Biochemical failure in men following radical retropubic prostatectomy: Impact of surgical margin status and location

Purpose: The significance of isolated positive apical surgical margins in radical retropubic prostatectomy (RRP) specimens remains controversial. We examine the effects of margin status and location on biochemical recurrence rates in patients undergoing RRP. Materials and Methods: Of 800 patients with RRP we identified 498 without pathological evidence of lymph node, seminal vesicle or adjacent organ involvement and with at least 6 months of followup. Patients were subdivided into apex only positive (AM+), nonapical isolated positive (OM+), multiple positive (MM+) and negative (SM-) surgical margins. The rate and interval to biochemical disease recurrence were determined in each group. Univariate and multivariate analysis as well as Kaplan-Meier curves were used to test differences among these groups. Results: Of the 498 men who met our inclusion criteria 400 were SM-, 28 were AM+, 57 were OM+ and 13 were MM+ at a median followup of 49, 59, 64 and 83 months, respectively. Biochemical recurrence rates for SM-, AM+, OM+ and MM+ were 9.3%, 21.4%, 26.3% and 30.8%, respectively. Median time to biochemical failure in the SM-, AM+, OM+ and MM+ groups was 34, 19.5, 46.0 and 6.8 months, respectively. Biochemical recurrence was not statistically different among the AM+, OM+ and MM+ groups. On univariate analysis AM+, OM+ and MM+ were significant predictors of recurrence (p < 0.05, < 0.005, and <0.05, respectively). On multivariate models only pretreatment prostate specific antigen and OM+ were independent predictors of biochemical recurrence. Conclusions: A positive surgical margin conveys increased risk for biochemical recurrence. Patients with AM+ experienced biochemical recurrence more frequently and rapidly than those with SM-. AM+ conveys a similar risk of recurrence compared with OM+ and MM+. Apical margin status did not independently predict biochemical recurrence.