Radiation Therapy in Treating Patients With Stage II or Stage III Prostate Cancer

RATIONALE: Radiation therapy uses high-energy x-rays and other sources to damage tumor cells. Internal radiation therapy uses radioactive material placed directly into or near a tumor to kill tumor cells. Giving radiation therapy in different ways may kill more tumor cells.

PURPOSE: This phase II trial is studying how well giving internal radiation therapy together with external-beam radiation therapy works in treating patients with stage II or stage III prostate cancer.

OBJECTIVES:

Primary

* Determine the rate of late grade 3 or greater genitourinary and gastrointestinal toxicity after treatment with external beam radiotherapy and high-dose rate brachytherapy in patients with stage II or III adenocarcinoma of the prostate.

Secondary

* Determine acute grade 3 or greater genitourinary and gastrointestinal toxicity in patients treated with this regimen.
* Determine freedom from biochemical failure in patients treated with this regimen.
* Determine overall survival of patients treated with this regimen.
* Determine disease-specific survival of patients treated with this regimen.
* Determine clinical relapse (local and/or distant) in patients treated with this regimen.
* Develop a quality assurance process for high-dose rate prostate brachytherapy.

OUTLINE: This is a multicenter study. Patients are stratified according to prostate-specific antigen (≤ 10 ng/mL vs 11-20 ng/mL), T stage (T1c-T2c vs T3a-T3b), combined Gleason score (2-6 vs 7 vs 8-10), prior hormonal therapy (no vs yes), and timing of high-dose rate brachytherapy (before external beam radiotherapy vs after external beam radiotherapy).

Patients are followed at 3, 7, 9, and 12 months, every 6 months for 5 years, and then annually thereafter.

Eligibility Criteria:
Inclusion Criteria:

1. Histologically confirmed, adenocarcinoma of the prostate, clinical stage T1c-T3b, N0, M0.
2. Patient will have clinically negative nodes as established by imaging (pelvic computed tomography (CT), magnetic resonance imaging (MRI)).
3. The patient will be clinically M0.
4. Zubrod status 0-1.
5. No prior pelvic or prostate radiation or chemotherapy for prostate cancer; induction hormonal therapy beginning ≤ 120 days prior to registration is acceptable.
6. One of the following combinations of factors:

   Clinical stage T1c-T2c, Gleason score 2-6 and prostate-specific antigen (PSA) \>10 but ≤ 20 Clinical stage T3a-T3b, Gleason score 2-6 and PSA ≤ 20 Clinical stage T1c-T3b, Gleason score 7-10 and PSA ≤ 20
7. Patients must sign a study-specific consent form prior to registration.

Exclusion Criteria:

1. Stage T4 disease.
2. Lymph node involvement (N1).
3. Evidence of distant metastases (M1).
4. Radical surgery for carcinoma of the prostate.
5. Previous hormonal therapy beginning \> 120 days prior to registration.
6. Major medical or psychiatric illness which, in the investigator's opinion, would prevent completion of treatment and would interfere with follow-up.
7. Prior transurethral resection of the prostate (TURP).
8. Prior invasive malignancy(except non-melanomatous skin cancer) unless disease free for a minimum of 3 years (For example, carcinoma in situ of the oral cavity or bladder are permissible).
9. Hip prosthesis.