PURPOSE: A positive surgical margin (SM) during radical prostatectomy (RP) increases risk of biochemical recurrence.
We evaluated the effect of nerve-sparing procedures on risk of positive SM for pT2- and pT3-category tumors. We hypothesized that nerve sparing would increase rates of pT2 positive margins.
METHODS: We evaluated a historical cohort of 9,915 consecutive RP patients treated at The Ottawa Hospital or Memorial Sloan-Kettering Cancer Center from 2000 to 2010. Patients underwent open, laparoscopic, or robotic RP. The primary outcome was presence of a positive SM stratified by pathologic pT2 and pT3 categories. The association between nerve sparing and positive margin was adjusted for prostate-specific antigen, RP Gleason sum, surgical modality, surgical date, and location in the multivariable model.
RESULTS: Of 6,120 eligible patients, 3,958 (64.7%) had open RP, 1,566 (25.6%) had laparoscopic RP, and 596 (9.7%) had robotic RP. Approximately 8.6% (363/4,199) of patients with pT2-category disease and 25.2% (485/1,921) of patients with pT3-category disease had a positive margin. Patients with pT2-category disease who underwent a bilateral nerve-sparing procedure were more likely to have a positive margin when compared with those who underwent nerve resection on multivariable analysis (relative risk [RR] = 1.52, 95% CI: 0.97-2.39) after adjusting for confounders. Patients with pT3-category disease who underwent a bilateral nerve-sparing procedure had no associated increase in risk of positive margin after adjustment for other variables (RR = 0.96, 95% CI: 0.80-1.16). Prostate incision into tumor (pT2R1) was significantly more likely in patients treated with robotic surgery (RR = 1.76, 95% CI: 1.25-2.48) than in those with open surgery. There was no difference between laparoscopic and open RP (RR = 0.86, 95% CI: 0.65-1.12).
CONCLUSIONS: Bilateral nerve sparing is associated with increased risk of positive SMs in patients with pathologic T2-category disease during RP.
Preston MA, Breau RH, Lantz AG, Morash C, Gerridzen RG, Doucette S, Mallick R, Eastham JA, Cagiannos I. Are you the author?
Department of Urology, Brigham and Women's Hospital, Boston, MA; Department of Surgery, The Ottawa Hospital, General Campus, University of Ottawa, Ottawa, Ontario, Canada; Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Department of Urology, Dalhousie University, Halifax, Nova Scotia, Canada; Research Methods Unit, Capital Health Authority, Halifax, Nova Scotia, Canada; Department of Urology, Urology Service, Memorial Sloan-Kettering Cancer Center, New York, NY.
Reference: Urol Oncol. 2014 Oct 9. pii: S1078-1439(14)00317-2.