Cost-Effectiveness Analysis of Total Neoadjuvant Therapy Followed by Radical Resection Versus Conventional Therapy for Locally Advanced Rectal Cancer.

Background: Definitive surgery with total mesorectal excision is the mainstay of treatment for locally advanced rectal cancer. Multimodality therapy improves long-term survival. Current standards advise neoadjuvant chemoradiation followed by radical surgery and adjuvant chemotherapy. Nationally, compliance with adjuvant chemotherapy is only 32%. New research evaluates the effectiveness of total neoadjuvant therapy: complete chemotherapy and chemoradiation before surgery.

Objective: The aim of this study is to determine the favored treatment for locally advanced rectal cancer by comparing the cost-effectiveness of total neoadjuvant therapy and the current standard of care.

Design: Decision analytical modeling using long-term costs and 5-year disease-free survival was performed to determine the cost-effectiveness after total neoadjuvant therapy and the current standard of care. Sensitivity analysis was used to investigate the effect of uncertainty in model parameters.

Settings: Centers for Medicare & Medicaid Services billing data perspective was adopted and outcomes modeled according to local and national databases and literature consensus.

Patients: Adult patients with stage II or III rectal cancer were selected.

Main Outcome Measures: Cost-effectiveness in disease-free life-years, incremental cost-effectiveness ratio, and net monetary benefit were determined over a 5-year posttreatment period. The favored strategy was determined based on cost-effectiveness and sensitivity analyses.

Results: Cost-effectiveness for total neoadjuvant therapy was 40,708 $/life-year, and, for conventional therapy, cost-effectiveness was 44,248 $/life-year. Sensitivity analysis showed that, for an estimated total neoadjuvant therapy completion rate of 90%, total neoadjuvant therapy would remain the dominant strategy for any adjuvant chemotherapy completion rate of less than 93%.

Limitations: The samples used to calculate completion rates are small, and survival probabilities are based on existing literature, local database values, and consensus estimates. The model encompasses a 5-year time period from diagnosis.

Conclusions: Cost-effectiveness analysis shows that a strategy of total neoadjuvant therapy followed by radical surgery is favored over the current standard of care for locally advanced rectal cancer. Sensitivity analysis shows that a low rate of adjuvant chemotherapy administration plays a key role in decreasing the cost-effectiveness of the current standard of care. See Video Abstract at http://links.lww.com/DCR/A942.