Topical butyrate for acute radiation proctitis: randomised, crossover trial

Abstract

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 enrollment, 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.