As there is no prospective data on the combination of abiraterone acetate plus prednisone and salvage prostate bed radiotherapy, the aim of this study was to further evaluate the safety profile of abiraterone acetate plus prednisone in patients with prostate cancer who are biochemically relapsing after surgery and undergo salvage radiotherapy with 6-months LH-RH agonist. This evidence concerns the gene GNRH1 and prostate carcinoma.