Evaluating the Impact of Prostate Only Versus Pelvic Radiation for N+ Prostate Cancer.

In an era with increasing evidence in favour of an aggressive local treatment, where an extended pelvic lymph node dissection (EPLND) is more frequently performed and with data supporting the potential role for external beam radiotherapy (EBRT) in pelvic node positive (N1) prostate cancer (PC), the treatment of N1 PC patients needs to be revised. Seen the lack of clear guidelines regarding the extent of radiation field in N1 prostate cancer patients, there is an urgent need for studies evaluating the place of pelvic EBRT. The aim of this trial is thus to evaluate if pelvic irradiation has an impact on clinical relapse free survival in pathological N1 PC. The hypothesis is that performing a pelvic EBRT after EPLND in pathological N1 PC patients results in a significant improved clinical relapse free survival with 15% when compared to prostate only EBRT. This will be evaluated in a multicentre Phase III stratified randomised trial randomising patients with PC and 1-4 positive lymph nodes on EPLND between prostate(bed) only radiotherapy + 2 years of ADT or pelvic radiotherapy + 2 years of androgen deprivation. A total of 330 patients will be enrolled in this trial. Stratification is based on the number of positive lymph nodes since patients with increased number of positive lymph nodes exhibit a poorer prognosis.