Abdominal and pelvic radiotherapy (RT) reduces the renewal capacity of the epithelium. Rectal biopsies obtained from patients receiving pelvic RT have revealed atrophy of surface epithelium, acute cryptitis, crypt abscesses, crypt distortion and atrophy, and stromal inflammation. Modifications in intestinal microbiota, such as an increase in the number of pathogens, may contribute to intestinal injury. The prebiotic effect of a carbohydrate is assessed by its capacity to stimulate the proliferation of healthy bacteria (Bifidobacterium, Lactobacillus) rather than pathogenic bacteria (Clostridium, E. coli).

The hypothesis of the study is that a mixture of inulin and fructooligosaccharide could modulate Lactobacillus and Bifidobacterium and reduce the intestinal injury in patients affected of gynaecological cancer and treated with abdominal radiotherapy.

Inclusion Criteria:

• female gender, age ≥ 18 years, and a diagnosis of gynaecologic cancer requiring postoperative pelvic RT.

Exclusion Criteria:

• previous RT, previous or adjuvant chemotherapy, other types of pelvic tumours or other gynaecologic malignancies, antibiotic or immunosuppressive treatment one week before inclusion or during treatment, and the presence of acute or chronic gastrointestinal disease contraindicating ingestion of the fibre