Non-apical positive surgical margins after radical prostatectomy for pT2 prostate cancer is associated with the highest risk of recurrence.

BACKGROUND AND OBJECTIVE To investigate how location of positive surgical margins (PSM) in pT2 tumors affect the risk of biochemical recurrence (BR). METHODS The study includes 1,133 consecutive patients from 1995 until end of 2011, who had organ-confined disease (pT2) following RP. The location of PSM was stratified into apical and non-apical. BR was defined as the first PSA ≥ 0.2 ng/ml after RP. Risk of BR was analyzed with Kaplan-Meier and Cox regression analysis. RESULTS Median follow-up was 3.6 years (range: 0.5-15.5 years). The overall pT2 PSM rate was 26.3%. Overall, a pT2 with PSM had a 3.1-fold increased risk of BR compared to margin negative patients. Patients with pT2 apical and non-apical PSM had a 5-year biochemical recurrence-free survival of 84.9% (95% CI: 77.6-92.2%) and 78.6% (95% CI: 71.3-85.9%), respectively. In multivariate analysis, pT2 apical and non-apical PSM was individually associated with a 2.2- and 3.8-fold increased risk of BR compared to margin negative patients. CONCLUSION In our cohort the location of pT2 PSM was associated with time to BR, that is, patients with non-apical pT2 PSM endured the highest risk of BR compared to apical PSM. This may indicate that not all patients with pT2 PSM should be offered adjuvant therapy.