Dosimetric Predictors of Toxicity in Patients With Early-Stage Prostate Cancer Treated With Moderately Hypofractionated IMRT or PBT: A Multi-Institutional Analysis

In this multi-institutional analysis of 1139 early-stage PC patients treated with moderately hypofractionated IMRT or PBT, risk of serious late GU and GI complications was low for both treatment groups. Analysis of the dosimetric variables identified an association of Grade 3+ GU toxicity with low-dose radiation exposure of the bladder. Grade 3+ GI toxicity was unrelated to dosimetric variables. PBT plans yielded less exposure of non-target organs to lower-dose radiation while IMRT plans yielded less exposure of non-target organs to higher-dose radiation.