A Markov model assessing the effectiveness and cost-effectiveness of FOLFOX compared with FOLFIRI for the initial treatment of metastatic colorectal cancer

Objective: To analyze the efficacy and cost-effectiveness of FOLFOX compared with FOLFIRI for patients with metastatic colorectal cancer. Method: We developed a Markov decision model using a hypothetical cohort of patients with metastatic colorectal cancer to compare beginning chemotherapy with FOLFOX or FOLFIRI. Probabilities of toxicities, including neutropenia, diarrhea, and neuropathy, were based on published literature for FOLFOX and FOLFIRI. Costs for physician and hospital services unadjusted for geographic location were estimated using Centers for Medicare and Medicaid services reimbursement data. Drug costs were estimated using Medicare B reimbursement and the Federal Supply Schedule. Health outcomes were measured in quality-adjusted life years (QALYs). Univariate and probabilistic sensitivity analyses were performed to address uncertainty in the model parameters. Results: The FOLFOX strategy provided 1.003 QALYs at a cost of $29,865, whereas FOLFIRI provided 0.921 QALYs at a cost of $24,551. The incremental cost-effectiveness ratio for FOLFOX treatment was $65,170/QALY. In 10,000 probabilistic Monte Carlo simulations, FOLFOX was cost-effective in 48.59% of trials using a $50,000/QALY threshold. The most influential variables in univariate sensitivity analysis were the expected years of survival associated with each chemotherapy regimen. Conclusions: FOLFOX and FOLFIRI are similar in terms of costs and benefits. The slight QALY benefits associated with FOLFOX are within the range of $100,000/QALY, an accepted threshold in oncology.