The study was comprised of 17,913 men with a median age of 64 years with pT2-4N1M0 prostate cancer (PC) consecutively treated between 1995 and 2017, with postradical prostatectomy (RP) and pelvic lymph node (LN) assessment. The patients were then followed for possible treatment with adjuvant radiation therapy (aRT) or early salvage radiation therapy (sRT). It was determined that men with pN1 PC and 4 or more as compared with 1-3 positive pelvic LNs appear to benefit the most from the use of aRT.