The most frequent early gastrointestinal (GI) toxicity symptoms are nausea (58%), diarrhea (46.7%), and vomiting (45.5%) in patients with cervical cancer (CC). Approximately 90% of patients undergoing abdominopelvic radiotherapy present with changes in the GI tract, such as degenerative alterations in mucosal epithelial cells and nutrient malabsorption.

To evaluate the effect of a diet modified in fiber, lactose, and fat on the prevention of chemoradiotherapy (QTRT)-induced GI toxicity compared to the usual prescription in women with locally advanced CC.

A total of 134 women with a confirmed diagnosis of CC in locally advanced stages (IB2-IVA) were included in a randomized clinical trial conducted between February 2017 and March 2020. The intervention group (IG) received a modified diet of fiber, lactose, and fat, while the usual prescription group (UP) followed habitual nutritional recommendations. Toxicity was measured using the Common Terminology Criteria for Adverse Events (CTCAE) v4.

A total of 134 women were included in the IG (65) and UP (69) groups. The mean age in the IG and UP groups were 47.2±13.4 and 49.7±14.2 years, respectively. Radiotherapy doses received by the IG and UP groups were 50.1±6.7 and 49.9±4.6 Gy, respectively. IG had a lower risk of presenting with mild constipation compared to the UP (hazard ratio: 0.46, 95% confidence interval: 0.28-0.76, P<0.01).

Patients with locally advanced stages of CC undergoing QTRT who received fiber, lactose, and fat-modified diet may have a lower risk of mild constipation during abdominal radiotherapy.