Stratification of Contemporary Patients Undergoing Radical Prostatectomy for High-risk Prostate Cancer.

Abstract

Published data have shown heterogeneous outcomes for high-risk prostate cancer. Thus, we tried to identify more precise risk stratification system for contemporary high-risk prostate cancer.

Classifying patients according to National Comprehensive Cancer Network risk groups, we reviewed data of 1,905 men who underwent radical prostatectomy (RP) at our institution from 2006 to 2013. For our analyses, high-risk prostate cancers meeting at least one of two following factors were categorized as unfavorable high-risk prostate cancer: biopsy primary Gleason pattern 5 and/or multiple (a parts per thousand yen2) high-risk criteria present. All other men with high-risk prostate cancer were designated as having favorable high-risk disease. Postoperative outcomes, including biochemical recurrence-free survivals were assessed and compared via log-rank test and Cox proportional hazards model.

In multivariable analysis, primary Gleason 5 pattern on biopsy (p = 0.008) and multiple (a parts per thousand yen2) high-risk criteria (p < 0.001) were observed to be independent predictors of the risk of biochemical recurrence amongst high-risk group undergoing RP. Favorable high-risk prostate cancer group showed a significantly higher 5-year biochemical recurrence-free survival than unfavorable high-risk group (56.35 vs. 18.75 %; log-rank test: p < 0.001). Favorable high-risk group demonstrated significantly lower 5-year biochemical recurrence-free survival than intermediate-risk group (56.07 vs. 82.05 %; log-rank test: p < 0.001).

A significant heterogeneity existed in biochemical outcomes of contemporary patients with high-risk prostate cancer who underwent definitive RP. According to primary Gleason pattern and number of high-risk criteria present, high-risk group should be stratified further into favorable and unfavorable disease.