Cost-effectiveness analysis of mammography and clinical breast examination strategies: a comparison with current guidelines

Abstract

Purpose: Breast cancer screening by mammography and clinical breast exam are commonly used for early tumor detection. Previous cost-effectiveness studies considered mammography alone or did not account for all relevant costs. In this study, we assessed the cost-effectiveness of screening schedules recommended by three major cancer organizations and compared them with alternative strategies. We considered costs of screening examinations, subsequent work-up, biopsy, and treatment interventions after diagnosis.

Methods: We used a microsimulation model to generate women's life histories, and assessed screening and treatment effects on survival. Using statistical models, we accounted for age-specific incidence, preclinical disease duration, and age-specific sensitivity and specificity for each screening modality. The outcomes of interest were quality-adjusted life years (QALY) saved and total costs with a 3% annual discount rate. Incremental cost-effectiveness ratios were used to compare strategies. Sensitivity analyses were done by varying some of the assumptions.

Results: Compared with guidelines from the National Cancer Institute and the U.S. Preventive Services Task Force, alternative strategies were more efficient. Mammography and clinical breast exam in alternating years from ages 40 to 79 years was a cost-effective alternative compared with the guidelines, costing $35,500 per QALY saved compared with no screening. The American Cancer Society guideline was the most effective and the most expensive, costing over $680,000 for an added QALY compared with the above alternative.

Conclusion: Screening strategies with lower costs and benefits comparable with those currently recommended should be considered for implementation in practice and for future guidelines.

Figure 1

Model structure for evaluating costs of screening, work-up, biopsy, and treatment for breast cancer. “$” represents accrual of costs, and “+” or “-” represents a positive or negative test result.

Figure 2

Tradeoff plot for strategies A-J (left) and excluding strategy J (right). X-axis is mean total cost in U.S. dollars. Y-axis is mean quality-adjusted life-years. Dominated strategies (B,C,E,G,H) fall below the line of efficiency connecting the non-dominated alternatives (A,D,F,I,J). The plot on the right allows better visualization of strategies A-I.