Structured exercise program following adjuvant chemotherapy for colon cancer: A cost-utility analysis of the CHALLENGE trial.

Abstract

The phase III CHALLENGE trial (CCTG CO.21) demonstrated that a 3-year structured exercise program (SEP) improved disease-free and overall survival versus health education materials (HEM) in patients with stage III or high-risk stage II colon cancer after surgery and adjuvant chemotherapy. We assessed the cost-effectiveness of the SEP versus HEM. This pre-specified economic evaluation used prospectively collected data from all trial participants (n = 889). The base case adopted the Canadian public payer perspective and included direct healthcare costs over a 5-year time horizon with a 1.5% discount rate. 36-Item Short Form (SF-36) outcomes were mapped to Short-Form 6-Dimension (SF-6D) utilities using a validated algorithm. Mean costs (2024 CAD) and effects (life-years (LYs) and quality-adjusted life-years (QALYs)) per participant in each intervention group were used to estimate the incremental costs, incremental LYs/QALYs, incremental cost-effectiveness ratio (ICER, $/life-year gain (LYG)), and incremental cost-utility ratio (ICUR, $/QALY) when applicable. Uncertainty was assessed via bootstrapping (1,000 samples). Notable scenario analyses included a 10-year time horizon and a societal perspective incorporating lost wages due to missed work, measured through the Work Productivity and Activity Impairment questionnaire. In the base case, despite an up-front cost of $2,917 to provide the exercise sessions, the SEP ($31,957) was dominant over HEM ($33,546), being less costly (-$1,589) and more effective (+0.05 LYs; +0.10 QALYs). The SEP was dominant in 53% of bootstrap samples, and 80% fell below a $50,000 per QALY willingness-to-pay threshold. Major cost drivers were cancer recurrence or new malignancy and anticancer therapy. Scenario analyses were consistent with the base case. The SEP was less costly and more effective than HEM. This study can inform payers and health-systems with implementation of SEPs in routine care.