Acceptance and efficacy of recommended adjuvant radiotherapy in patients with positive lymph nodes at radical prostatectomy: a preference-based study.

PURPOSE: To investigate acceptance and efficacy of recommended adjuvant radiotherapy in patients with positive lymph nodes at radical prostatectomy. METHODS: Among 495 patients with positive lymph nodes who consecutively underwent radical prostatectomy between 2007 and 2017, we investigated 347 patients who were recommended to undergo adjuvant radiotherapy by a multidisciplinary post-therapeutic tumor board and in whom information whether such treatment was eventually given was available. The median follow-up for censored patients was 5.4 years. Univariate analyses were performed using Kaplan-Meier curves, Mantel-Haenszel hazard ratios and log rank tests. Proportional hazard models for competing risks were used for multivariable analyses. RESULTS: Adjuvant radiotherapy was independently associated with lower overall mortality and in high-risk patients (Gleason score 8-10 or three or more involved lymph nodes) also with lower prostate cancer-specific mortality. In patients with a Gleason score of 8-10 or three or more involved lymph nodes, the hazard ratio for adjuvant radiotherapy was 0.455 (95% confidence interval 0.257-0.806, p = 0.0069) for overall and 0.426 (95% confidence interval 0.201-0.902, p = 0.0259) for prostate cancer-specific mortality. Among patients receiving adjuvant radiotherapy, there was a trend to lower mortality when such treatment was combined with adjuvant androgen deprivation. CONCLUSION: Adjuvant radiotherapy decreased mortality in patients with positive lymph nodes at radical prostatectomy with further disease factors but not in patients with low-risk disease. Simultaneous androgen deprivation might increase efficacy. Multidisciplinary recommendations may possibly increase the use of adjuvant radiotherapy in this setting.