Subclassification of high-risk clinically organ-confined prostate cancer for early cancer-specific mortality after radical prostatectomy.

OBJECTIVE High-risk clinically localized prostate cancer is seen in a highly heterogeneous population with a wide variation of clinical aggressiveness and a novel subclassification for the better prediction of clinical outcomes is needed. The aim of this study is to validate a modified D'Amico risk criteria for substratification of high-risk prostate cancer with regard to the prediction of biochemical recurrence, clinical progression-free survival or prostate cancer-specific mortality after radical prostatectomy. METHODS We conducted a retrospective multicenter cohort study including 461 clinically organ-confined (cT1-2), D'Amico high-risk prostate cancer patients who underwent radical prostatectomy with pelvic lymph node dissection. The modified criteria subclassified D'Amico high-risk patients into high-risk (n = 189, single high-risk parameter and two low-risk parameters) and very high-risk (n = 272, at least one more intermediate or high-risk parameter in addition to the qualifying high-risk parameter) groups. Biochemical recurrence-free survival, clinical progression-free survival, prostate cancer-specific mortality and overall survival were analyzed. RESULTS The very high-risk group, compared with high-risk group, had significantly poorer biochemical recurrence (5- and 10-year biochemical recurrence-free rates: 52.8 vs 73.9% and 42.1 vs 61.7%, respectively, P < 0.0001), clinical progression-free survival (5- and 10-year survivals: 91.8 vs 98.2% and 80.5 vs 98.2%, respectively, P = 0.0013) and prostate cancer-specific mortality (5- and 10-year mortalities: 2.5 vs 0.0% and 6.7 vs 0.0%, respectively, P = 0.0124). CONCLUSION D'Amico high-risk patients can achieve very favorable outcomes unless they are classified as very high risk. Our novel subclassification method is very simple and useful for better patient counseling and decision-making in the pretreatment setting.