Cost-effectiveness analysis of Mammostrat® compared with Oncotype DX® to inform the treatment of breast cancer

PURPOSE: To compare the cost-effectiveness of the tumor subtyping assays Mammostrat® and Oncotype DX® for assessing risk of recurrence in early-stage breast cancer and the potential benefit of adjuvant chemotherapy. METHODS: Cost-effectiveness analysis from a US third-party payer perspective. A 10 year Markov model was developed to estimate costs and effects of using each method of risk assessment. The percentages of patients assessed as high, moderate, or low risk were obtained from multicenter, prospective, randomized controlled trials. The analysis simulated the experience of women progressing through various model states representing clinical treatments and subsequent disease. Published recurrence data for Mammostrat® were adjusted appropriately to account for differences between definitions and samples of Oncotype DX® and Mammostrat® in the original clinical trials. Cost and utility data were obtained from previously published studies. Sensitivity analyses examined how base-case results might differ when input values and assumptions varied. RESULTS: Base-case costs for women assessed using Mammostrat® were $15,782, compared with $18,051 for women assessed with Oncotype DX®. Thus, cost savings of $2,268 resulted from using Mammostrat®. Both Mammostrat® and Oncotype DX® resulted in similar life years (9.880 and 9.882) and quality-adjusted life years (7.935 and 7.940), respectively. Sensitivity analyses demonstrated that the assumptions made about recurrence are the key drivers of model results. DISCUSSION: Cost savings associated with the use of Mammostrat® instead of Oncotype DX® are largely due to the difference in cost between the two tests. Since survival and quality-adjusted life years were similar using either assay, Mammostrat® has economic advantages for women with early-stage breast cancer.