Cost-Effectiveness of TME Alone vs. Neoadjuvant Chemoradiotherapy for Stage II and III Rectal Cancer

Abstract

<h3>Purpose/Objective(s)</h3> The role of neoadjuvant chemoradiotherapy in rectal cancer is rapidly evolving. Neoadjuvant chemoradiotherapy (nCRT) reduces the risk of local recurrence in rectal cancer patients, but is associated with increased adverse events, costs, and prolonged treatment time. Pre-operative risk stratification of patients into low- and high-risk categories for local recurrence may identify populations that benefit from nCRT, despite these additional costs. Although total mesorectal excision (TME) alone and nCRT with TME (nCRT/TME) are both in clinical practice, no cost-effectiveness analysis comparing these two treatment approaches in rectal cancer has been published. We sought to determine the cost-effectiveness of primary TME versus nCRT with TME for patients with rectal cancer. <h3>Materials/Methods</h3> We developed a Markov model to simulate the 3-year outcomes of 1 million hypothetical patients as treated on the OCUM trial (NCT 325649) with histologically confirmed invasive carcinoma of the rectum (cT2 to cT4, mC0) with distal tumor margin less than 16 cm from the anal verge undergoing either primary TME or nCRT followed by TME. To calculate the incremental cost-effectiveness ratios, we used utilities and probabilities from the literature and costs from Medicare fee schedules and the Healthcare Bluebook. We discounted utilities and costs at 3% annually. Willingness to pay (WTP) was defined at ICER of $100 000 or less per quality-adjusted life-year (QALY). 1-way sensitivity analyses were performed varying selective model inputs to account for uncertainty. Probabilistic sensitivity analysis (PSA) was conducted. <h3>Results</h3> TME was the dominant strategy compared with nCRT and TME (incremental cost-effectiveness ratio, -$158,201.86/QALY). TME and nCRT/TME were associated with costs of $32,518 and $70,583 and QALYs of 1.91 and 1.67, respectively. TME remained the dominant strategy across all 1-way sensitivity analyses in cost, utility states, and probabilities with the exception of the utilities of the health states post-TME and post-nCRT/TME. When the utility of TME treatment fell below 0.4, nCRT/TME became the dominant strategy. Conversely, when the utility of nCRT/TME treatment rose above 0.69 (.1 above the baseline TME utility), nCRT/TME became the dominant strategy. PSA with 1,000,000 samples revealed TME was the cost-effective strategy in 67.4% of trials. <h3>Conclusion</h3> In patients with rectal cancer, TME was the cost-effective strategy compared with nCRT/TME. TME remained the cost-effective strategy across a range of tested variations in cost, probabilities, and utilities but was sensitive to the utility of TME and nCRT/TME. The results of this study contribute to the growing body of literature decreasing usage of nCRT/TME for patients with rectal cancer, particularly if they have low risk of local recurrence.