Prostate cancer: stratifying intermediate-risk patients for radiotherapy

Prostate-specific antigen density predicts favorable pathology and biochemical recurrence in patients with intermediate-risk prostate cancer

This study was designed to identify clinical predictors of favorable pathology and biochemical recurrence (BCR) in patients with intermediate-risk prostate cancer (IRPCa). Between 2006 and 2012, clinicopathological and oncological data from 203 consecutive men undergoing robot-assisted radical prostatectomy (RARP) for IRPCa were reviewed in a single-institutional retrospective study. Favorable pathology was defined as Gleason score ≤6 and organ-confined cancer as detected by surgical pathology. Logistic regression analysis was used to determine predictive variables of favorable pathology, and the Kaplan–Meier and multivariate Cox regression model were used to estimate BCR-free survival after RARP. Overall, 38 patients (18.7%) had favorable pathology after RARP. Lower quartile prostate-specific antigen density (PSAD) was associated with favorable pathology compared to the highest quartile PSAD after adjusting for preoperative PSA, clinical stage and biopsy Gleason score (odds ratio, 5.42; 95% confidence interval, 1.01–28.97; P = 0.048). During a median 37.8 (interquartile range, 24.6–60.2) months of follow-up, 66 patients experienced BCR. There were significant differences with regard to BCR free survival by PSAD quartiles (log rank, P = 0.003). Using a multivariable Cox proportion hazard model, PSAD was found to be an independent predictor of BCR in patients with IRPCa after RARP (hazard ratio, 4.641; 95% confidence interval, 1.109–19.417; P = 0.036). The incorporation of the PSAD into risk assessments might provide additional prognostic information and identify some patients in whom active surveillance would be appropriate in patients with IRPCa.