Dr. Aherling then moved on to discuss the effect that surgical volume, experience, and technique have on PSM rate. A study published by Dr. James Estham examined variations among individual surgeons in the rate of PSM. This paper demonstrated that the technique used by the individual surgeon is a significant factor. Lower rates of PSM were seen for high volume surgeons, suggesting that experience and careful attention to surgical details, can significantly decrease the PSM rates and improve cancer control with radical prostatectomy.1
The location and extent of PSM have an impact on BCR, but little effect on long term cancer specific survival (CSS). A study by Stephenson et al. has examined this question and has not found a clinically significant difference. 2 This calls into question the rationale for postoperative radiotherapy for PSMs in the absence of other adverse features such as seminal vesicle invasion, pathologic Gleason score of 8-10, or a short PSA doubling time after BCR. Secondly, it calls into question the relevance of PSM rates as a measure of surgical proficiency.
Next, Dr. Aherling moved on to discuss nerve sparing and the apex. Gentle handling of these tissues will lead to improved continence. It is important to lower the amount of traction used, as this will lead to earlier potency recovery. Dr. Aherling also reports that in his own institution, after changing the assistant to a dedicated nurse practitioner, has caused a significant improvement in outcomes. Another important factor for continence is the membranous urethral length (MUL) (Figure 1). A MUL of more than 1.5 cm demonstrated to lead to higher 30 day continence rate compared to a MUL of less than 1.5 cm. There is also data showing that 2 year potency outcomes are considerably better for athermal technique vs. thermal technique.
In conclusion, management of dorsal vein complex (DVC) and most importantly urethral length, impact outcomes. Management of the DVC and distal neurovascular bundles dramatically impact recovery of erections. Oncological outcomes are not compromised with maximal preservation of the DVC and urethral length.
Figure 1 - Membranous urethral length

Presented By: Thomas Ahlering, California, USA
Written By: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre @GoldbergHanan at the 2018 North American Robotic Urology Symposium, February 16-17, 2018 - Las Vegas, NV
References:
1. Eastham JA, Kattan MW, Riedel E, et al. Variations among individual surgeons in the rate of positive surgical margins in radical prostatectomy specimens. The Journal of urology 2003; 170(6 Pt 1): 2292-5.
2. Stephenson AJ, Eggener SE, Hernandez AV, et al. Do margins matter? The influence of positive surgical margins on prostate cancer-specific mortality. European urology 2014; 65(4): 675-80.