Is supplementation with elemental diet feasible in patients undergoing pelvic radiotherapy?

Acute gastrointestinal upset occurs in approximately 80% of patients undergoing radiotherapy for pelvic cancers. Underlying changes relate to denudation of the mucosal layer which renders the small intestine vulnerable to additional damage from proteolytic enzymes and bile acids. Severe acute bowel symptoms may predispose to progressive fibrotic and ischaemic changes. Elemental diet given during treatment may reduce acute and chronic bowel symptoms induced by pelvic radiotherapy.

This study aimed to assess compliance with elemental diet during pelvic radiotherapy. Patients with gynaecological, urological or rectal malignancy undergoing radical or adjuvant pelvic radiotherapy were randomised to one of five groups. Each group was assigned a target quantity of three different elemental sip feeds (Group 1, 20%, Group 2, 50%, Group 3, 75% of calorie requirements taken as E028 extra liquid; Group 4, 50% of calorie requirements taken as E028 extra powder; Group 5, 50% of calorie requirements taken as Emsogen powder). Compliance was assessed using a diary card and weekly assessment. Statistical analyses were conducted on an intention to treat basis.

Fifty patients (44 female, six male) mean age 58 yr (95% CI 55-61), were recruited to the study (24 endometrial, 17 cervical, 7 rectal, 1 vulval and 1 bladder carcinoma). Mean weight at baseline was 74.5 kg (95% CI 69-80) and this did not change during treatment. Full compliance was achieved in three patients, all from Group 1. By week 5, only 46% of patients were consuming elemental diet. Post hoc analysis of variance with repeated measures indicated that there were no significant differences in volume of elemental diet consumed between groups (P = 0.937). There was a significant inverse linear relationship between intake of elemental diet and time (P < 0.001).

Different formulations of elemental diet do not influence compliance. Patients are unlikely to be able to consume more than one-third of their calorie requirements in the form of an elemental sip feed. Further investigation is warranted to determine if intervention with this volume of elemental diet is beneficial.