Recent large, prospective, randomised studies have demonstrated that adjuvant radiotherapy (RT) is a safe and effective procedure for preventing disease recurrence in locally advanced prostate cancer (PCa) patients. However, no study has ever tested the role of adjuvant RT in node-positive patients after radical prostatectomy (RP).

We hypothesised that adjuvant RT with early hormone therapy (HT) might improve long-term outcomes of patients with PCa and nodal metastases treated with RP and extended pelvic lymph node dissection (ePLND).

This retrospective study included 250 consecutive patients with pathologic lymph node invasion. We assessed factors predicting long-term biochemical recurrence (BCR)-free and cancer-specific survival (CSS) in node-positive PCa patients treated with RP, ePLND, and adjuvant treatments between 1988 and 2002 in a tertiary academic centre.

All patients received adjuvant treatments according to the treating physician after detailed patient information: 129 patients (51.6%) were treated with a combination of RT and HT, while 121 patients (48.4%) received adjuvant HT alone.

BCR-free survival and CSS in patients with node-positive PCa.

Mean follow-up was 95.9 mo (median: 91.2). BCR-free survival and CSS rates at 5, 8, and 10 yr were 72%, 61%, 53% and 89%, 83%, 80%, respectively. In multivariable Cox regression models, adjuvant RT and the number of positive nodes were independent predictors of BCR-free survival (p=0.002 and p=0.003, respectively) as well as of CSS (p=0.009 and p=0.01, respectively). Moreover, there was significant gain in predictive accuracy when adjuvant RT was included in multivariable models predicting BCR-free survival and CSS (gain: 3.3% and 3%, respectively; all p<0.001).

Our data showed excellent long-term outcome for node-positive PCa patients treated with radical surgery plus adjuvant treatments. This study is the first to report a significant protective role for adjuvant RT in BCR-free survival and CSS of node-positive patients.