Location of Positive Surgical Margin and Its Association With Biochemical Recurrence Rate Do Not Differ Significantly in Four Different Types of Radical Prostatectomy

PURPOSE To analyze the location of the positive surgical margin (PSM) and its association with the biochemical recurrence (BCR) rate in cases of radical prostatectomy (RP) according to the type of surgery. MATERIALS AND METHODS We retrospectively analyzed 1,880 cases of RP. Baseline characteristics were analyzed. Locations of the PSM were recorded in the four surgery groups as apex, anterior, posterolateral, and base and were analyzed by using chi-square test. The association of the location of the PSM with the BCR rate was analyzed by using Kaplan-Meier survival analysis according to the type of surgery, which included radical perineal prostatectomy (RPP, n=633), radical retroperitoneal prostatectomy (RRP, n=309), laparoscopic radical prostatectomy (LRP, n=164), and robot-assisted laparoscopic radical prostatectomy (RALRP, n=774). RESULTS A PSM was found in a total of 336 cases (18%): 122 cases of RPP (18%), 67 cases of RRP (17%), 29 cases of LRP (17%), and 119 cases of RALRP (15%). The PSM rate did not differ significantly by surgical type (p=0.142). The location of the PSM was the apex in 136 cases (7.2%), anterior in 67 cases (3.5%), posterolateral in 139 cases (7.3%), and base in 95 cases (5.0%), and showed no significant difference according to surgical type (p=0.536, p=0.557, p=0.062, and p=0.109, respectively). The BCR rate according to the location of the PSM did not differ significantly for the four types of surgery (p=0.694, p=0.301, p=0.445, and p=0.309 for RPP, RRP, LRP, and RALRP, respectively). CONCLUSIONS The location of the PSM seemed to be unrelated to type of RP. There was no significant correlation between the BCR rate and the location of the PSM for any of the RP types.