Modern pelvic chemoradiotherapy techniques continue to cause bile acid malabsorption

Introduction During treatment with pelvic radiotherapy 80% of patients will develop diarrhoea. Patients with worse acute toxicity are at risk of developing more severe late bowel effects. It has previously been found that 44–57% of patients develop bile acid malabsorption (BAM) during pelvic radiotherapy. In the context of newer radiotherapy techniques, when there should be less small bowel exposure, we aimed to determine whether BAM remains a significant problem in this cohort of patients. Method This study was part of a trial evaluating the role of a gastrointestinal intervention for patients with cervical and bladder cancer receiving chemoradiotherapy. When patients developed lower gastrointestinal symptoms a SeHCAT scan was performed to detect BAM. Demographic and treatment data was recorded in the trial documentation. Results Twenty patients underwent a SeHCAT scan. Ten patients had cervical cancer and 10 had bladder cancer, of which 9 were male. All patients received 20 fractions of radiotherapy over 4 weeks. See table for full demographics. SeHCAT was completed a median 25 days following the start of radiotherapy (28 days for cervix group, 24 days for bladder group). Overall the prevalence of BAM was 65% (13/20). SeHCAT was positive in 90% of the cervix group and 40% of the bladder group. Of the 13 patients who had BAM the prevalence of mild (7-day retention 10–15%), moderate (7-day retention 5–10%) and severe BAM (7-day retention