Cost-Utility Analysis of Multigene Assays to Guide Treatment Decisions for Node-Negative Early Breast Cancer

Clinicopathologic and patient factors, such as tumor grade, size, age, and menopausal status, provide limited prognostic and predictive information in hormone receptor positive (HR +), human epidermal growth receptor 2 negative (HER2-), node-negative early-stage breast cancer, leading to potential over- or under-treatment. Multigene expression profile tests used in clinical practice in the USA, including the 21-gene assay, 70-gene assay, 12-gene assay, and 50-gene assay, offer prognostic information beyond traditional clinicopathologic features to improve treatment decisions. This study aimed to estimate the cost-effectiveness of these four multigene assays compared with clinicopathologic risk assessment alone. A decision tree categorized hypothetical patients with HR + /HER2- early-stage invasive breast cancer according to clinical and genomic risk, and integrated clinical expert insights for chemotherapy allocation with literature inputs. A Markov model simulated lifetime costs and outcomes of chemotherapy decisions over a patient's lifetime. The probability of distant breast cancer recurrence was derived from TAILORx (21-gene assay), MINDACT (70-gene assay), and TransATAC (12-gene assay, 50-gene assay) studies. Costs were calculated from a US societal perspective in 2021 US dollars, considering healthcare costs, lost productivity, and patient out-of-pocket expenses. The 21-gene assay and 50-gene assay were less costly ( -$12,189 and -$2410, respectively) and more effective [0.23 and 0.07 quality-adjusted life years (QALYs), respectively] compared with clinicopathologic risk alone. Similarly, the 70-gene assay and 12-gene assay are also cost-effective alternatives [incremental cost-effectiveness ratio (ICER): 27,760 and 7942, respectively]. All four multigene assays were cost-effective from a societal perspective, offering low net lifetime costs or savings with improved outcomes compared with clinicopathologic risk assessment alone. These assays can help refine treatment decisions by providing prognostic risk estimates. In the case of the 21-gene assay, it can also predict chemotherapy benefit leading to the highest lifetime cost savings and greatest QALY gain.