Category: Article of the Week

Article of the Week: Detecting SNs in patients with BCa intra-operatively

September 13, 2017/by admin Z.9

Every Week the Editor-in-Chief selects an Article of the Week from the current issue of BJUI. The abstract is reproduced below and you can click on the button to read the full article, which is freely available to all readers for at least 30 days from the time of this post.

In addition to the article itself, there is an accompanying editorial written by a prominent member of the urological community. This blog is intended to provoke comment and discussion and we invite you to use the comment tools at the bottom of each post to join the conversation.

If you only have time to read one article this week, it should be this one.

Radio-guided sentinel lymph node detection and lymph node mapping in invasive urinary bladder cancer: a prospective clinical study

Firas Aljabery^1,2,*, Ivan Shabo^2,3,4, Hans Olsson^2,5, Oliver Gimm^2,6 and Staffan Jahnson^1,2

¹Department of Urology, Region Östergötland, Linköping University Hospital, Linköping, Sweden, ²Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, sweden ³Endocrine and Sarcoma Surgery Unit, Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden ⁴Department of Breast and Endocrine Surgery, Karolinska University Hospital, Solna Stockholm, Sweden ⁵Department of Pathology, Region Östergötland, Linköping University Hospital, Linköping, Sweden ⁶Department of Surgery, Region Östergötland, Linköping University Hospital, Linköping, Sweden

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Abstract

Objectives

To investigate the possibility of detecting sentinel lymph nodes (SNs) in patients with urinary bladder cancer (BCa) intra-operatively and whether the histopathological status of the identified SNs reflected that of the lymphatic field.

Patients and Methods

We studied 103 patients with BCa pathological stage T1–T4 who were treated with cystectomy and pelvic lymph node (LN) dissection during 2005–2011 at the Department of Urology, Linköping University Hospital. Radioactive tracer Nanocoll 70 MBq and blue dye were injected into the bladder wall around the primary tumour before surgery. SNs were detected ex vivo during the operation with a handheld Geiger probe (Gamma Detection System; Neoprobe Corp., Dublin, OH, USA). All LNs were formalin-fixed, sectioned three times, mounted on slides and stained with haematoxylin and eosin. An experienced uropathologist evaluated the slides.

Results

The mean age of the patients was 69 years, and 80 (77%) were male. Pathological staging was T1–12 (12%), T2–20 (19%), T3–48 (47%) and T4–23 (22%). A mean (range) number of 31 (7–68) nodes per patient were examined, totalling 3 253 nodes. LN metastases were found in 41 patients (40%). SNs were detected in 83 of the 103 patients (80%). Sensitivity and specificity for detecting metastatic disease by SN biopsy (SNB) varied between LN stations, with average values of 67% and 90%, respectively. LN metastatic density (LNMD) had a significant prognostic impact; a value of ≥8% was significantly related to shorter survival. Lymphovascular invasion (LVI) occurred in 65% of patients (n = 67) and was significantly associated with shorter cancer-specific survival (P < 0.001).

Conclusion

We conclude that SNB is not a reliable technique for peri-operative localization of LN metastases during cystectomy for BCa; however, LNMD has a significant prognostic value in BCa and may be useful in the clinical context and in BCa oncological and surgical research. LVI was also found to be a prognostic factor.

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Editorial: Positive messages for bladder cancer management in negative sentinel lymph node study

September 13, 2017/by admin Z.9

I encourage you to read the study by Aljabery et al. [1] in this edition of BJUI. Their findings are based on some very solid methodology and I think provide a robust answer to their question, which often in science means a ‘negative’ result. The principle of sentinel lymph node biopsy (SLNB) needs no introduction. It is primarily intended to detect the principal LN draining a tumour, allowing its removal and pathological determination of LN metastasis status in that individual [2].The avoidance of an unnecessary LN dissection (LND) and its associated risks is at the heart of any SLNB strategy. On the other hand, particularly for bladder cancer, there is a recognition that a higher number of LNs removed at the time of surgery confers a survival advantage to patients through more accurate staging [3]. With greater numbers of LNs removed pN0 patients are more likely to be truly N0 and pN1 patients with limited metastases have a greater chance that all disease has been completely excised. Thus, when considering SLNB in bladder cancer there is the usual conflict between maximising oncological benefit and minimising surgical harm.Aljabery et al. [1] present an excellent series of cystectomies with a 100% negative margin rate and mean LN count of 30. The 40% rate of LN involvement, is perhaps partly due to the meticulous triple sectioning of each excised LN. Their SLN technique involved four cystoscopic injections to the bladder wall surrounding the tumour and focused on the biggest lesion in multiple tumour cases. The LNs were removed in their packets and studied after removal from the patient. While this is likely to be a more precise method for determining the site of the SLN, it clearly differs from the approach one would take if trying to avoid LND in negative-SLN cases. Furthermore, examination of LNs was performed after formalin fixation. Typically when using SLN techniques frozen sections are also used to guide surgeons during surgery.The results clearly show that SLNB using radiolabelled nanocolloid does not allow accurate identification of pathologically LN-negative patients who could then avoid a complete LN dissection. Sensitivity of the technique in the detection of positive LNs ranged from 67% to 90% at the various LN stations. Overall, of patients with an identifiable SLN that was negative, 19% of patients had positive LNs elsewhere (81% negative predictive value). Effectively one in five patients who might be reassured by a negative SLN result would in fact have undetected positive LNs left behind if this technique were employed. Furthermore, this estimation does not consider errors likely to be introduced with in situ SLN identification and the use of frozen-section analysis rather than non-time-critical analysis of formalin-fixed sections.In such a dangerous disease such inaccuracy is not tolerable and so I totally agree with the authors’ [1] findings that SLNB of pelvic LNs at the time of radical cystectomy for bladder cancer is not a reliable technique for identifying LN metastasis.The positive messages from this study [1] are worth noting by those learning and undertaking cystectomy. The authors’ meticulous approach to surgery is evident from the methodology described and the accumulation of such a well-characterised series. This must be a contributing factor in achieving a 100% negative surgical margin rate and such consistently high LN yields. This should certainly be the aim of all cystectomists. The appropriate time, skill and patience should be given to this step and it should not be compromised upon, particularly when developing robot-assisted or laparoscopic cystectomy services.The findings that T-stage, N-stage and lymphovascular invasion are linked to survival are not that surprising. However, the use of LN metastatic density as a prognostic marker is interesting, as it is not usually discussed in our multidisciplinary meetings. This measure incorporates nodal tumour burden and the extent of LND. The finding of better outcomes in those with a LN metastatic density of <8% reinforces the message that even in those with LN metastases, removing greater numbers of LNs may improve prognosis. Furthermore, the finding that 30% of unilateral LN-positive tumours also had contralateral LNs settles any arguments for unilateral LN dissections.In a recent systematic review of SLNB in bladder cancer [4], the negative predictive value was found to be 92% compared to 81% in the Aljabery et al. [1] study. The authors of the systematic review suggested that SLNB is a promising technique; perhaps in view of technology advances they reviewed that might improve future outcomes of SLNB. While improvements may be possible, current evidence would not encourage me to consider SLNB using radiolabelled nanocolloid for fear of impairing cancer outcomes.

Congratulations to Aljabery et al. [1] on their work. I hope you find reading their paper as constructive as I did.

Tim Dudderidge
Department of Urology, University Hospital Southampton,
Southampton, Hampshire, UK

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References

1 Aljabery F, Shabo I, Olson H, Gimm O, Jahnson S. Radio-guided sentinel lymph node detection and lymph node mapping in invasive urinary bladder cancer: a prospective clinical study. BJU Int 2017; 120: 329–36

2 Gould EA, Winship T, Philbin PH, Kerr HH. Observations on a “sentinel node” in cancer of the parotid. Cancer 1960; 13: 77–8

3 Koppie TM, Vickers AJ, Vora K, Dalbagni G, Bochner BH. Standardization of pelvic lymphadenectomy performed at radical cystectomy. Cancer 2006; 107: 2368–74

4 Liss M, Noguchi J, Lee H, Vera D, Kader AK. Sentinel lymph node biopsy in bladder cancer: systematic review and technology update. Indian J Urol 2015; 31: 170–5

Video: Detecting SNs in patients with BCa intra-operatively

September 13, 2017/by admin Z.9

Radio-guided sentinel lymph node detection and lymph node mapping in invasive urinary bladder cancer: a prospective clinical study

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Abstract

Objectives

Patients and Methods

Results

Conclusion

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Article of the Week: sRPLND+PLND for ‘node-only’ recurrent PCa

September 6, 2017/by admin Z.9

If you only have time to read one article this week, it should be this one.

Robotic salvage retroperitoneal and pelvic lymph node dissection for ‘node-only’ recurrent prostate cancer: technique and initial series

Andre Abreu*, Carlos Fay*†, Daniel Park*, David Quinn*, Tanya Dorff*,John Carpten*, Peter Kuhn*, Parkash Gill*, Fabio Almeida* and Inderbir Gill*

*University of Southern California (USC) Institute of Urology, Catherine & Joseph Aresty Department of Urology, Keck School of Medicine, USC, Los Angeles, CA, USA, and †Pontiﬁcal Catholic University of Rio Grande do Sul, Porto Alegre, Brazil

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Abstract

Objectives

To describe the technique of robot-assisted high-extended salvage retroperitoneal and pelvic lymphadenectomy (sRPLND+PLND) for ‘node-only’ recurrent prostate cancer.

Patients and Methods

In all, 10 patients underwent robot-assisted sRPLND+PLND (09/2015–03/2016) for ‘node-only’ recurrent prostate cancer, as identified by ¹¹C-acetate positron emission tomography/computed tomography imaging. Our anatomical template extends from bilateral renal artery/vein cranially up to Cloquet’s node caudally, completely excising lymphatic-fatty tissue from aorto-caval and iliac vascular trees; RPLND precedes PLND. Meticulous node-mapping assessed nodes at four prospectively assigned anatomical zones.

Results

The median operative time was 4.8 h, estimated blood loss 100 mL and hospital stay 1 day. No patient had an intraoperative complication, open conversion or blood transfusion. Three patients had spontaneously resolving Clavien–Dindo grade II postoperative complications. The mean (range) number of nodes excised per patient was 83 (41–132) and mean (range) number of positive nodes per patient was 23 (0–109). Seven patients (70%) had positive nodes on final pathology. Node-positive rates per anatomical level I, II, III and IV were 28%, 32%, 33% and 33%, respectively. In patients with positive nodes, the median PSA level had decreased by 83% at the 2-month follow-up.

Conclusion

The initial series of robot-assisted sRPLND+PLND is presented, wherein we duplicate open surgery with superior nodal counts and decreased morbidity. Robot-assisted technical details for an anatomical LND template up to the renal vessels are presented. Longer follow-up is necessary to assess oncological outcomes.

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Editorial: sLND – if yes, Robotics?

September 6, 2017/by Francesco Montorsi

The manuscript in this issue of the BJUI by de Castro Abreu et al. [1] reports the results of the first series of patients to undergo robotic-assisted salvage lymph node dissection (sLND) for nodal recurrence of prostate cancer. Despite the absence of a high level of evidence, sLND has been gaining attention in recent years. Indeed, several series have shown promising results of such an approach, especially in terms of PSA response to surgery and delay in clinical recurrence [2-4]. However, sLND is a complex surgery and is not devoid of complications, as in up to 13.8% of patients Clavien–Dindo ≥IIIa complications occur [5]. When analysing the results of the current manuscript [1], it is impressive to read that the mean number of LNs removed was 83, ranging from 41 to 132, which is significantly higher than the reported figures of open sLND series. Moreover, despite the long median operative time (4.8 h), complication rates and postoperative course were excellent as compared to previously published series, although a direct comparison between the open and robot-assisted approach should be only addressed in prospective studies. The authors should be congratulated on the superb results obtained during the learning curve of such complex surgery, but some issues need to be discussed.

First, it is difficult to understand whether such results apply only to very expert surgeons. In other words, is it possible to translate such surgery to less experienced robotic surgeons? Second, is it necessary to extend the LND to a similar extent in all cases? Previous reports have shown that patients with retroperitoneal involvement may not benefit from sLND as much as their counterparts with only pelvic involvement [2]. The authors [1] show no significant impact of such an extended approach on complications and postoperative course, but the invasiveness of such an extended approach needs to be justified in each case. Third, the introduction of new tracer methods, such as prostate-specific membrane antigen (PSMA) positron emission tomography/CT, with higher specificity for prostate cancer may reduce the need for such extended templates, without compromising the oncological results [6]. Fourth, is the robotic approach feasible and safe in patients previously submitted to radical prostatectomy independently from the approach (open vs laparoscopic/robotic), from the extent of the previous LND, as well as from the previous administration of adjuvant/salvage radiotherapy? All these answers will need to be addressed in future studies on subgroups of patients undergoing sLND. Most importantly, until a high level of evidence is available, sLND should still be considered experimental and should be performed by highly experienced surgeons.

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Nazareno Suardi and Francesco Montorsi

Department of Urology, Urological Research Institute, Vita –Salute San Raffaele University, Milan, Italy

References

1 Abreu A, Fay C, Park D et al. Robotic salvage retroperitoneal and pelvic lymph node dissection for ‘node-only’ recurrent prostate cancer: technique and initial series. BJU Int 2017; 120: 401–8

2 Suardi N, Gandaglia G, Gallina A et al. Long-term outcomes of salvage lymph node dissection for clinically recurrent prostate cancer: results of a single-institution series with a minimum follow-up of 5 years. Eur Urol 2015; 67: 299–309

3 Ost P, Bossi A, Decaestecker K et al. Metastasis-directed therapy of regional and distant recurrences after curative treatment of prostate cancer: a systematic review of the literature. Eur Urol 2015; 67: 852-63

4 Ploussard G, Almeras C, Briganti A et al. Management of node only recurrence after primary local treatment for prostate cancer: a systematic review of the literature. J Urol 2015; 194: 983–8

5 Abdollah F, Briganti A, Montorsi F et al. Contemporary role of salvage lymphadenectomy in patients with recurrence following radical prostatectomy. Eur Urol 2015; 67: 839–49

6 van Leeuwen PJ, Stricker P, Hruby G et al. (68) Ga-PSMA has a high detection rate of prostate cancer recurrence outside the prostatic fossa in patients being considered for salvage radiation treatment. BJU Int 2016;117:732–9

Infographic: Long-term sexual health outcomes in men with classic bladder exstrophy

September 6, 2017/by admin Z.9

Infographic: Long-term sexual health outcomes in men with classic bladder exstrophy

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Article of the Month: Long-term sexual health outcomes in men with classic bladder exstrophy

August 30, 2017/by admin Z.9

Every Month the Editor-in-Chief selects an Article of the Month from the current issue of BJUI. The abstract is reproduced below and you can click on the button to read the full article, which is freely available to all readers for at least 30 days from the time of this post.

In addition to the article itself, there is an accompanying editorial written by a prominent member of the urological community. This blog is intended to provoke comment and discussion and we invite you to use the comment tools at the bottom of each post to join the conversation.

If you only have time to read one article this week, it should be this one.

Long-term sexual health outcomes in men with classic bladder exstrophy

Timothy S. Baumgartner, Kathy M. Lue, Pokket Sirisreetreerux, Sarita Metzger, Ross G. Everett, Sunil S. Reddy, Ezekiel Young, Uzoma A. Anele, Cameron E. Alexander, Nilay M. Gandhi, Heather N. Di Carlo and John P. Gearhart

Division of Pediatric Urology, James Buchanan Brady Urological Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA

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Abstract

Objectives

To identify the long-term sexual health outcomes and relationships in men born with classic bladder exstrophy (CBE).

Men’s reproductive health issues is often ignored and not prioritized in modern society. Male individuals sometimes resort to finding alternative solutions to their own problems and one in particular has helped them achieve sexual fulfillment. Prostate stimulation has helped in the prevention of such diseases using unconventional tools and methods. Lovehoney UK coupons have helped many to try out and explore other forms of expression and treatment using sex toys that stimulate the prostate. Here you will get a best penis extender device by Maleedge, visit once. For those interested, check out their website and you can also find many of their discounts and coupons with a quick search online. There are many places to buy sex toys, but if one or both persons are nervous about it, buying them online is a fantastic option. Buying sex toys online allows you to see detailed colour, vivid photographs of all the Sex Toys you could ever want without having to go into an adult store!

Materials and Methods

A prospectively maintained institutional database comprising 1248 patients with exstrophy-epispadias was used. Men aged ≥18 years with CBE were included in the study. A 42-question survey was designed using a combination of demographic information and previously validated questionnaires.

Results

A total of 215 men met the inclusion criteria, of whom 113 (53%) completed the questionnaire. The mean age of the respondents was 32 years. Ninety-six (85%) of the respondents had been sexually active in their lifetime, and 66 of these (58%) were moderately to very satisfied with their sex life. The average Sexual Health Inventory for Men score was 19.8. All aspects of assessment using the Penile Perception Score questionnaire were on average between ‘very dissatisfied’ and ‘satisfied’. Thirty-two respondents (28%) had attempted to conceive with their partner. Twenty-three (20%) were successful in conceiving, while 31 (27%) reported a confirmed fertility problem. A total of 31 respondents (27%) reported undergoing a semen analysis or post-ejaculatory urine analysis. Of these, only four respondents reported azoospermia.

Conclusion

Patients with CBE have many of the same sexual and relationship successes and concerns as the general population. This is invaluable information to give to both the parents of boys with CBE, and to the boys themselves as they transition to adulthood. See article from PlugLust and learn one way to prevention.

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Editorial: Sexuality in men with exstrophy

August 30, 2017/by admin Z.9

It is always exciting to get new data on exstrophy from Johns Hopkins, but especially when sexual development is the subject [1]. It is the only unit with enough patients on continuous follow-up to overcome the difficulties of researching such a rare condition.

In the last 40 years, patients born with exstrophy have achieved a near normal life-expectancy. Reconstructive techniques for the bladder are now such that incontinence is rare, although often bladder emptying depends on clean intermittent self-catheterisation [2]. As with all fit young men, their minds turn frequently to sex and, occasionally, its natural consequence – pregnancy.

Current data have established that the men have a normal libido, orgasms, and erections. It is probable that the testes are normal at birth but often are damaged by recurrent infections. The penis is short, broad and has a characteristic chordee. Other erectile deformities are probably the result of corporeal damage during reconstruction in infancy. Most of these are surgically correctable. Ejaculation is poor or absent [3, 4].

Data on the men’s own satisfaction are contradictory and there are none on the partner’s opinions. Masturbation is almost universal. The incidence of erectile dysfunction is more than double that of controls (58% vs 23%) [3]. Much the commonest cause is fear of rejection by a partner because of the obvious penile anomalies. Most series show that men like to establish a good partnership before starting intercourse, although at least one group report that random and short-term relationships are common [5]. Unfortunately the published series are small and few of them address sexuality in a structured manner.

At Johns Hopkins the exstrophy database now has >1 200 patients and there is a programme for close and indefinite review. This is good for the patients and good for outcomes research. Sexual function has been investigated in 113 adult men (53% of those eligible) using a 42-question survey, which incorporated four validated instruments and additional questions related to sexuality [1].

In all, 85% had been sexually active at some time and 62% were currently in a relationship; three were homosexual and three bisexual. The divorce rate was lower than the norm in the USA! Amongst much other data, it was found that only 58% were moderately-to-very satisfied with their sex life. The mean penile perception score (PPS) was 6.2 (maximum possible 12) and most men were dissatisfied with their penile appearance to some degree. However, there was no relationship between the PPS and sexual activity or satisfaction. In all, 32 of 113 men had tried to achieve a pregnancy, of whom 72% were successful, with half of them requiring reproductive technology. Another 27% had a confirmed fertility problem.

With these new data, we can say that men born with exstrophy have a normal ambition for their sexual activity and form solid partnerships. Their overall level of satisfaction is lower than normal and the appearance of the penis is a major contributory cause. The fertility rate is significantly lower than normal. We still know nothing about the feelings of the partners.

Can anything be done to improve this situation? On the positive side, correction of the penile deformities, prompt management of urinary infections (to avoid epididymo-orchitis), and reproductive technology are helpful. It is most important not to damage the penis or its nerve supply during reconstructive surgery. At present, there are inadequate data to say whether the formation of a new phallus incorporating the native penis (similar to female–male gender reassignment) would generally be beneficial [6]. Psycho-sexual support is often recommended but the techniques used and outcomes rarely reported. However, paediatric and adolescent urologists have a vital role in discussing sexual function with their patients, encouraging ‘normality’ and providing practical help when possible.

Christopher R.J. Woodhouse

Emeritus Professor of Adolescent Urology, University College London, UK

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References

1 Baumgartner TS, Lue KM, Sirisreetreerux P et al. Long-term sexual health outcomes in men with classic bladder exstrophy. BJU Int 2 017; 120: 422– 7

2 Woodhouse CR, North A, Gearhart J. Standing the test of time: a long term outcome of reconstruction of the exstrophy bladder. World J Urol 2006; 24: 244–9

3 Castagnetti M, Tocco A, Rigamonti W, Artibani W. Sexual function in men born with classic bladder exstrophy: a norm related study. J Urol 2010; 183: 1118–22

4 Woodhouse CR. Exstrophy and epispadias. In Adolescent Urology and Long-Term Outcomes, Oxford: Wiley Blackwell: 2015, pp 128–53

5 Ben-Chaim J, Jeffs RD, Reiner WG, Gearhart JP. The outcome of patients with classic exstrophy in adult life. J Urol 1996; 155: 1251–2

6 Massanyi EZ, Gupta A, Goel S et al. Radial forearm free ﬂap phalloplasty for penile inadequacy in patients with exstrophy. J Urol 2013; 190(Suppl.): 1577–82

Article of the Week: Sentinel node biopsy for prostate cancer: report from a consensus panel meeting

August 23, 2017/by admin Z.9

If you only have time to read one article this week, it should be this one.

Sentinel node biopsy for prostate cancer: report from a consensus panel meeting

Henk G. van der Poel* , Esther M. Wit*, Cenk Acar†, Nynke S. van den Berg‡,Fijs W. B. van Leeuwen‡, Renato A. Valdes Olmos‡, Alexander Winter§,Friedhelm Wawroschek§, Fredrik Liedberg¶**, Steven Maclennan††and Thomas Lam†† On behalf of the Sentinel Node Prostate Cancer Consensus Panel Group members

*Department of Urology, Netherlands Cancer Institute, Amsterdam, The Netherlands, †Department of Urology, Eryaman Hospital, Ankara, Turkey, ‡Department of Radiology, University of Leiden Medical Centre, Leiden, The Netherlands, §Klinikum Oldenburg, School of Medicine and Health Sciences, University Hospital for Urology, Oldenburg, Germany, ¶Department of Urology, Skane University Hospital, Malmo, **Department of Translational Medicine Lund University, Lund, Sweden, and ††Academic Urology Unit, University of Aberdeen, Aberdeen, UK

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Abstract

Objective

To explore the evidence and knowledge gaps in sentinel node biopsy (SNB) in prostate cancer through a consensus panel of experts.

Methods

A two-round Delphi survey among experts was followed by a consensus panel meeting of 16 experts in February 2016. Agreement voting was performed using the research and development project/University of California, Los Angeles Appropriateness Methodology on 150 statements in nine domains. The disagreement index based on the interpercentile range, adjusted for symmetry score, was used to assess consensus and non-consensus among panel members.

Results

Consensus was obtained on 91 of 150 statements (61%). The main outcomes were: (1) the results from an extended lymph node dissection (eLND) are still considered the ‘gold standard’, and sentinel node (SN) detection should be combined with eLND, at least in patients with intermediate- and high-risk prostate cancer; (2) the role of SN detection in low-risk prostate cancer is unclear; and (3) future studies should contain oncological endpoints as number of positive nodes outside the eLND template, false-negative and false-positive SN procedures, and recurrence-free survival. A high rate of consensus was obtained regarding outcome measures of future clinical trials on SNB (89%). Consensus on tracer technology was only obtained in 47% of statements, reflecting a need for further research and standardization in this area. The low-level evidence in the available literature and the composition of mainly SNB users in the panel constitute the major limitations of the study.

Conclusions

Consensus on a majority of elementary statements on SN detection in prostate cancer was obtained.; therefore, the results from this consensus report will provide a basis for the design of further studies in the field. A group of experts identified evidence and knowledge gaps on SN detection in prostate cancer and its application in daily practice. Information from the consensus statements can be used to direct further studies.

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Editorial: Sentinel nodes in prostate cancer– are we chasing a ghost?

August 23, 2017/by admin Z.9

Van der Poel et al. [1] report the findings of a consensus panel meeting on sentinel node (SN) biopsy at the time of radical prostatectomy. The consensus process was based on a two-round Delphi survey on the current evidence and knowledge gaps on SN detection. Then, a number of experts among those who answered the survey were invited to further discuss these issues during a consensus meeting.

The authors are to be complimented on their effort to establish standard definitions, techniques, and reporting of outcomes of SN detection. Their results push the field forward and will make it possible to compare future data between institutions, individual surgeons, and techniques of SN detection. Nevertheless, although the authors admittedly represented a group of potentially biased experts, current limitations of SN detection were fairly acknowledged.

One thorny issue remains, the definition of SN and whether a true SN exists or not. The SN concept implies that one should reliably find tumour in the first echelon of drainage when tumour is present. The SN concept further assumes that if the SN is free of tumour, then so are the next drainage stations. Does that really happen in prostate cancer? We know from previous mapping studies that primary lymphatic landing sites of the prostate are heterogeneously localised, that drainage varies from site to site of tracer injection (and thus tumour location), and that drainage varies from patient to patient [2, 3]. Thus, prostate cancer does not fit the Halstedian paradigm of a pre-defined, stepwise, uniform pathway of metastatic spread. An additional setback of SN detection is that lymph nodes that contain a large tumour burden often fail to take up the tracer [2, 4]. One might critically argue that this limitation may be dependent on the tracer used. The consensus group could not conclusively agree on which tracer technology to use. Looking forward, imaging probes that target tumour-specific molecules may improve tumour detection during pelvic lymph node dissection (PLND). The prostate-specific membrane antigen (PSMA) represents a particularly promising marker in prostate cancer imaging. However, using ⁶⁸Ga-PSMA-positron emission tomography/CT for the detection of lymph node metastases before radical prostatectomy, one group failed to observe the expected improvement and reported only 33% sensitivity [5]. Future studies will determine whether these advances in prostate cancer detection will translate into more precise targeted dissection of lymph node metastases.

Altogether, the consensus group concluded that extended PLND should remain the standard of care, at least in patients with intermediate- and high-risk prostate cancer. This conclusion is laudable, but to be fair, we have no level 1 evidence for this either. However, every oncology-oriented surgeon would agree that each potential positive lymph node should be found and removed during surgery with curative intent. In case of true low-risk prostate cancer, this is probably less of an issue, but it should be mentioned that this population is at very low risk of dying from prostate cancer, even if left untreated, and the indication for radical prostatectomy should be questioned rather than that for PLND. Furthermore, pathological Gleason score is underestimated in preoperative biopsies in ~30% of all cases [6], making the decision to perform PLND or not in low-risk disease difficult.

Again, the authors should be complimented for their thorough work. We still do not know whether the SN exists, but performing surgery with image-guidance provides quality control for completeness of resection and might help detect (positive?) lymph nodes outside of the extended PLND template. Indeed, up to 35% of prostate lymphatic drainage sites may remain outside the extended anatomical template [3]. SN detection might also teach us when and where to stop dissection to decrease potential morbidity of PLND without leaving tumour behind. Thus, chasing the ghost of the SN has made and makes us better and more meticulous cancer surgeons. At the same time, it is humbling that we have been chasing a ghost for so long without bringing up level 1 evidence.

George N. Thalmann and Daniel P. Nguyen

Department of Urology, University Hospital Bern, Bern, Switzerland

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References

1 van der Poel HG, Wit EM, Acar C et al. Sentinel node biopsy for prostate cancer: report from a consensus panel meeting. BJU Int 2017; 120: 204–11

2 Nguyen DP, Huber PM, Metzger TA, Genitsch V, Schudel HH, Thalmann GN. A speciﬁc mapping study using ﬂuorescence sentinel lymph node detection in patients with intermediate- and high-risk prostate cancer undergoing extended pelvic lymph node dissection. Eur Urol 2016; 70: 734–7

3 Mattei A, Fuechsel FG, Bhatta Dhar N et al. The template of the primary lymphatic landing sites of the prostate should be revisited: results of a multimodality mapping study. Eur Urol 2008; 53: 118–25

4 Weckermann D, Dorn R, Holl G, Wagner T, Harzmann R. Limitations of radioguided surgery in high-risk prostate cancer. Eur Urol 2007; 51: 1549–58

5 Budaus L, Leyh-Bannurah SR, Salomon G et al. Initial experience of 68Ga-PSMA PET/CT imaging in high-risk prostate cancer patients prior to radical prostatectomy. Eur Urol 2015; 69: 4–7

6 Moussa AS, Kattan MW, Berglund R, Yu C, Fareed K, Jones JS.A nomogram for predicting upgrading in patients with low- and intermediate-grade prostate cancer in the era of extended prostate sampling. BJU Int 2010; 105: 352–8