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.

Eligibility Criteria:
DISEASE CHARACTERISTICS:

* Histologically confirmed adenocarcinoma of the prostate within the past 6 months

  * Clinical stage T1-2c
* Combined Gleason score 2-6
* Prostate-specific antigen (PSA) \< 10 ng/mL within the past 6 months

  * PSA evaluated at least 10 days after prostate biopsy
  * For patients who received finasteride, PSA evaluated at least 30 after completion of finasteride
  * For patients who received dutasteride, PSA evaluated at least 90 after completion of dutasteride
* No regional lymph node involvement
* No distant metastases

PATIENT CHARACTERISTICS:

* Zubrod performance status 0-1
* No unstable angina and/or congestive heart failure requiring hospitalization within the past 6 months
* No transmural myocardial infarction within the past 6 months
* No acute bacterial or fungal infection requiring IV antibiotics
* No chronic obstructive pulmonary disease exacerbation or other respiratory illness requiring hospitalization or precluding study treatment
* No hepatic insufficiency resulting in clinical jaundice and/or coagulation defects
* No known AIDS
* No prior or concurrent lymphomatous/hematogenous malignancy or other invasive malignancy except nonmelanomatous skin cancer or any other cancer for which the patient has been continually disease-free for ≥ 5 years (e.g., carcinoma in situ of the bladder or oral cavity)
* No other severe, active comorbidity

PRIOR CONCURRENT THERAPY:

* See Disease Characteristics
* No prior radical prostatectomy or cryosurgery for prostate cancer
* No prior hormonal therapy, including any of the following:

  * Luteinizing hormone-releasing hormone agonists (e.g., goserelin or leuprolide)
  * Antiandrogens (e.g., flutamide or bicalutamide)
  * Estrogens \[e.g., diethylstilbestrol (DES)\]
  * Surgical castration (bilateral orchiectomy)
* No prior pelvic radiotherapy or prostate brachytherapy
* No prior or concurrent cytotoxic chemotherapy for prostate cancer
* At least 30 days since prior finasteride
* At least 90 days since prior dutasteride
* No concurrent neoadjuvant or adjuvant hormonal therapy
* Concurrent warfarin or other blood-thinning agents allowed