[Cost-effectiveness analysis of adjuvant anastrozol in post-menopausal women with breast cancer].

OBJECTIVES

Carry out an economic analysis of the incorporation of anastrozole as adjuvant hormone therapy in postmenopausal women with breast cancer in a Brazilian setting.

METHODS

The cost-effectiveness estimate comparing anastrozole to tamoxifen was made from the perspectives of the patient, private health insurance, and government. A Markov model was designed based on data from ATAC trial after 100 months follow-up in a hypothetical cohort of 1000 postmenopausal women in Brazil, using outcomes projections for a 25-year period. Resource utilization and associated costs were obtained from preselected sources and specialists' opinions. Treatment costs varied according to the perspective used. The incremental benefit was inserted in the model to obtain the cost of quality-adjusted life-year gained (QALY).

RESULTS

Benefit extrapolations for a 25-year time line showed an estimate of 0.29 QALY gained with anastrozole compared to tamoxifen. The cost-effectiveness ratio per QALY gained depended on which perspective was used. There was an increment of R$ 32.403,00/QALY in the public health system/government, R$ 32.230,00/QALY for private health system, and R$ 55.270,00/QALY for patients.

CONCLUSION

The benefit from adjuvant anastrozole in postmenopausal patients with breast cancer is associated to major differences in cost-effectiveness ratio and varies with the different perspectives. According to current WHO parameters, the increment is considered acceptable under public and private health system perspectives, but not from that of the patient.