Assessment of acute bowel function after radiotherapy for prostate cancer: Is it accurate enough?

Pelvic radiotherapy for prostate cancer can be associated with bowel toxicity, which may have a significant impact on quality of life. Our aim was to assess the adequacy of the tools currently used to assess bowel symptoms after radiotherapy, including physician and patient reported outcomes. This sub-study on acute toxicity was part of a prospective trial assessing long-term bowel dysfunction.

Between February 2013 and July 2015, 75 patients with prostate cancer who received radiotherapy completed the LENT/SOMA and the EPIC questionnaires baseline and 2 weeks after the treatment. The Bristol stool scale and two additional questions on faecal urgency were added. Physicians assessed toxicity using Common Terminology Criteria for Adverse Events v.4.0. Agreement between patients and clinicians was assessed using the Cohen's κ coefficient.

Acute toxicity during radiotherapy was very low. The pattern of overall bowel bother was similar before and after treatment. Faecal urgency significantly increased after radiotherapy compared to baseline but was only detected by the additional questions and not by the physicians or the patient-reported outcomes (PRO) questionnaires. Correlation between physician and PRO was poor for most symptoms.

Bowel symptoms such as urgency may remain undetected by usual tools to assess toxicity after radiotherapy. Assessment of bowel toxicity should be reappraised in order to identify those patients who may have symptoms with an impact on their quality of life.