High-dose-rate brachytherapy alone given as two or one fraction to patients for locally advanced prostate cancer: acute toxicity.

Abstract

To evaluate early urinary (GU) and gastrointestinal (GI) adverse events (AEs) after two or one fraction of high-dose rate brachytherapy (HDR-BT) in advanced prostate cancer. 165 patients were treated with 2 × 13 Gy (n=115), or a single dose of 19 Gy (n=24) or 20 Gy (n=26) HDR-BT. Early AEs were assessed using the RTOG scoring system and the International Prostate Symptom Score (IPSS). Week-2 prevalence of severe IPSS symptoms was higher after 20 Gy than after 26 or 19 Gy but by 12 weeks all groups were at pre-treatment levels or less. Grade-3 GU toxicity was observed ≤9% of patients. No Grade 4 GU and no Grade 3 or 4 GI complications were observed. However, there was a significant increase in catheter use in the first 12 weeks after implant after 19 and 20 Gy compared with 2 × 13 Gy. Single dose HDR-BT is feasible with acceptable levels of acute complications; tolerance may have been reached with the single 19 Gy schedule.