Topical butyrate for acute radiation proctitis: randomised, crossover trial

Background No available therapy has, as yet, proven effective to treat acute radiation proctitis (ARP) following radiation therapy for malignant pelvic disease. We assessed whether sodium butyrate enemas, at a dose of 80 mmol/L (80 mL/24 h), might offer effective treatment for this condition. Methods 20 patients presenting with ARP after completing a cycle of 35-52 Gy external-beam radiation therapy for pelvic malignant disease, were treated for 3 weeks with topical sodium butyrate and saline enemas according to a randomised, double-blind, crossover protocol. Clinical, endoscopic, and histological findings were assessed at enrolment, at week 3, and then at the end of the study. Data were analysed by two-tailed t test for paired data (continuous variables) and a logistic-regression model with variable multiple response for ordered categorical data. Findings Topical butyrate, but not saline, led to remission of symptoms (clinical score from 8.2 [SE 1.6] to 1.5 [0.7] vs 7.9 [1.8] to 8.1 [3.4]). When the treatment regimen was switched, eight out of nine of the previously placebo-treated patients went into remission, whereas three patients relapsed when switched to saline. The advantage of butyrate over placebo, expressed as CI, odds ratio, and p value was significant for almost all the clinical, endoscopic and histological factors taken into consideration. Interpretation Topical sodium butyrate, unlike other therapeutic regimens used so far, proved effective in the treatment of ARP.