Radiation Therapy in Treating Patients With Stage II Prostate Cancer

RATIONALE: Giving radiation therapy that uses a 3-dimensional (3-D) image of the tumor to help focus thin beams of radiation directly on the tumor, and giving hypofractionated radiation therapy (higher doses over a shorter period of time), may be less costly with fewer side effects and just as effective in treating prostate cancer. PURPOSE: This randomized phase III trial is studying several different radiation therapy regimens to compare how well they work in treating patients with stage II prostate cancer.

OBJECTIVES: Primary * Compare the disease-free survival (DFS) of patients with favorable-risk stage II prostate cancer treated with hypofractionated vs conventionally fractionated three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiotherapy (IMRT). Secondary * Compare time to local progression, freedom from biochemical recurrence, and disease-specific and overall survival of patients treated with these regimens. * Determine the incidence of gastrointestinal and genitourinary toxic effects in patients treated with these regimens. * Compare the degree, duration, and significant differences in disease-specific health-related quality of life (HRQOL) decrements, using the Expanded Prostate Cancer Index Composite (EPIC), in patients treated with these regimens. * Determine whether anxiety and/or depression, as measured by the Hopkins Symptom Checklist-25 (HSCL-25), are decreased with therapy that improves DFS of these patients . * Determine whether the incremental gain in DFS outweighs decrements in the generic domains of HRQOL (i.e., mobility, self care, usual activities, pain/discomfort, and anxiety/depression) in patients treated with these regimens. * Conduct a cost-utility analysis of hypofractionated 3D-CRT or IMRT as a prostate cancer therapy if this regimen is shown to be as effective as conventionally fractionated 3D-CRT or IMRT in improving DFS. OUTLINE: This is a randomized, controlled, multicenter study. Patients are stratified according to Gleason score (2-4 vs 5-6), prostate-specific antigen (PSA) level (\< 4 ng/mL vs 4-\<9 ng/mL), and planned radiotherapy modality (three-dimensional conformal radiotherapy \[3D-CRT\] vs intensity-modulated radiotherapy \[IMRT\]). Patients are randomized to 1 of 2 treatment arms. * Arm I: Patients undergo conventionally fractionated 3D-CRT or IMRT once daily 5 days a week for 8.2 weeks (total of 41 treatments). * Arm II: Patients undergo hypofractionated 3D-CRT or IMRT once daily 5 days a week for 5.6 weeks (total of 28 treatments). Quality of life, anxiety, and depression are assessed at baseline and then at 6 months and 1, 2, and 5 years after the start of radiotherapy. After completion of study treatment, patients are followed every 3 months for 2 years, every 6 months for 3 years, and then annually thereafter. PROJECTED ACCRUAL: A total of 1,067 patients will be accrued to this study.