Background: Acute gastrointestinal symptoms affect 90% of patients during pelvic radiotherapy. Elemental diet is protective in animal models. A nonrandomized study suggested benefit from a partial elemental diet. A pilot study suggested that radiotherapy patients only tolerate oral elemental diet comprising one-third of total calories for 3 weeks.
Aim: To assess the feasibility and efficacy of replacing one-third of normal diet with elemental diet during the first 3 weeks of pelvic radiotherapy in reducing acute gastrointestinal toxicity.
Methods: Patients were randomized to elemental diet or no intervention. Toxicity was assessed using the Inflammatory Bowel Disease Questionnaire, Vaizey Incontinence scale and Radiation Therapy Oncology Group tool. Faecal calprotectin measured intestinal mucosal inflammation.
Results: Twenty-nine women and 21 men, median age 61.5 years were randomized. Patients taking elemental diet did not have lower gastrointestinal toxicity ratings or inflammatory markers (P > 0.2). The mean dose taken was 21% (2-36%) of total caloric requirements.
Conclusions: Patients cannot tolerate large volumes of oral elemental diet. The quantities consumed in this study produced no therapeutic benefit. Future studies should aim to replace a higher proportion of nutritional intake for a longer duration of radiotherapy treatment.