A case-matched cohort analysis study compared acute and late genitourinary (GU) and gastrointestinal (GI) toxicity outcomes in patients with prostate cancer (PC) who received treatment with postprostatectomy IMRT versus PBT. Three hundred seven men (IMRT, n = 237; PBT, n = 70) were identified, generating 70 matched pairs.

The study found that although PBT was superior at reducing low-range (volumes receiving 10% to 40% of the dose, respectively) bladder and rectal doses (all P ≤ .01), treatment modality was not associated with differences in clinician-reported acute or late GU/GI toxicities (all P ≥ .05). Five-year grade ≥2 GU toxicity free survival was 61.1% for IMRT and 70.7% for PBT; and 5-year grade ≥3 GU and GI toxicity free survival was >95% for both groups (all P ≥ .05).