Postprostatectomy radiotherapy for high-risk prostate cancer

Abstract

Objectives. To assess the biochemical and clinical results of postprostatectomy radiotherapy (RT) for high-risk, mostly non-rgan-confined prostate cancer. Methods. After radical prostatectomy, 66 consecutive patients received either adjuvant (n = 29) or therapeutic (n = 37) postoperative RT. Therapeutic RT was given for persistently elevated postoperative prostate-specific antigen (PSA) levels (n = 14), gradually rising PSA levels (n = 6), or clinical local recurrence (n = 17). The selection of time and referral for RT was at the discretion of the treating urologists. Results. The mean and median follow-up after surgery was 56.8 and 54.2 months, and after radiotherapy, it was 43.2 and 35.0 months, respectively. At 5 years, the actuarial biochemical control for the whole collective was 59.7% (95% confidence interval [CI] 43.3% to 72.8%). Patients treated with adjuvant RT had statistically improved biochemical control (85.2% versus 34.0%, P = 0.001), but not disease-free survival (91% versus 73%, P = 0.09). Advanced tumor stage (pT3b-4) (relative risk 16.6; 95% CI 0.9 to 313.3; P = 0.01), poorly differentiated histologic features (relative risk 4.63; 95% CI 1.8 to 12.2; P = 0.001), and pre-RT PSA (relative risk 1.15, 95% CI 1.06 to 1.25; P = 0.003) were associated with a statistically significant increased risk of biochemical failure. Conclusions. Although adjuvant postoperative RT resulted in improved biochemical control, no significant difference in disease-free survival has been obtained to date. It therefore remains to be determined whether the better biochemical control observed will ultimately translate into a survival benefit after longer follow-up and prospective trials.