Rectal Cancer Pain Score: A prospective cohort validation study across recovery stages

Chronic pain affects approximately 30% of rectal cancer (RC) survivors, significantly impairing their quality of life (QoL). The Rectal Cancer Pain Score (RCPS) was developed to evaluate chronic pain in RC patients. While its psychometric properties have been demonstrated in cross-sectional studies on long-term survivors, validation in a longitudinal cohort is necessary to establish its utility throughout recovery.

Patients undergoing RC surgery at three Danish hospitals were enrolled in a prospective cohort-screening program for late sequelae. Patients completed the RCPS, the EQ-5D-5L questionnaire and a question regarding the impact of pain on QoL (scored from 1, 'Not at all' to 5 'Very much') at 3-, 12-, 24- and 36 months post-surgery. The RCPS's validity was assessed through the predictive ability of requests for pain-related contact, correlations with self-rated pain impact and associations with QoL. Known-groups validity was evaluated by comparing pain impact and pain referrals.

A total of 729 patients (mean age 67 years, 36% female) were included. Higher pain scores at 12 months significantly predicted requests for future contacts regarding pain (p < 0.001), supporting predictive validity. The RCPS demonstrated strong concurrent validity, correlating highly with self-rated pain impact (p < 0.001), and there were significant differences in the request for contact between pain impact groups (p < 0.001), confirming construct and known-group validity.

The RCPS is a valid tool for screening rectal cancer patients prospectively for chronic pain during the follow-up period. Its integration into routine follow-up programs may enable earlier identification and tailored management of chronic pain.