Scrotal leiomyosarcoma
A case of a 30 year old male presented with a slowly-enlarging, painless lump on the skin of his left hemiscrotum.
Authors: Quinlan, Mark1; D’Arcy, Frank1; Corcoran, Shane1; Casey, Mary1; Harding, Brian2; Hussey, Alan1; Durkan, Garrett1
1. University College Hospital Galway, Ireland
2. Portiuncula Hospital, Ballinasloe, Galway, Ireland
Corresponding Author: Mark Quinlan, University College Hospital Galway, Ireland. Email: [email protected], [email protected]
Case history
A 30 year old male presented with a slowly-enlarging, painless lump on the skin of his left hemiscrotum. It had been present for approximately six months. He had no significant medical history. He had a 10-pack year smoking history. Two maternal aunts had been treated for breast cancer and a grandfather had died of lung cancer. Following examination, the clinical impression was of a 3cm benign sebaceous cyst. There was no inguinal lymphadenopathy. At the presenting hospital, the lesion was excised under local anaesthetic (see Figure 1).
Figure1. Site of initial excision
Surprisingly, the histopathologist reported a well to moderately differentiated leiomyosarcoma with a high mitotic rate (see Figures 2 and 3).
Figure 2. Histology shows parallel arrays of eosinophilic fascicles of malignant spindle cells. Individual cells are slender or slightly plump.
Figure 3. High power photomicrograph of cytologic features showing eosinophilic cytoplasm and blunt-ended nuclei. Occasional cells have perinuclear vacuoles. Two mitotic figures are present (arrow)
A staging CT scan of thorax, abdomen and pelvis was negative for metastases. He was referred to our institution for further management.
Following review at the Uro-Oncology MDT meeting, wide local excision (WLE) was recommended. Prior to surgery, he underwent a scrotal ultrasound which was unremarkable. WLE with 3cm circumferential margins was carried out (see Figure 4).
Figure 4. WLE specimen
Frozen section confirmed the margins were negative and there was no residual tumour apparent. The wound was closed primarily without the need for grafting or reconstruction. A further, small cystic lesion was excised from the posterior scrotum (see Figure 5). There were no post-operative complications.
Figure 5. Primary closure of WLE defect with posterior cyst excision below (arrow)
Final histology revealed patchy chronic inflammation and giant cell reaction to suture material. There was no residual leiomyosarcoma. The smaller, posterior scrotal lesion was an epidermal cyst with an acute and chronic granulomatous inflammatory reaction. There was no evidence of malignancy. A medical oncology opinion was sought, and no adjuvant treatment was advised. However, regular, lifelong clinical follow-up with appropriate imaging is indicated.
Discussion
Primary cutaneous leiomyosarcoma is an uncommon malignancy with a predilection for the lower extremities [1]. Pure scrotal leiomyosarcomas are particularly rare. To the best of our knowledge, it has never previously been described in Ireland. Only 30 cases have been reported in the world literature. It typically occurs in middle-aged/elderly men. It presents as a painless, slow-growing, cutaneous lesion and often resembles a cyst [2]. It is easily mistaken for a benign condition. The lymphatic drainage is to the inguinal and iliac nodes.
An aggressive initial resection with wide margins is required. Debate exists as to the optimal extent of an oncologically safe margin, chiefly because of the rarity of the tumour and the lack of randomised studies. McKee et al. showed that the local recurrence-free interval at 5 years for soft tissue sarcomas was higher with a margin of >10 mm (84%) than margins of 1–9 mm (58%) [3]. Inguinal lymph node dissection is not routinely advocated, unless there is a high degree of suspicion for lymph node metastases. Some argue that compared to leiomyosarcomas arising from other locations, aggressive evolution is not habitual in the scrotum [4]. Nonetheless, long-term follow-up of patients with cutaneous leiomyosarcoma is mandatory to detect local recurrence and distant metastases that can occur years after the initial excision [2]. Recurrence most commonly tends to be local but distant metastases in the bones and lungs have been reported [4, 5].
Conflict of interest statement
The authors declare that there are no conflicts of interest
References
[1] Limaiem F, Chelly I, Bellil S, Mekni A, Nidhameddine K, Haouet S, Bellil K, Zitouna M. Primary cutaneous leiomyosarcoma: a histological and immunohistochemical study of 4 cases. Pathologica. 2007 Dec;99(6):415-9.
[2] John T, Portenier D, Auster B, Mehregan D, Drelichman A, Telmos A. Leiomyosarcoma of scrotum – case report and review of literature. Urology. 2006 Feb;67(2):424.e13-424.e15. Review.
[3] McKeeMD, Dong Feng Liu, Brooks J, et al. The prognostic significance of margin width for extremity and trunk sarcoma. Journal of Surgical Oncology. 2004;85:68– PubMed ;76.
[4] Diz Rodríguez MR, Vírseda Chamorro M, Ramírez García JR, Merino Royo E, Moreno Reyes A, Paños Lozano P. Scrotal leiomyosarcoma with bone metastasis]. Actas Urol Esp. 2006 Jun;30(6):638-40. Review.
[5] Johnson H Jr. Leiomyosarcoma of scrotum. Urology 29:436-438, 1987.
Date added to bjui.org: 18/10/2011
DOI: 10.1002/BJUIw-2011-056-web