Abstract Introduction: The Oncotype DX was associated to 14% of adjuvant chemotherapy administration to Hormonal Receptor positive (HR+) and HER2 negative, T1N0 or T2N0 breast cancer patients at Tailor X trial recently published (RS>25) Objective: To describe the adjuvant chemotherapy administration to a Brazilian public hospital for HR+ HER2 negative, T1N0 or T2N0 breast cancer patients. And the estimate the cost effectivity of Oncotype DX in our low income scenary. Materials and Methods:This retrospective cross-sectional study was conducted at the Oncology Division of the Women's Hospital - CAISM of the State University of Campinas (UNICAMP), Brazil. All patient data were found from the hospital records from 2007 to 2009. It was included T1N0 and T2N0 HR+/HER2 negative breast cancer patients. Patients submitted to neoadjuvant treatment were excluded. We calculate the final cost of different types of chemotherapy used and the potential impact to oncotype DX introduction in this scenary. Results: It was found 109 patients records. 66% (72/109) had received adjuvant chemotherapy. 35% (38/109) had AC (X6), 29% (32/109) had CMF (X6) and 2% (2/109) had AC-T (X4). The total cost for chemotherapy scheme were; AC (X6) US$ 346,9; CMF (X6), US$300,6; ACT (X4), US$395,9. The total cost of chemotherapy was US$ 23.596,83 to 72 patients. If we consider 14% (15/109) of adjuvant chemotherapy associate to a Oncotype DX use (Tailor X RS>25), It would reduce adjuvant chemotherapy administration to 15 patients. The chemotherapy cost would be US$ 4588,27. In our scenary, It could save US$ 19.008,56. Nevertheless, the Oncotype Dx cost to Brasil is US$ 3.200,00 for each test. To 109 patients the total cost would be (109 X US$ 3.200,00) US$ 348.800,00. Therefore, the total cost for Oncotype DX program plus adjuvant chemotherapy for our patients would be US$ 348.800,00 + US$ 4.588,27= US$ 353.388,27. While in the real situation we had spent US$ 23.596,83. The total estimate cost would be 15 times more. Conclusion: At the moment, because of the assay high cost and the low cost of the adjuvant chemotherapy to HR+, HER2 negative T1N0 and T2N0, It would be difficult to consider Oncotype DX cost-effective to Brazilian public heath system. Even considering many advantages to spare chemotherapy to this population. Citation Format: Cabello C, de Andrade RN, Cabello TF, Teixeira S, da Costa LS, Ramalho S. Oncotype DX cost effectivity to a Brazilian public hospital [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-15-04.