Chronic pain after colorectal cancer treatment: A population-based cross-sectional study.

Aims: With the recently validated tool for estimating chronic pain after colorectal cancer surgery, the aims of this study were to calculate the prevalence and to identify predictive risk factors for chronic pain after colorectal cancer treatment.

Method: Clinical data from colorectal cancer patients treated between 2001 and 2014 were obtained from the Danish Colorectal Cancer Group database. In 2016, all survivors were invited to participate in a national cross-sectional questionnaire study on long-term functional outcomes, including the chronic pain questionnaire. The prevalence of chronic pain was analysed in groups based on demographic data and treatment-related factors. Multivariate logistic regression analysis was performed to determine significant predictors of chronic pain, displayed as odds ratios (OR) and 95% confidence intervals.

Results: The response rate was 63.8%, representing 11 600 patients (7127 colon and 4473 rectal cancer patients). The overall prevalence of pain was 41.5%, with 15.4% having major pain. Major pain was more prevalent in rectal cancer patients than colon cancer patients (16.7% vs. 14.5%, p < 0.001). Predictors for major pain were: young age <60 years [OR 1.7 (95% CI 1.51-1.91)]; female sex [OR 1.63 (95% CI 1.46-1.82)]; an open surgical approach [OR 1.18 (95% CI 1.05-1.33)]; chemotherapy [OR 1.32 (95% CI 1.18-1.49)]; radiotherapy [OR 1.39 (95% CI 1.17-1.65)]; permanent stoma [1.56 (95% CI 1.31-1.86)]; comorbidity [OR 1.69 (95% CI 1.5-1.9)]; anastomotic leakage [OR 1.31 (95% CI 1.05-1.64)].

Conclusion: Chronic pain is prevalent after colorectal cancer surgery. All patients should be informed about the risks before cancer treatment, particularly those who are at an increased risk of developing major pain.