Effect of inulin and fructo-oligosaccharide on the prevention of acute radiation enteritis in patients with gynecological cancer and impact on quality-of-life: a randomized, double-blind, placebo-controlled trial.

Background/objectives: The pathogenesis of enteritis after abdominal radiotherapy (RT) is unknown, although changes in fecal microbiota may be involved. Prebiotics stimulate the proliferation of Lactobacillus spp and Bifidobacterium spp, and this may have positive effects on the intestinal mucosa during abdominal RT.

Subjects/methods: We performed a randomized, double-blind, placebo-controlled trial involving patients with gynecological cancer who received abdominal RT after surgery. Patients were randomized to receive prebiotics or placebo. The prebiotic group received a mixture of fiber (50 inulin and 50% fructo-oligosaccharide), and the placebo group received 6 g of maltodextrin twice daily from 1 week before to 3 weeks after RT. The number of bowel movements and stool consistency was recorded daily. Diarrhea was evaluated according to the Common Toxicity Criteria of the National Cancer Institute. Stool consistency was assessed using the 7-point Bristol scale. Patients' quality-of-life was evaluated at baseline and at completion of RT using the EORTC-QLQ-C30 (European Organization for Research and Treatment of Cancer quality-of-life Questionnaire C30) test.

Results: Thirty-eight women with a mean age of 60.3±11.8 years participated in the study. Both groups (prebiotic (n=20) and placebo (n=18)) were comparable in their baseline characteristics. The number of bowel movements per month increased in both groups during RT. The number of bowel movements per day increased in both groups. The number of days with watery stool (Bristol score 7) was lower in the prebiotic group (3.3±4.4 to 2.2±1.6) than in the placebo group (P=0.08). With respect to quality-of-life, the symptoms with the highest score in the placebo group were insomnia at baseline and diarrhea toward the end of the treatment. In the prebiotic group, insomnia was the symptom with the highest score at both assessments, although the differences were not statistically significant.

Conclusions: Prebiotics can improve the consistency of stools in gynecologic cancer patients on RT. This finding could have important implications in the quality-of-life of these patients during treatment.