A prospective double-blind clinical study: Effect of probiotics and thalidomide on radiation enteritis in patients with pelvic cancer undergoing concurrent chemoradiotherapy.

Abstract

e23013 Background: Radiation induced diarrhea (RID) is one of the commonest and most distressing side effects during and after radiotherapy predominantly in patients whose irradiation region is pelvis. Thalidomide reduces severity as well as the frequency indicated in RID but mechanism of action is not elucidated. Probiotics are beneficial microorganisms that may regulate flora of intestines to increase immunity and have a protective effect on RID. This pilot study was designed to ascertain effects of thalidomide and probiotics on RID in patients being subjected to pelvic irradiation. Methods: A double-blind, single-center, randomized pilot study was conducted. Patients were classified into two groups as thalidomide plus probiotics (Lactobacillus rhamnosus + Probio-M9, ) group (TP group) or plus placebo group (P group).Incidence of grade 3/4 diarrhea, was a primary endpoint of the study. Other secondary endpoints analyzed were rates and severity of diarrhea, antibiotics use, body weight, albumin, and lymphocyte changes. 31 patients undergoing pelvic radiotherapy with or without concurrent chemotherapy were randomly selected from government tertiary general hospital. Results: The incidence of grade 3/4 diarrhea was 9.5% (95% CI: 0 to 24.5%) in TP, which was significantly different from historical data of 30% to 60%. The incidence of grade 3/4 diarrhea in group P was 19.8% (95% CI: 0~41.3%). The frequency and severity of diarrhea in group TP were little less than in group P. There is no significant difference between them. Basically, the time for antibiotic use in groups P and TP was the same, with a slightly longer time from first antibiotic exposure in group TP as compared to group P. The moment of first antibiotics have been prescribed in our study patients, this was better than that of a clinical routine treatment experience and other research data according to the literature. The changes in body weight, albumin level, and lymphocyte at different stages before and after radiotherapy in group TP were not statistically significant, and the level of body weight and albumin in group P was slightly reduced compared with before radiotherapy but increased compared with group TP after radiotherapy. Furthermore, there were no severe adverse effects regarding thalidomide as well as probiotics reported among patients who participated in this study. Conclusions: The combined treatment with thalidomide and probiotics is beneficial to ameliorate RID in patients receiving pelvic radiotherapy, yet this study can't represent whole conclusion due to small size of patients. We will also need larger, multicenter double-blind placebo-controlled trials to confirm exact efficacy and safety of this combined treatment. Clinical trial information: NCT05059613 .