Topical butyrate for acute radiation proctitis: randomised, crossover trial

Background No available therapy has, as yet, proven effective to treat acut e radiation proctitis (ARP) following radiation therapy for malignant pelvi c 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 G y external-beam radiation therapy for pelvic malignant disease, were treate d for 3 weeks with topical sodium butyrate and saline enemas according to a randomised, double-blind, crossover protocol. Clinical, endoscopic, and hi stological 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 multipl e response for ordered categorical data. Findings Topical butyrate, but not saline, led to remission of symptoms (cl inical score from 8.2 [SE 1.6] to 1.5 [0.7] vs 7.9 [1.8] to 8.1 [3.4]). Whe n the treatment regimen was switched, eight out of nine of the previously p lacebo-treated patients went into remission, whereas three patients relapse d when switched to saline. The advantage of butyrate over placebo, expresse d as CI, odds ratio, and p value was significant for almost all the clinica l, endoscopic and histological factors taken into consideration. Interpretation Topical sodium butyrate, unlike other therapeutic regimens u sed so far, proved effective in the treatment of ARP.