Interstitial Brachytherapy With or Without External-Beam Radiation Therapy in Treating Patients With Prostate Cancer
Condition: Prostate Cancer
MeSH terms: Prostatic Neoplasms
Study type: Interventional
Phase: Phase 3

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.
    

Detailed description: 
      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.
    

Intervention name(s): Brachytherapy (100/110); Brachytherapy (125/145); External Beam Radiation Therapy
Intervention type(s): Radiation; Radiation; Radiation
Intervention description(s): 100 Gy Palladium-103 (P-102) or 110 Gy Iodine-125 (I-125) seeds within 2-4 weeks of completion of external beam radiotherapy.; 125 Gy Palladium-103 (P-103) or 145 Gy Iodine-125 (I-125) seeds within 4 weeks of study entry.; Total dose of 45 Gy to the prostate and seminal vesicles as a daily dose of 1.8 Gy given 5 times per week. The prescribed dose is defined at the International Commission of Radiation Units and Measurements (ICRU) reference point. Both 3D-conformal radiation therapy (3DCRT) and intensity modulated radiation therapy (IMRT) are permitted.
Other intervention name(s): EBRT
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: stage IIB prostate cancer; stage IIA prostate cancer; adenocarcinoma of the prostate