interstitial brachytherapy with or without external-beam radiation therapy in treating patients with prostate cancer

Conditions: Prostate Cancer

Summary: rationale: radiation therapy uses high-energy x-rays and other sources to damage tumor cells. interstitial brachytherapy uses radioactive material placed directly into or near a tumor to kill tumor cells. combining interstitial brachytherapy with external-beam radiation therapy may kill more tumor cells. it is not yet known whether interstitial brachytherapy is more effective with or without external-beam radiation therapy in treating prostate cancer. purpose: randomized phase iii trial to compare the effectiveness of interstitial brachytherapy with or without external-beam radiation therapy in treating patients who have prostate cancer.

objectives: * compare the 5-year freedom from progression in patients with intermediate-risk prostate cancer treated with interstitial brachytherapy with or without external beam radiotherapy (ebrt). * compare biochemical (i.e., prostate-specific antigen) failure, biochemical failure by the phoenix definition, disease-specific survival, local progression, and distant metastases in patients treated with these regimens. * compare morbidity and quality of life of patients treated with these regimens. * determine the feasibility of collecting medicare data in a large radiation therapy oncology group (rtog) prostate cancer clinical trial for cost effectiveness and cost utility analysis of combined treatment with interstitial brachytherapy and ebrt. * prospectively collect diagnostic biopsy samples from these patients for future biomarker analyses. outline: this is a randomized, multicenter study. patients are stratified according to disease stage (t1c vs t2a or t2b), gleason score (≤ 6 vs 7), prostate-specific antigen (\< 10 ng/ml vs 10-20 ng/ml), and prior neoadjuvant hormonal therapy (yes vs no). patients are randomized to 1 of 2 treatment arms. * arm i: patients undergo external beam radiotherapy 5 days a week for 5 weeks. within 2-4 weeks of radiotherapy, patients undergo interstitial brachytherapy with iodine i 125 or palladium pd 103 seeds. * arm ii: patients undergo interstitial brachytherapy only, as in arm i. quality of life is assessed at baseline, at 4, 12, and 24 months, and then annually for 3 years. after completion of study treatment, patients are followed at 3-5 weeks, at 4, 6, 9, and 12 months, every 6 months for 4 years, and then annually thereafter.

Eligibility criteria:
disease characteristics: * histologically confirmed adenocarcinoma of the prostate * t1c-t2b, n0, m0 * intermediate-risk disease, as defined by 1 of the following: * gleason score \< 7 and prostate-specific antigen (psa) 10-20 ng/ml * gleason score 7 and psa \< 10 ng/ml * no evidence of distant metastases * prostate volume ≤ 60 cc by transrectal ultrasonography * american urological association voiding symptom score no greater than 15 (alpha blockers allowed) patient characteristics: age * 18 and over performance status * zubrod 0-1 life expectancy * not specified hematopoietic * not specified hepatic * not specified renal * not specified other * patients must use effective contraception * no other malignancy within the past 5 years except basal cell or squamous cell skin cancer or carcinoma in situ at any other site * no major medical or psychiatric illness that would preclude study therapy * no hip prosthesis prior concurrent therapy: biologic therapy * not specified chemotherapy * no prior chemotherapy endocrine therapy * prior neoadjuvant hormonal therapy allowed provided the following are true: * therapy was initiated within 2-6 months of study enrollment * therapy was no more than 6 months in duration * use of 5-alpha reductase inhibitors (e.g., finasteride) is discontinued before registration * no concurrent hormonal therapy radiotherapy * no prior pelvic radiotherapy surgery * no prior radical surgery for prostate cancer * no prior transurethral resection of the prostate * no prior cryosurgery other * no prior transurethral needle ablation of the prostate * no prior transurethral microwave thermotherapy of the prostate

Keywords: stage iib prostate cancer stage iia prostate cancer adenocarcinoma of the prostate