Outcome Predictors of Radical Prostatectomy Followed by Adjuvant Androgen Deprivation in Patients with Clinical High Risk Prostate Cancer and pT3 Surgical Margin Positive Disease

Abstract

Patients with high risk prostate cancer with pT3 tumor and positive surgical margins have a high risk of biochemical failure after radical prostatectomy and adjuvant androgen deprivation therapy. Predictors of cancer related death in this patient group are necessary. We performed subset analysis of a prospective trial including 550 consecutive patients with preoperative high risk prostate cancer (prostate specific antigen greater than 20 ng/ml ± cT3/4 ± biopsy Gleason 8-10). Men who underwent radical prostatectomy and received continuous adjuvant androgen deprivation therapy for pT3a/b N0-1 positive surgical margin disease were included in the analysis, and none of the patients received neoadjuvant androgen deprivation therapy or adjuvant radiation therapy. Overall 173 of 550 patients (31.5%) with a median followup of 67 months met the study inclusion criteria. For these men the estimated 8-year prostate cancer specific and overall survival rates were 86.3% and 77.0%, respectively. Tumor stage and positive surgical margin at the bladder neck were independent predictors of prostate cancer specific survival and overall survival, and were used to substratify cases. Those with pT3b disease with positive surgical margins at the bladder neck had the highest risk of death (5-year cancer specific survival 60.0% and overall survival 52.3%), while pT3a disease (regardless of positive surgical margin location and lymph node invasion) and pT3b tumors with negative bladder neck margins had 8-year prostate cancer specific survival and overall survival rates of 92.0% and 84.9%, respectively. The results of this trial demonstrated the heterogeneity of high risk prostate cancer cases with T3 tumors and positive surgical margins. The presented substratification by tumor stage and positive surgical margin location identifies men at high risk for prostate cancer related death and might help in the design of adjuvant therapy trials.