Patient reported long‐term side effects on bowel function and anal pain in anal cancer survivors – 3‐ and 6‐year results from the Swedish national ANCA study

Abstract

AimThe primary therapeutic option for anal cancer treatment is chemoradiotherapy resulting in 80% survival. The aim of this study was to assess long‐term bowel function impairment and anal pain at 3 and 6 years after anal cancer diagnosis, based on a hypothesis of an increase in impairment over time. A secondary aim was to investigate if chemoradiotherapy increased the risk for bowel impairment, compared to radiotherapy alone.MethodThe ANal CAncer study (ANCA) consists of a national Swedish cohort of patients diagnosed with anal cancer between 2011–2013. Patients within the study were invited to respond to a study‐specific questionnaire at 3‐ and 6‐years after diagnosis. Descriptive analyses for the primary endpoint and ordinal logistic regressions for secondary endpoint were performed.ResultsA total of 388 patients (84%) were included in the study. At 3 years of follow‐up, 264 patients were alive. A total of 195 of these patients (74%) answered a study specific questionnaire, and at 6 years 154 patients (67%). Fifty‐seven percent experienced bowel urgency at both 3 and 6 years. There was an increased risk for repeated bowel movement within 1 h (OR 2.44 [95% CI: 1.08–5.61, p = 0.03]) at 3 years in patients who had been treated by chemoradiation compared to radiotherapy alone.ConclusionsImpairment in bowel function and anal pain after anal cancer treatment should be expected and remains after 6 years. This suggests that long‐term follow‐up may be necessary in some form after customary follow‐up. The addition of chemotherapy increases long‐term side effects of bowel function.