Adjuvant radiotherapy in patients with node-positive prostate cancer after radical prostatectomy

Purpose Our study was to determine whether immediate androgen deprivation therapy (ADT) plus radiotherapy (RT) extends survival in men with node-positive prostate cancer (PCa) after radical prostatectomy (RP) compared with those who received ADT alone. Methods A total of 99 consecutive patients with pathological positive lymph nodes (pN1) PCa were included in this study to receive immediate ADT plus RT (n = 70) or to receive immediate ADT alone (n = 29). The primary endpoint was castration-resistant prostate cancer (CRPC) free survival; the secondary endpoints were distant metastasis-free survival. Cox regression was used to assess the independent risk factors for CRPC. Results The median follow-up time was 34.0 (24.8, 47.8) months and 34.25 (23.0, 49.0) months, respectively, in the ADT + RT group and ADT-alone group. The 5-year CRPC-free survival rate was 79.5% and 58.3%, respectively, in the ADT + RT group and ADT-alone group (p = 0.308). The 5-year distant metastasis-free survival rate was 71.4% and 38.8, respectively, in the ADT + RT group and ADT-alone group (p = 0.478). Compared with ADT-alone group, we saw a modest, but no significant improvement in CRPC-free survival and distant metastasis-free survival in ADT + RT group. The results of Cox regression showed that positive lymph nodes >= 4 was an independent risk factor for CRPC (p = 0.041). Conclusions We found that immediate ADT plus RT compared to ADT alone did not improve CRPC-free and metastasis-free survival. Multivariate Cox regression analyses also indicated that patients with positive lymph nodes < 4 may benefits from ADT plus RT.

Automated summary

The purpose of this study was to determine whether immediate androgen deprivation therapy (ADT) plus radiotherapy (RT) extends survival in men with node-positive prostate cancer after radical prostatectomy compared with those who received ADT alone. The results showed that the addition of RT to ADT did not significantly improve castration-resistant prostate cancer (CRPC)-free and distant metastasis-free survival. However, patients with positive lymph nodes < 4 may benefit from ADT plus RT.