Impact of the Intermediate Oncotype DX Recurrence Score results on adjuvant treatment recommendations in hormone receptor-positive early breast cancer in a single center.

e11560 Background: The Oncotype DX (ODX) Breast Cancer assay (Genomic Health NC., Redwood City, CA) has been validated as a predictor of the likelihood of chemotherapy benefit in hormone receptor positive (HR+) early stage breast cancer (ESBC). It classifies patients (pts) into 3 risk recurrence categories: low ( 30). For pts with high recurrence score (RS), the benefit from adjuvant chemotherapy is significant, while is minimal for pts with low RS. In the intermediate recurrence score (IRS) category, adjuvant chemotherapy is controversial. We evaluated the impact of IRS on our adjuvant treatment decisions pre and post-testing. Methods: We retrospectively analyzed a cohort of 37 pts with IRS by Oncotype DX assay at the Basurto University Hospital from September 2012 to December 2014. They were breast tumor surgical specimens, HR+, Her 2 negative, tumor size T1b (if at least two histological unfavorable characteristic: high histological grade, lymphatic invasion an...