High Versus Low Dose Supplemental External Radiation With Pd-103 for Prostate Cancer

The objective of this study is test the hypothesis that delivering a higher percentage of the radiation dose as external radiation versus implant will lead to higher tumor control rates.

Research design A total of 600 patients with AJC clinical stage T1-T2 prostatic carcinoma (Gleason grade 7 to 10 and/or PSA 10 to 20 ng/ml) will be randomized to treatment with 44 Gy versus 20 Gy external radiation plus a Pd-103 implant boost (90 Gy versus 105 Gy, respectively).

Methodology: Patients will be randomized by the method of random permuted blocks.

Cancer status will be monitored by serial serum PSA at 6, 12, 18 and 24 months and yearly thereafter. Treatment-related morbidity will be monitored by personal interview, using standard American Urologic Association and Radiation Therapy Oncology Group criteria at 1, 3, 6, 12 and 24 months. The primary endpoint will be based on serum PSA. A value above 1.0 ng/ml two years after treatment will be considered to have residual or recurrent cancer and to have failed therapy.

Findings: 566 patients have been randomized and the study was closed due to slowing accrual. A preliminary analysis shows similar morbidity between the treatment arms, and nearly identical cancer control rates between randomization arms.