Cost effectiveness of adjuvant chemotherapy with cyclophosphamide plus methotrexate plus fluorouracil in patients with node positive breast cancer

Background: The analysis of published survival curves can be used as the basis for incremental cost-effectiveness analyses in which two treatments are compared with each other in terms of cost per life year saved. In patients with node-positive breast cancer adjuvant chemotherapy with cyclophosphamide + methotrexate + fluorouracil has been reported to improve survival in comparison with patients who are not given this treatment. Methods: To assess the pharmacoeconomic profile of this adjuvant chemotherapeutic regimen in terms of cost per life-year gained, we conducted an incremental cost-effectiveness analysis in which the Gompertz model was used to calculate the lifetime estimate of the patient-years gained by treated subjects compared to controls. Results: Using data from a published, controlled long-term trial involving 207 patients treated with cyclophosphamide + methotrexate + fluorouracil and 179 controls, we estimated that this adjuvant chemotherapy improved life expectancy by 357 patient-years per 100 subjects. Direct costs, which were almost exclusively related to the administration of chemotherapy, were estimated to be US $159,516 per 100 patients. On the basis of these data, adjuvant chemotherapy was found to imply an incremental cost of US $447 per life-year saved. Conclusions: The cost-effectiveness ratio of adjuvant chemotherapy with cyclophosphamide + methotrexate + fluorouracil in patients with node-positive breast cancer seems to be particularly favourable in comparison with estimates of cost per life-year saved previously calculated for other types of pharmacological intervention.