Radical prostatectomy vs. intensity-modulated radiation therapy in the management of localized prostate adenocarcinoma.

Abstract

To determine whether radical prostatectomy (RP) or intensity-modulated radiation therapy (IMRT) to > or =72 Gy, plus hormonal therapy if indicated, results in improved biochemical disease-free survival (BDFS) in localized prostate adenocarcinoma. Between 1997 and 2005, a consecutive sample of 556 patients who underwent RP (n=204) or IMRT (n=352) at two referral centers was analyzed. The patients were stratified into prognostic groups based on clinical stage, Gleason score, and pretreatment prostate-specific antigen (PSA). The outcome measure was BDFS. IMRT patients had more advanced disease at baseline (p<.001). There was no difference in five-year BDFS rates between RP and IMRT in the favorable (92.8% vs. 85.3%, p=.20) or intermediate prognosis (86.7% vs. 82.2%, p=.46) subsets. A difference favoring IMRT plus hormonal therapy was seen in the poor prognosis (38.4% vs. 62.2%, p<.001) subset. Within the entire cohort, after adjustment for confounding variables, Gleason score (p<.001) and clinical stage (p<.001) predicted BDFS, but treatment modality (p=.06) did not. Within the poor prognosis subset, treatment modality (p=.006) predicted BDFS. BDFS is similar between RP and IMRT for patients with a favorable or intermediate prognosis. Patients with a poor prognosis display higher BDFS when treated with IMRT to > or =72 Gy plus hormonal therapy.