Diarrhoea in irradiated patients: a prospective multicentre observational study.

AIMS: To determine the incidence of cancer treatment-induced diarrhoea in patients submitted to irradiation. METHODS: Forty-five Italian radiation oncology departments took part in this prospective observational study and a total of 1020 patients were enrolled. The accrual lasted three consecutive weeks; evaluation was based on diary cards filled in daily by patients during radiotherapy and one week after cessation. Diary cards recorded both the onset and intensity of diarrhoea. RESULTS: A total of 1004 patients were eligible for this analysis. 147/1004 (14.6%) patients had diarrhoea. The median minimum number of daily events was 1 (range 1-7) with a median maximum events of 3 (range 1-23). 82/147 patients (56.2%) had a drug prescription for diarrhoea. In the evaluation of the onset of diarrhoea, in multivariate analysis, we found the following factors to be statistically significant predictors of an increased likelihood of diarrhoea: primitive tumour site, therapeutic purpose and field size. CONCLUSIONS: Patients with abdominal-pelvic cancer, treated with curative purpose and using large field sizes are at high risk of cancer treatment-induced diarrhoea. Diarrhoea was also observed in patients treated at other sites. In this population group there is the need for more stringent monitoring during the delivery of radiation therapy.