Effects of Probiotic Lactobacillus Casei DN-114 001 in Prevention of Radiation-Induced Diarrhea: Results From Multicenter, Randomized, Placebo-Controlled Nutritional Trial

Purpose To determine whether a probiotic drink containing Lactobacillus casei DN-114 001 reduces the incidence of radiation-induced diarrhea in patients with gynecologic cancer. Methods and Materials Patients who were undergoing pelvic radiotherapy (45–50 Gy, conventional fractionation) for either cervical carcinoma (radiotherapy and weekly cisplatin) or endometrial adenocarcinoma (postoperative radiotherapy) were randomly assigned to a probiotic drink or placebo, in a double-blind fashion. The probiotic drink consisted of liquid yogurt containing L. casei DN-114 001 at 108 CFU/g. The patients recorded the daily the number of bowel movements and scored the stool consistency using the Bristol scale. Diarrhea was graded weekly according the Common Toxicity Criteria system. The primary endpoint was to reduce the incidence of diarrhea, defined by a Common Toxicity Criteria Grade of 2 or greater or the need for loperamide. Results A total of 85 patients were enrolled. Grade 2 or greater diarrhea and/or the use of loperamide was observed in 24 of 41 patients in the placebo group and 30 of 44 in the probiotic group ( p = 0.568). No differences were found in the median time to the presentation of the primary endpoint. Probiotic intervention had a significant effect on stool consistency ( p = 0.04). The median time for patients to present with Bristol scale stools of Type 6 or greater was 14 days for patients receiving the probiotic drink vs. 10 days for those receiving placebo. Conclusion Nutritional intervention with the probiotic drink containing L. casei DN-114 001 does not reduce the incidence of radiation-induced diarrhea as defined by a Common Toxicity Criteria Grade 2 or greater. However, it had a significant effect on stool consistency as measured by the Bristol scale.