Dr. Finelli presented the reasons for supporting enucleation of this type of tumor. These include parenchyma preservation, avoidance of complications, and safety. Dr. Finelli rightfully stated that when we cannot decide whether radical nephrectomy truly causes harm, discussion of a 1-2 mm margin vs. no margin during partial nephrectomy is somewhat unexciting. When assessing the complication rate, data has shown that there is no difference in the blood loss, positive margins rate, urine leak, blood transfusion, major complications, renal function, recurrence, or survival, between enucleation and excision1. Finally, the issue of safety of enucleation was discussed. Dr. Finelli presented a study of 82 kidneys treated with radical nephrectomy for a tumor <4 cm. In this study, following radical nephrectomy. step sectioning was performed at 3 mm intervals. Amazingly, 31.7% of kidneys were lacking fully intact pseudocapsules, and even more, interestingly, 19.5% demonstrated to have cancer beyond the pseudo capsule! with 12.2% showing a tumor entering normal parenchyma, 2.4% entering a venule, and 4.9% being a satellite tumor. This high percentage of cancer beyond the pseudocapsule has also been shown in another study3.
Incorporating these data together, Dr. Finelli concluded that there are no good reasons to enucleate small renal tumors. Furthermore, the safety of enucleation data is dominated by low-grade cohorts and follow-up of fewer than 5 years. It is also important to remember that positive surgical margins rates increase recurrence rates by 10%4,5.
Dr. Finelli concluded his concise and elegant talk, stating that enucleation is common (even when not intended). The deliverables of enucleation are unclear and debatable. Lastly, the risk of enucleation is very clear and significantly raises the rate of positive surgical margins. Therefore, rather than debate which surgical approach to applying to small renal masses, partial nephrectomy should be personalized and driven by imaging, clinical scenario, and renal biopsy information.
Presented by: Antonio Finelli, MD, FRCSC, MSc, Princess Margaret Cancer Center, Toronto, Ontario, Canada
1. Mukkamal A et al. Urology 2014
2. Li et al. European Urology 2003
3. Snarskis C. et al. J Urol 2017
4. Bernhard JC et al. Eur Urol 2010
5. Khalifeh A et al. J Urol 2013
Written by: Hanan Goldberg, MD, Urologic Oncology Fellow, SUO, University of Toronto, Princess Margaret Cancer Centre, @GoldbergHanan, at the 19th Annual Meeting of the Society of Urologic Oncology (SUO), November 28-30, 2018 – Phoenix, Arizona
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