Risk factors for PSA relapse after radical prostatectomy in organ confined prostate cancer

Abstract

Introduction & objectives: To determine risk factors, time and identify patient’s group that are at highest risk for PSA relapse after radical prostatectomy (RP) in organ confined prostate cancer (PCa). Material & methods: Patients who underwent RP at our institution between 2003 and 2011 with confirmed organ confined (pT2N0-x) PCa, available follow up data more than 36 month after surgery and without any adjuvant treatment were included into the study. Age, pre operative PSA, Gleason score (GL), surgical margin status (R0/1) were analyzed according time to PSA relapse (>0.2 ng/ml) or last follow up date without relapse. Patients were stratified according detected the most significant risk factors and patients groups were identified for highest risk of PSA relapse. Cox regression, Kaplan-Meier and logistic regression methods were used for statistical analysis. Results: 488 patients fulfilled inclusion criteria. Median follow up was 61 (range 1-134) months. Median patient’s age was 65 (43-77) years and pre operative PSA – 6.02 (0.44-78) ng/ml. Positive surgical margins (R1) rate was 26.8%, pathological stage pT2a was detected in 10.9%, pT2b in 4.5 and pT2c in 84.6% of cases. GL 6 was founded in 53.6%, GL 7(3+4) in 40.4, GL 7(4+3) in 2.5 and GL ≥8 in 3.5% of patients. PSA relapse was detected in 17.4% and median time to relapse was 15 (1-110) months. 79.1% of relapse cases occurred within 3 years after surgery. Cox regression analysis shows that GL (p<0.0001, HR 1.7), R status (p<0.0001, HR 0.307) and PSA (p<0.0001, HR 1.076) are significant risk factors for biochemical relapse. Kaplan-Meier analysis revealed that for all study patients calculated 10-year PSA relapse free survival is 72.3%. 5-year PSA relapse free survival for patients with R0 vs. R1 was 90.4% and 62.8%; for GL 6 – 89%, for GL 7(3+4) – 80.2%, for GL 7(3+4) – 57.1% and for GL ≥8 – 52.9%. Not significant difference was only comparing G