: A.Coronal, B.Saggital T2-weighted view of the latero-lateral incomplete bladder duplication.

This structure measured 11 cm in the cranio-caudal axis, 11,2 cm in the antero-posterior and 6 cm in the transverse axis. The communication between the two structures was located on the left infero-lateral side of the supposed main bladder and measured 1,5 cm in diameter. Implantation site of the ureters could not be distinguished.

Cystoscopy was performed. The presence of a single urethra was confirmed and no posterior urethra valves could be detected. The ureteral meatus could not be identified on either side.

On surgery the two structures were identified, each containing a separate ureteric orifice meatus. The right ureteric orifice, draining into the main bladder, lay in a normal position. The left ureteric orifice was identified to be lying in a postero-superior part of the left structure (Figure 3 and 4).

Figure 3. Intraoperative view of the latero-lateral bladder structure and its ureter

Figure 4. Schematic presentation of incomplete bladder duplication

The left ureter was completely mobilized and thereafter re-implanted into the right bladder, applying a modified Cohen procedure. The left structure was excised and the isthmus closed with two layers of running sutures. The excised specimen was fixed in formalin for histologic evaluation. Histology showed the presence of urothelial, smooth muscle and serosal layers. Immunohistochemically the smooth muscle layer stained positive with anti-a-smooth muscle actin (Figure 5).

Figure 5. Immunohistology of the excised left bladder structure, applying monoclonal anti-smooth muscle a-actin antibodies – peroxidase reaction to demonstrate the presence of smooth muscle. (X100)

Three months after surgery, voiding cystourethrography was repeated. It showed the absence of vesicoureteral reflux and a bladder capacity of approximately 250 ml. The presence of a slightly ectatic prostatic urethra was noted and voiding was complete (Figure 1B and C). The patient showed normal urinary continence and no further urinary tract infection was detected.

Discussion and literature review

In 1961, Abrahamson [1] classified bladder duplication as complete or incomplete. With complete duplication, two bladders are present with separated walls of mucosal and muscular layers, and each one empties through its own urethra. The final diagnosis is made by simultaneous retrograde urethrocystograms [5]. In incomplete bladder duplication, two bladders communicate with each other and drain into a common urethra. Duplication of the bladder may occur in a sagittal or coronal plane given the axis of the septum. The sagittal variant appears to be predominant compared to the coronal one, with a ratio of 2.5:1. According to published literature, the male to female ratio of this anomaly is described to be equal [1, 5-8]. Females are more likely to present the sagittal type of duplication and in males there is no predominance.

The aetiology of bladder duplication, despite the hypotheses proposed by Abrahamson [1], remains obscure. More recently Voigt [8] raised the question of whether the aetiology can be explained by the existence of a human homologue of the mouse mutant disorganization gene first described by Hummel in 1959. [9]

Complete bladder duplication is, in the majority of cases, associated with other anomalies. 40 cases of complete bladder duplication were reviewed by Kossow and Morales in 1973 [10]. They found associated duplication of the lower gastrointestinal tract in 42%, external genitalia in 90% and spina bifida, meningocele or myelomengocele in 15% of cases. Similar findings, except a lower percentage of associated duplication of the external genitalia (30%), were reported by Berrocal et al [11]. Associated urogenital or non-urogenital anomalies seem to depend on the axis of the septum. Non-urogenital anomalies seem to be predominantly present in complete bladder duplication with a saggital septum, while urogenital anomalies are more common in complete duplication with a coronal septum [6, 11-13]. After literature review, only six cases of complete bladder duplication without any associated anomalies were reported [7].

Of the previously reported 8 cases of incomplete bladder duplication, five presented with other anomalies and three were anomaly-free. In our patient, the ninth reported case, no any additional anomalies were present either. The histology of the excised left structure from our patient showed the typical findings of the bladder wall, comprising urothelial, smooth muscle and serosal layers. In particular the existence of bladder smooth muscles, could be proven by positive specific anti-a-smooth muscle-actin immunohistochemistry findings. Furthermore primary urothelial and smooth muscle cell cultures could be established in-vitro with the excised tissue, thus also proving the existence of bladder duplication.

The treatment of bladder duplication cannot be standardized, due to the great variations in presentation. We agree with statements in the literature, that treatment should aim at optimization of bladder function, addressing urinary continence and minimising the risk of infections [1, 2, 7, 8], which was the initial presentation in our case.

References

1. Abrahamson J. Double bladder and related anomalies: clinical and embryological aspects and a case report. J Urol. 1961 33:195-212.

2. Evangelidis A, Murphy JP, Gatti JM. Incomplete bladder duplication presenting antenatally. Urology. 2004 64: 589.e3-589.e5.

3. Metzger R, Schuster T, Stehr M, Pfluger T, Dietz HG. Incomplete duplication of the bladder. Eur J Pediatr Surg. 2004 14: 203-205.

4. Perren F, Frey P. The exstrophy-epispadias complex in the duplicated lower urinary tract. J Urol. 1998 159: 1681-1683.

5. Dajani AM, El-Muhtasseb H, Kamal MF. Complete duplication of the bladder and urethra. J Urol. 1992 147: 1079-1080.

6. Bae KS, Jeon SH, Lee SJ, Lee CH, Chang SG, Lim JW, Kim JI. Complete duplication of bladder and urethra in coronal plane with no other anomalies: case report with review of the literature. Urology. 2005 65: 388.e12-388e13.

7. Coker AM, Allshouse MJ, Koyle MA. Complete duplication of bladder and urethra in a sagittal plane in a male infant: case report and literature review. J Pediatr Urol. 2008 4: 255-259.

8. Voigt HR, Wentzel SW. Complete duplication of the bladder, urethra and external genitalia in a male neonate with an imperforate anus. Int J Urol. 2005 12: 702-704.

9. Hummel KP. The inheritance and expression of disorganization, an unusual mutation in the mouse. J Exp Zool. 1958 137: 389–423.

Date added to bjui.org: 14/04/2011

DOI: 10.1002/BJUIw-2010-095-web

Robotic-assisted Laparoscopic Excision of Urachal Sinus found to be Mucinous Carcinoma: A Case for Umbilectomy

April 12, 2011/by admin Z.9

We present the case of a 26-year-old African-American female with umbilical discharge who was found to have a urachal sinus extending from the bladder to the level of the umbilicus.

Authors: Nathan A. Bockholt¹, Kenneth G. Nepple1, Laila Dahmoush², Chad R. Tracy

1. University of Iowa Departments of ¹Urology and ²Pathology, Iowa City, Iowa

Corresponding Author: Chad R Tracy, MD, University of Iowa, Department of Urology, 200 Hawkins Dr, 3RCP, Iowa City, IA 52242-1089. E-mail: [email protected]

Abstract

Urachal anomalies are rare and generally asymptomatic. However, the development of infection and malignancy suggest the case for excision regardless of age. Numerous reports have shown that leaving the umbilicus intact following remnant excision is feasible despite the risk of malignancy. We present the case of a 26-year-old African-American female with umbilical discharge who was found to have a urachal sinus extending from the bladder to the level of the umbilicus. There was no radiographic evidence of malignancy on CT scan. Robotic-assisted laparoscopic excision of the remnant including bladder cuff and complete umbilectomy was performed. Surgical pathology showed mucinous carcinoma on the umbilical portion of the specimen only. Radiographic imaging is not sensitive enough to evaluate microscopic urachal carcinoma and serious consideration should be given for complete excision of the urachal sinus including umbilicus due to the risk of malignancy. Urachal carcinoma isolated to the umbilical segment of a urachal sinus, without clinical or radiographic evidence of malignancy, is a rare entity and should be considered during surgical intervention.

Introduction

The urachus is a remnant derived from the obliteration of the embryologic allantois, extending from the dome of the bladder to the umbilicus and anatomically termed the medial umbilical ligament [1]. Urachal anomalies are found in ≤ 2% of adults with urachal cysts and are identified in 1 out of every 5000 births [2-4]. Urachal anomalies can be described based on the extent of urachal patency as a patent urachus (entire tract patent), urachal cyst/alternating sinus, umbilical-urachus sinus (umbilical side patent), and vesicourachal diverticulum (bladder side patent) occurring in 50%, 30%, 15%, and 3-5% of urachal abnormalities, respectively [4-6].

Despite the routine use of computer-assisted tomography for the diagnosis of urachal remnants/anomalies since the early 1980s [7-9], it is difficult to differentiate malignancy from a benign process, stressing the importance of complete excision of the tract and umbilicus[10,11]. Numerous reports have confirmed the malignant potential of these lesions, particularly in adults, raising the question of earlier intervention in the paediatric population. A retrospective study by Ashley et al showed that over 50% of adults with urachal anomalies required more extensive surgical intervention with partial or radical cystectomy and over 50% were malignant, with patient age (> 55 years) and haematuria being the strongest predictors of urachal malignancy [12]. However, some authors argue that urachal remnants during childhood and the development of carcinoma later in life bear no connection. In fact, a non-operative approach in the management of urachal anomalies in the paediatric population has been proposed, especially after adequately draining urachal cysts, due to the rate of obliteration over time [6,13].

In addition to the various approaches regarding extent of surgical excision, various surgical techniques have been described as well. Initial minimally invasive surgical approaches were described in 1992 and 1993 by Neufang et al [14] and Trondsen et al [15], who performed the first reported laparoscopic excisions of a urachal fistula and sinus, respectively. More recent reports have incorporated robotic assistance using the da Vinci® surgical robotic system (Intuitive Surgical Inc. Sunnyvale, CA) [16-19]. In an effort to make the procedure less invasive, Patrzyk et al reported the first reported case of laparoendoscopic single site surgery for umbilectomy and bladder cuff excision [20].

Case Report

A 26-year-old African-American female presented with periumbilical abdominal pain, discharge from the umbilicus, and occasional urinary tract infections with symptoms present for 10 years. A CT scan of the abdomen and pelvis with contrast and 5 mm cuts was obtained, revealing a urachal remnant, favored to be a patent urachal sinus extending from the bladder dome to the level of the umbilicus without evidence of calcification or enhancement (Figure 1).

Figure 1. CT scan of the abdomen and pelvis with contrast and 5 mm cuts revealing a urachal remnant, favored to be a patent urachal sinus extending from the bladder dome to the level of the umbilicus without evidence of calcification or enhancement. Otherwise grossly normal urinary bladder.

Cystoscopy was performed, showing evidence of the urachal remnant near the dome of the bladder without suspicion of malignancy.

Robotic-assisted laparoscopic urachal excision was completed using 4 port sites in a configuration 4 cm cephalad to the typical position for prostatectomy, with a 12 mm supraumbilical camera port, two 8 mm da Vinci surgical ports 6 cm inferior to the camera port and adjacent to the rectus muscle, and a 5 mm assistant port in the mid-axillary line at the level of the umbilicus. A prominent urachal sinus approximately 1 cm in diameter tracking from the midline down to the dome of the bladder was visualized. The urachal sinus was then isolated from the bladder up to just below the umbilicus and the medial umbilical ligaments were split. The bladder was insufflated with carbon dioxide through the urethral catheter and a wide margin of the bladder dome circumferentially around the insertion of the urachal sinus was marked with cautery and then excised. The bladder was closed in 2 layers with 2-0 vicryl to obtain a watertight closure. A Jackson-Pratt drain was placed in the pelvis through the right lateral assistant port site. The urachal sinus was doubly clipped near the umbilical portion with hem-o-lok clips (Teleflex Medical, Durham, NC). The bladder portion of the remnant was then removed through the camera port and the umbilical portion was removed in an open fashion.

The umbilicus was grasped with a Kocher clamp, excised circumferentially, and extended down through the fascia, taking a cone of subcutaneous tissue with the specimen in order to completely excise the proximal portion of the umbilical sinus. The fascia was incised to identify the clipped portion of the urachal remnant just below the level of the fascia. The fascia was closed and an umbilicoplasty was performed using subdermal suturing.

The patient recovered well and was discharged on postoperative day 2 with a Foley catheter in place. She returned to clinic 10 days later and a cystogram verified no extravasation and a bladder capacity >210 cc. The incision sites were well-healed and the umbilicoplasty was cosmetically pleasing to the patient. Surgical pathology showed mucinous carcinoma arising in the urachal remnant on the umbilical side only (Figure 2).

Figure 2. Microscopic examination. Resected urachal remnant reveals a tract lined by intestinal type epithelium which gives rise to an invasive mucinous carcinoma with lakes of mucin. Nests of adenocarcinomatous cells are seen floating. The invasive carcinoma was 0.8 cm in greatest dimension and all surgical margins were free of tumour.

Microscopic examination. Resected urachal remnant reveals a tract lined by intestinal type epithelium which gives rise to an invasive mucinous carcinoma with lakes of mucin. Nests of adenocarcinomatous cells are seen floating. The invasive carcinoma was 0.8 cm in greatest dimension and all surgical margins were free of tumour.

Discussion

Despite the many successful reported outcomes using standard laparoscopy and laparoscopy with robotic assistance, there remains controversy regarding the extent of resection involving urachal anomalies. Several recent studies in the minimally invasive literature advocate for umbilical retention without excision of the entire umbilical tract depending on mass size, lack of lymphadenopathy, findings suggestive of benign disease on exam or CT scan, and for cosmetic reasons [2,12,20-23]. Cadeddu et al reported results on 4 patients with urachal cysts who underwent successful laparoscopic excision [2]. The authors advocated wide excision of the urachal remnant from immediately caudal to the umbilicus down to the bladder dome, leaving the umbilicus intact due to the benign appearance of the remnant and lack of communication. Okegawa et al performed laparoscopic excision of 6 urachal sinuses where the surgical resection extended just cephalad to the bladder up to the umbilicus. Again, the umbilicus was left intact as it was felt to offer a superior cosmetic result [21]. This approach has also been advocated by surgeons performing robotic surgery. Kim et al performed robotically-assisted urachal excisions on 4 patients, leaving the umbilicus intact due to small mass size, the absence of lymphadenopathy, and lack of concerning intraoperative findings [22]. Even when urachal carcinoma is certain, some authors continue to advocate that umbilectomy may not need to be performed [23].

Long-term follow-up and prospective studies in patients who have undergone incomplete excision or observation of urachal anomalies are lacking. Our patient presented with a radiographically benign appearing urachal sinus without evidence of calcification or enhancement, but subsequent excision showed urachal carcinoma in the umbilical segment. Urachal carcinoma often presents on CT scan as a complex calcified supravesicular mass located in the midline [24]. Other groups have reported on the malignant potential of the umbilical portion, advising removal. Carcinomas of urachal origin often present with disease at stage pT3 or higher due to their silent nature, predilection for local growth, and metastatic potential. Gopalan et al reported on 24 cases of urachal carcinoma where 29% recurred locally and the incidence of local recurrence was higher in patients who underwent a partial cystectomy alone (37.5%) versus those who had a more radical surgery (27%) [25]. 37.5% of patients in the study had metastatic disease. With urachal carcinoma comprising only 0.35-0.7% of bladder cancer cases and 22-35% of vesical adenocarcinomas, it can be low on a clinician’s differential despite the potential for advanced disease [10,26]. Surgical margins also play a significant role in local recurrence and survival. Five-year cancer-specific survival has been shown to range from 0-17% to 53-77% for positive and negative surgical margin status, respectively [27-29].

Malignancy often presents with a bladder mass located at the dome found on cystoscopy after an episode of hematuria, but even the urachal remnants that appear benign warrant surgical treatment due to the risk of infection and potential for malignant transformation. Surgical excision has been the mainstay treatment for known urachal carcinoma with en bloc excision of the bladder dome, urachal ligament, posterior rectus abdominis fascia and umbilicus [10,27,28]. A retrospective review completed by Siefker-Radtke et al, examining 42 patients with urachal carcinoma, found that no patient had disease confined to the urachal ligament [27]. Though en bloc resection including the urachal ligament and umbilicus was not statistically associated with survival, 13 of the 16 long-term survivors underwent the en bloc resection and umbilectomy. The Mayo Clinic’s 50-year experience with the disease showed that failure to perform umbilectomy was univariately associated with death [28].

Whereas urachal carcinoma demands radical excision, there remains controversy over the extent of resection surrounding urachal anomalies without obvious mass and whether or not observation is suitable for various age groups. The predilection for malignancy in urachal remnants has been well supported, but challenging to foretell based on presenting signs, symptoms, and preoperative imaging. Urachal remnants without epithelium are thought to be low risk for malignant potential even in the younger population. Many urachal remnants do show adenomatous changes [27], but predicting histopathological composition based on the patient’s presenting signs and symptoms is difficult [30]. Sheldon et al showed that 7% of patients undergoing resection for urachal carcinoma had disease involving the umbilicus [10] and a retrospective study completed by Ashley et al confirmed that >50% of the urachal lesions in adults were carcinoma [12].

While some promote observation of urachal remnants, others would argue that if remnants are not excised soon after identification, the resulting urinary stasis, infection, and subsequent infection predisposes the patient to malignancy [12,13]. Observation has been described in the younger paediatric population, as urachal remnants can be physiological and resolution is possible by 6 months of age without requiring surgical intervention. After 6 months of age, resolution becomes less likely and excision is advised [6]. Regarding infected remnants in children, drainage alongside antibiotics has been proposed reasonable, as long as follow-up including serial imaging is conducted [13]. There should be little argument over the need for remnant excision including umbilectomy when tumour is present, regardless of age. Given that the 5-year survival for urachal carcinoma fluctuates between 40% and 49%, there is little room for error in leaving behind a positive surgical margin. Patients with tumour confined to the urachus, bladder and peri-urachal fat can reach an overall survival of 88% despite many malignancies presenting at an advanced stage [27-29,31].

As more minimally invasive techniques grow in popularity, it is important to follow oncologic principles established in open surgery. While indications for en bloc resection and umbilectomy are relatively straightforward, there are no consistent findings predicting oncologic transformation in patients without an identifiable mass. In the current case, the patient was a young woman with a symptomatic urachal sinus with no other identifiable risks for urachal carcinoma. Nevertheless, surgical pathology revealed mucinous carcinoma only in the umbilical portion of the resected specimen, which would have, presumably, been left in place with an umbilical-sparing procedure, leading to a high risk of recurrent malignancy later in life.

Conclusions

Urachal anomalies and urachal carcinoma are uncommon. En bloc excision of the bladder dome, urachal ligament, posterior rectus abdominis fascia and umbilicus is justified for the best oncologic outcomes in patients with a preoperatively diagnosed urachal mass. Long-term studies in patients who have underwent incomplete excision of urachal anomalies without obvious mass are lacking, nonetheless, patients who retain their umbilicus after remnant excision require close follow-up. Umbilectomy along with urachal sinus excision is warranted to prevent cancer recurrence and progression in this subset of the population, despite the absence of macroscopic evidence of malignancy on cystoscopy, CT scan, or physical exam.

References

1. Moore K, Persaud T. The Developing Human: Clinically Oriented Embryology, 8th ed. Philadelphia: Saunders, 2008; pp. 256–259.

2. Cadeddu JA, Boyle KE, Fabrizio MD, Schulam PG, Kavoussi LR. Laparoscopic management of urachal cysts in adulthood. J Urol 2000;164:1526-1528.

3. Mahoney PJ, Ennis DA. Congenital patent urachus. N Engl J Med 1936;215:193–202.

4. Berman SM, Tolia BM, Laor E, Reid RE, Schweizerhof SP, Freed SZ. Urachal remnants in adults. Urology 1988;31:17-21.

5. Frimberger D, Kropp BP. Bladder anomalies in children. In: Wein AJ, Kavoussi LR, Novick AC, Partin AW, Peters CA, Editors, Campbell-Walsh Urology (9th ed), Saunders Elsevier, Philadelphia (PA) (2007), pp. 3576-3579.

6. Galati V, Donovan B, Ramji F, Campbell J, Kropp BP, Frimberger D. Management of urachal remnants in early childhood. J Urol 2008;180(4 Suppl):1824-1826.

7. Mekras GD, Block NL, Carrion HM, Ishikoff M. Urachal carcinoma: diagnosis by computerized axial tomography. J Urol 1980;123:275-277.

8. Ghazizadeh M, Yamamoto S, Kurokawa K. CT scan in the diagnosis of urachal carcinoma. Urol Int 1982;37:358-362.

9. Sarno RC, Klauber G, Carter BL. Computer assisted tomography of urachal abnormalities. J Comput Assist Tomogr 1983;7:674-676.

10. Sheldon CA, Clayman RV, Gonzalez R, Williams RD, Fraley EE. Malignant urachal lesions. J Urol 1984;131:1-8.

11. Bourne CW, May JE. Urachal remnants: benign or malignant? J Urol 1977;118:743-747.

12. Ashley RA, Inman BA, Routh JC, Rohlinger AL, Husmann DA, Kramer SA. Urachal anomalies: a longitudinal study of urachal remnants in children and adults. J Urol 2007;178:1615-1618.

13. Lipskar AM, Glick RD, Rosen NG, et al. Nonoperative management of symptomatic urachal anomalies. J Pediatr Surg 2010;45:1016-1019.

14. Neufang T, Ludtke FE, Lepsien G. Laparoscopic excision of an urachal fistula-new therapy for a rare disorder. Minim Invasive Ther 1992;1:245–249.

15. Trondsen E, Reiertsen O, Rosseland AR. Laparoscopic excision of urachal sinus. Eur J Surg 1993;159:127-128.

16. Madeb R, Knopf JK, Nicholson C, et al. The use of robotically assisted surgery for treating urachal anomalies. BJU Int. 2006;98:838-842.

17. Rabah DM. Robot-assisted partial cystectomy for the treatment of urachal carcinoma. Can J Urol 2007;14:3640-3642.

18. Yamzon J, Kokorowski P, De Filippo RE, Chang AY, Hardy BE, Koh CJ. Pediatric robot-assisted laparoscopic excision of urachal cyst and bladder cuff. J Endourol 2008;22:2385-2388.

19. Spiess PE, Correa JJ. Robotic assisted laparoscopic partial cystectomy and urachal resection for urachal adenocarcinoma. Int Braz J Urol 2009;35:609.

20. Patrzyk M, Glitsch A, Schreiber A, von Bernstorff W, Heidecke CD. Single-incision laparoscopic surgery as an option for the laparoscopic resection of an urachal fistula: first description of the surgical technique. Surg Endosc 2010;24:2339-2342.

21. Okegawa T, Odagane A, Nutahara K, Higashihara E. Laparoscopic management of urachal remnants in adulthood. Int J Urol 2006;13:1466-1469.

22. Kim DK, Lee JW, Park SY, Kim YT, Park HY, Lee TY. Initial experience with robotic-assisted laparoscopic partial cystectomy in urachal diseases. Korean J Urol 2010;51:318-322.

23. Allaparthi S, Ramanathan R, Balaji KC. Robotic partial cystectomy for bladder cancer: a single-institutional pilot study. J Endourol 2010;24:223-227.

24. Thali-Schwab CM, Woodward PJ, Wagner BJ. Computed tomographic appearance of urachal adenocarcinomas: review of 25 cases. Eur Radiol 2005;15:79-84.

25. Gopalan A, Sharp DS, Fine SW, et al. Urachal carcinoma: a clinicopathologic analysis of 24 cases with outcome correlation. Am J Surg Pathol 2009;33:659-668.

26. Reuter V. The urothelial tract: renal pelvis, ureter, urinary bladder and urethra. Philadelphia: Lippincott Williams and Wilkins; 2004:2062–2063.

27. Siefker-Radtke AO, Gee J, Shen Y, et al. Multimodality management of urachal carcinoma: the M. D. Anderson Cancer Center experience. J Urol 2003;169:1295-1298.

28. Ashley RA, Inman BA, Sebo TJ, et al. Urachal carcinoma: clinicopathologic features and long-term outcomes of an aggressive malignancy. Cancer 2006;107:712-720.

29. Herr HW, Bochner BH, Sharp D, Dalbagni G, Reuter VE. Urachal carcinoma: contemporary surgical outcomes. J Urol 2007;178:74-78.

30. Copp HL, Wong IY, Krishnan C, Malhotra S, Kennedy WA. Clinical presentation and urachal remnant pathology: implications for treatment. J Urol 2009;182:1921-1924.

31. Tian J, Ma JH, Li CL, Xiao ZD. Urachal mass in adults: clinical analysis of 33 cases. Zhonghua Yi Xue Za Zhi 2008;88:820-822.

Date added to bjui.org: 12/04/2011

DOI: 10.1002/BJUIw-2011-005-web

Spontaneous Regression of Metastatic Type II Papillary Renal Cell Carcinoma

March 30, 2011/by admin Z.9

We present the first reported case of metastatic type II papillary RCC with radiographic evidence of spontaneous regression at a non-pulmonary site of proven metastases.

Authors: Nicholas E. Power, Stephen A. Poon, Clarisse Mazzola, Jonathan L. Silberstein, Robert J. Motzer, Ana M. Molina, Snehal G. Patel, Jonathan A. Coleman. Department of Surgery, Urology Service, Memorial Sloan-Kettering Cancer Center, New York, NY 10065

Corresponding Author: Department of Surgery, Urology Service, Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Box 213, New York, NY10065. E-mail: [email protected]

Supported by The Sidney Kimmel Center for Prostate and Urologic Cancers and by funds provided by Renal Carcinoma Program Fund.

Abstract

Spontaneous regression of renal cell carcinoma (RCC) is a rare event that has been almost exclusively associated with the conventional clear cell subtype. We present the first reported case of metastatic type II papillary RCC with radiographic evidence of spontaneous regression at a non-pulmonary site of proven metastases. We highlight the literature on spontaneous regression of RCC and discuss the unique challenges of non-clear-cell metastatic RCC and new therapies in this setting.

Introduction

Spontaneous regression of renal cell carcinoma (RCC) is a rare event, with most large historic case series citing a 0-1.1% incidence [1]. In the majority of cases reported, metastasis was not confirmed histologically, and conventional clear cell RCC was the identified histology in the primary tumour [2]. Notably, spontaneous regression of papillary RCC (type 2) has been documented only once, at a site of pulmonary metastasis [3]. We report ona case of pT3bN2 high-grade type II papillary RCC in a 63-year-old male with histologically confirmed neck metastasis that spontaneously regressed following cytoreductive partial nephrectomy and retroperitoneal lymph node dissection. Subsequent lymphadenectomy of the site by left-neck dissection was performed following a period of surveillance during which no local or distant progression was identified. Pathology findings revealed 11/47 positive nodes that were consistent with the primary histology. Together with the recently described genetics of type II papillary RCC and the limitations of current systemic therapy in this setting, this case suggests opportunities for additional research.

Case Report

A 63-year-old male with a 30-year history of sarcoidosis presented with chest pressure of short duration which was investigated at a local emergency department. His cardiac evaluation was negative, but a chest x-ray suggested emphysematous changes and interstitial thickening in the upper lobe of the right lung. A non-contrast CT scan of the chest confirmed a non-specific interstitial pulmonary density in the right upper lobe and suggestion of cystic renal changes in the left kidney. A dedicated CT scan of the neck and chest identified a 4.0 X 3.1 X 3.2 cm (estimated volume 20.8 cc. Estimated tumour volumes are calculated volumes of an ellipsoid: (xyz)π/6) left thoracic inlet mass lateral to the thyroid (Figure 1) which was the only site of mild hypermetabolic activity on subsequent PET scan.

Figure 1a. A dedicated CT scan of the neck and chest.

Figure 1b. A dedicated CT scan of the neck and chest.

A dedicated CT scan of the neck and chest identified a 4.0 X 3.1 X 3.2 cm (estimated volume 20.8 cc. ) left thoracic inlet mass lateral to the thyroid which was the only site of mild hypermetabolic activity on subsequent PET scan.

A renal sonogram was interpreted to identify a 1.5 cm simple parapelvic cyst in the left kidney. On fine-needle aspirate of the neck mass, the immunoprofile was positive for CD10, CK7, and vimentin with cytoarchitecture considered suggestive of papillary carcinoma. CT urogram identified a 3.2-cm left lower-pole renal mass with a 2-cm left renal hilar lymph node and a 1.8-cm inter-aortocaval lymph node (Figure 2).

Figure 2a-d. CT urogram CT urogram identified a 3.2-cm left lower-pole renal mass with a 2-cm left renal hilar lymph node and a 1.8-cm inter-aortocaval lymph node

CT urogram identified a 3.2-cm left lower-pole renal mass with a 2-cm left renal hilar lymph node and a 1.8-cm inter-aortocaval lymph node

The patient was referred to our institution for further management. His history included prior treatment with corticosteroids for sarcoidosis and a family history remarkable for fatal childhood leukemia in 1 sibling and RCC in 2 first degree relatives including mother and 1 sibling. The details regarding tumoursubtype in these individuals were unavailable, though both had undergone nephrectomy without evidence of disease progression over >10 years of follow up. No familial history of symptomatic uterine fibroids or related abnormalities was evident. Pertinent physical examination findings werenotable for a firm, mobile, non-tender supraclavicular left neck mass, normal pulmonary examination, and no evidence of stigmata related to known genetic syndromes including dermatologic abnormalities. Genetic counseling and testing was recommended but declined. Following multi-disciplinary evaluation, cytoreductive robot-assisted laparoscopic partial nephrectomy and retroperitoneal lymph node dissection was performed. Pathology revealed 2.2 cm, pT3bN2 high-grade type II papillary RCC with foci of necrosis, renal hilar fat involvement and 14 of 25 nodes positive (Figures 3 and 4).

Figure 3

Pathology revealed 2.2 cm, pT3bN2 high-grade type II papillary RCC with foci of necrosis, renal hilar fat involvement and 14 of 25 nodes positive

Figure 4

Immunohistochemical stains revealed that the tumour was positive for CK7 and racemase, while negative for CA-IX, CD10, 34BE12, supporting the diagnosis.

In follow-up, a CT scan of the chest, abdomen, and pelvis was completed 6 weeks after surgery. In addition to post-surgical changes at the surgical site, decrease in size of the neck mass to 3.2 X 2.0 X 2.3 cm (estimated volume 7.7cc) was observed and no evidence of new metastases identified. The patient elected to forego systemic therapies and observe. (est. volume 5.4cc) and 2.3 X 1.9 X 1.4 cm (est. volume 3.2cc), respectively; Figure 5], with no evidence of local or distant disease progression identified.

Figure 5 a and b. CT scans completed 3 and 6 months postoperatively

(est. volume 5.4cc) and 2.3 X 1.9 X 1.4 cm (est. volume 3.2cc), respectively; Figure 5], with no evidence of local or distant disease progression identified. Figure 5. CT scans completed 3 and 6 months postoperatively

By RECIST 1.1 criteria [4], the neck mass regressed from 3.1 cm short axis to 1.9 cm short axis for a total of 39% response, or equivalent to a partial response (PR). As presurgical FDG-PET imaging did not correlate with all sites of proven tumour burden it was not used to evaluate sites of potential disease during follow-up.

After 11 months of surveillance with no evidence of progression or new metastasis, the patient underwent a selective left-neck dissection. This showed 4 positive nodes in neck levels IV and VI and 7 positive nodes from the left superior mediastinal dissection. These were all consistent, morphologically and immunohistochemically, with the primary type II papillary RCC. At his 3-month follow-up visit, there was no evidence of disease progression or new metastasis on CT scan of the neck, chest, abdomen, and pelvis, and he had recovered fully with only mild residual vocal hoarseness.

Discussion

Contemporary clinical assessment of tumour burden and response to cancer therapeutics is categorized according to the RECIST 1.1 guideline [4]. Spontaneous regression of cancer, as defined by Everson and Cole in 1966 however, is the “partial or complete disappearance of malignant tumour in the absence of all treatment or in the presence of therapy that is considered inadequate”[5]. Their manuscript identified 176 cases of spontaneous regression in multiple types of cancer, including 31 cases of RCC, the most common malignancy exhibiting this behavior. Unfortunately, 84% of the cases had histologic confirmation of the primary tumours but not the metastatic sites. This raises the possibility that the metastatic sites were actually of benign etiology. Contemporary histologic classification of renal tumoursthat now include the papillary type 2 subtype is also a relatively recent development raising the possibility of similar prior witnessed events which were documented differently. Publications have identified numerous cases of spontaneous regression of metastatic tumours, with the lungs being the most common site [5]. Others include brain, bone, liver, regional lymph nodes, and the adrenal glands [6, 7]. The event of cytoreductive intervention preceedingregression has prompted postulation of a humoral response capable of inducing tumour degeneration at the metastatic site. Cytoreductive nephrectomy was performed in approximately half of the reported cases, but other treatments, such as radiation, embolization, and radiofrequency ablation, have been implicated in the literature [5, 8]. The aetiology of spontaneous regression is unknown, but immunologic mechanisms have been hypothesized. In fact, spontaneous regression phenomena initially led to a surge in cytoreductive nephrectomy for advanced renal cancers. Significant complications and poor outcomes tempered the enthusiasm for this approach, but research to identify “biological response modifiers”, as coined in the original publications, continued. The cytokine era of immunotherapy developed out of these efforts, leading, with the discovery and elucidation of the VHL/VEGF pathway, to the current approach of molecular therapeutics [9].

Interestingly, manipulation of the primary tumour is not always required for spontaneous regression. In a clinical trial reported by Oliver et al. in 1989, 73 patients with metastatic RCC were placed on surveillance prior to being considered for therapy with interferon alpha [10].The trial was designed to remove the potential bias of tumour regression. Three complete responses, 2 partial responses, and 4 cases of stable disease >12 months were reported. The 5 cases of spontaneous regression comprised 7% of this cohort.

All published reports of spontaneous regression of RCC in which the histologic subtype was identified have been confirmed cases of clear cell RCC [2], except one recent report by Lim et al where a histologically confirmed pulmonary metastasis for papillary type II RCC arose 6 years after radical nephrectomy and subsequently regressed over the following year [3]. This case represents, to our knowledge, the first documented case of metastatic papillary RCC in a non-pulmonary site exhibiting regression. Metastatic clear cell RCC has experienced a revolution in management with development of targeted therapies. Metastatic papillary RCC, however, has proven resistant to these therapies [11, 12]. While localized papillary RCC carries a favorable prognosis, metastatic papillary RCC is associated with aggressive and rapidly fatal progression [13]. Genetic mutations have been identified with type II papillary RCC, now associated with the heritable condition of hereditary leiomyomatosis and renal cell carcinoma (HLRCC)as the syndromic model [14]. Mutation of fumarate hydratase (FH, a citric acid cycle enzyme catalyzing the conversion of fumarate to malate), localized to 1q42.3-43, has been implicated [14]. Wild type FH acts as a tumour suppressor; loss of heterozygosity studies revealed the loss of the wild type allele in these renal tumours, and there is low to absent enzymatic activity in patients with only leiomyomatosis [15]. However, unlike von Hippel-Lindau, Birt-Hogg-Dube (BHD) syndromes, or hereditary papillary RCC (HPRC), HLRCC kidney findings predominantly manifest as solitary and unilateral renal tumours with little penetrance, affecting 10-15% of HLRCC families (whereas 80-90% of VHL and HPRC families are affected by RCC) [15]. This finding suggests, according to the Knudsen two-hit hypothesis, the relative conservation and rare mutation event involving the wild-type allele leading to type II papillary RCC. The putative cause for regression of tumour at a nodal site of metastases in this case is speculative. Currently utilized agents targeted at the pathways of angiogenesis have been largely ineffective in metastatic papillary RCC[11, 12]. Conceptually, this is not as discouraging as it first appears; rather, it reveals potential avenues of research to identify signaling pathways specific to papillary RCC and, ultimately, to engineer more efficacious treatment for metastatic disease.

As a closing remark, the authors suggest that, in the absence of a more sensitive and specific definition of spontaneous regression of cancer than the one advocated by Everson and Cole in 1966, perhaps a better method may be proposed to stratify the degree of tumour biometric change along the spectrum of regression. One solution would be to adapt the RECIST 1.1 criteria used primarily to assess clinical response to cancer therapeutics. The presented case may be defined as a RECIST 1.1 spontaneous PR.This standard allows comparison across interventions, including clinical trials specific for papillary renal cancer[16]. Quantification of disease burden may also be calculatedusing tumour volume changes from imaging parameters of index tumoursto provide semi-quantitative data, estimated as 85% reduction in volume in this case (Figure 6).

Figure 6

Conclusion

Histologic and radiographic evidence of partial spontaneous regression of non-pulmonary metastatic type II papillary RCC is presented- the first published case so far as the authors are aware. In the context of the inefficacy of current systemic treatments and the recently described genetics of type II papillary RCC, this case suggests there are exciting opportunities for new research into this disease.

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Date added to bjui.org: 30/03/2011

DOI: 10.1002/BJUIw-2011-001-web