Comparison of the 5-year outcome and morbidity of three-dimensional conformal radiotherapy versus transperineal permanent iodine-125 implantation for early-stage prostatic cancer.

PURPOSE: To compare the prostate-specific antigen (PSA) relapse-free survival outcome and incidence of late toxicity for patients with early-stage prostate cancer treated at a single institution with either three-dimensional conformal radiotherapy (3D-CRT) or transperineal permanent implantation (TPI) with iodine-125 seeds. MATERIALS AND METHODS: Patients with favorable-risk prostate cancer, defined as a pretreatment PSA of less than or equal to 10.0 ng/mL, Gleason score of 6 or lower, and stage less than or equal to T2b, were selected for this analysis. Between 1989 and 1996, 137 such patients were treated with 3D-CRT and 145 with TPI. The median ages of the 3D-CRT and TPI groups were 68 years and 64 years, respectively. The median dose of 3D-CRT was 70.2 Gy, and the median implant dose was 150 Gy. Prostate-specific antigen relapse was defined according to the American Society of Therapeutic Radiation Oncology Consensus Statement, and toxicity was graded according to the Radiation Therapy Oncology Group ...