Gleason score predicts androgen independent progression after androgen deprivation therapy

Objective: The Gleason system is the most widely utilized histologic grading system for prostate cancer and a powerful predictor of cancer behavior. In this study, we evaluated the prognostic value of the Gleason grading system in predicting progression to androgen independent prostate cancer (AIPC). Methods: Records from 150 patients with advanced or metastatic prostate cancer treated with androgen deprivation therapy (ADT) were retrospectively reviewed. Androgen independent progression was defined as two consecutive elevations of serum prostate specific antigen (PSA) above the nadir value. Kaplan-Meier and the Cox proportional hazards methods were used to assess potential predictors of progression to AIPC. Results: Patients with low and moderate Gleason scores experienced significantly longer remissions compared to those with Gleason score of 8-10 (p=0.0006, Log-Rank test). The cumulative hazard of progressing to AIPC increased by almost 70% for each unit increase in total Gleason score. Conclusion: In this patient cohort the Gleason score was the only independent predictor of progression to AIPC.