Cost-effectiveness of the Oncotype DX Breast Recurrence Score test in postmenopausal women with node-positive early breast cancer based on the RxPONDER trial.

Abstract

534 Background: The Oncotype DX test is a predictive and prognostic multigene assay used to guide adjuvant chemotherapy in HR+/HER2- early breast cancer. The ability of the Oncotype DX test to predict the benefit of chemotherapy in node-positive early breast cancer was demonstrated in SWOG-8814. This evidence, in combination with findings from a bespoke analysis of the TransATAC study, informed an economic evaluation of the Oncotype DX test by the National Institute for Health and Care Excellence in the UK. This study examined the impact of new evidence from the RxPONDER trial on the cost-effectiveness of the Oncotype DX test in postmenopausal women with node-positive early breast cancer. Methods: The cost-effectiveness of the Oncotype DX test compared to clinical risk tools only in postmenopausal HR+/HER2- early breast cancer was estimated using a model in Microsoft Excel. The pre-RxPONDER analysis using the old cut points (RS 0-17, RS 18-30, RS 31-100) was informed by TransATAC and SWOG-8814. The model was updated with 5-year probability of distant recurrence as first site estimates based on new RS cut points (RS 0-25, RS 26-100) from RxPONDER. The impact on incremental lifetime costs and quality-adjusted life-years (QALYs) gained was examined based on the list price for the Oncotype DX test in the UK. Results: The impact of adding data from RxPONDER into the cost-effectiveness analysis is summarized in the table below. Conclusions: The RxPONDER trial demonstrated that the addition of chemotherapy to endocrine therapy had no benefit for distant recurrence in postmenopausal women with RS 0-25, regardless of clinical features, which suggests that most patients with 1-3 positive nodes can be safely spared adjuvant chemotherapy. In the model this was reflected in reduced cost of chemotherapy and higher QALYs from avoiding short and long-term adverse effects of chemotherapy. Targeted chemotherapy of a minority (17%) of patients with RS 26-100 reduced the cost of distant recurrence and improved survival based on the model results. RxPONDER provides direct evidence to inform the probability of distant recurrence with endocrine and chemo-endocrine therapy, whilst previous models have had to synthesize multiple sources of DRFI and chemotherapy treatment effect. Future studies should examine the impact of the RxPONDER findings on chemotherapy treatment decision-making in routine clinical practice.[Table: see text]