Cost consequence model of the MammaPrint (70-gene signature) and 21-gene signature in patients with primary HR+HER2-, N1 early-stage breast cancer in Germany.

534 Background: The MammaPrint 70-gene and Oncotype DX 21-gene signatures serve to stratify breast cancer tumors, distinguishing between those with low or high risk of distant metastasis. Patients with a low genomic risk tumor have the option to avoid overtreatment by omitting chemotherapy and minimize associated toxicities. This analysis evaluates the economic impact of implementing MammaPrint, Oncotype DX (ODx), or no gene signature testing for patients with HR+ HER2- early breast cancer with 1 to 3 positive lymph nodes (N1) in Germany. Methods: We constructed a cost-consequence model to assess the budget implications of MammaPrint, ODx, and not employing a gene signature, considering both the healthcare payers and societal perspective. The model focuses on patients with HR+/HER2-/N1 breast tumors who, in the absence of a gene expression analysis, would receive chemotherapy in 63% of cases according to the data of the certified breast cancers in Germany. Input data were sourced from MINDACT, RxPONDER, literature, the EBM, the DRG system. The healthcare payer perspective covers testing, direct/indirect costs of chemotherapy, and disease recurrence costs. The societal perspective adds transport costs and productivity losses to these. Results: A projected 9,207 HR+/HER2-/N1 breast cancer patients were candidates for genomic testing. In MINDACT, patients were classified as MammaPrint Low Risk in 73% of cases, and in RxPONDER 83% of patients were categorized as ODx Low Risk (RS 0-25). The model demonstrated per patient savings from a healthcare payer perspective of €3.766 for MammaPrint and €900 for ODx compared to not using any gene signature for N1 breast cancer patients in Germany. Importantly, the savings are even more substantial from a societal perspective, reaching €11.815 for MammaPrint and €11.243 for ODx. When limiting the population to women >50 years, similar results were observed with per patient savings from a payer perspective of €3.766 and €1.549, and from a societal perspective of €9.826 and €9.349, for MammaPrint and ODx, respectively. Conclusions: These data demonstrate that personalized treatment planning with genomic testing for breast cancer with HR+/HER2-/LN1 breast cancer, leads to a reduction in chemotherapy use and associated costs in Germany. Although MammaPrint designates a smaller proportion of genomically high risk patients compared to ODx, MammaPrint Low Risk patients without chemotherapy demonstrate higher survival outcomes. Consequently, any increased chemotherapy costs are offset by lower testing and distant recurrence expenses, making MammaPrint a cost-conscious option.