High-dose rate iridium192 afterloading therapy in combination with external beam irradiation for localized prostate cancer.

Abstract

Development of afterloading techniques in combination with external radiotherapy allows for curative therapy modality for stage C prostate cancer. Between 10/92 and 12/95 128 patients were treated. Stage B and C tumors were found in 36 and 89 cases, respectively. All patients were pathologically proven to be node-negative by laparoscopic node dissection of the fossa obturatoria region. 9 Gy a week was applied during the first and second weeks of treatment (10/92-12/93: 10 Gy each week) interstitially with high-dose rate iridium192 brachytherapy to the prostate. After this, a four-field box of external beam radiation therapy was given to the prostate to a dose of 45 Gy/25 fractions (10/92-12/93: 40 Gy/20 fractions). Before starting treatment median PSA was 13.8 ng/ml. The median PSA 3, 12, and 24 months after completion of therapy was 1.2, 0.78, and 0.75 ng/ml, respectively. Negative biopsies 12 and 24 months after therapy were observed in 56% (49/87) and 72% (31/43), respectively.