The impact of 21-Gene Recurrence Score test and classic clinical-pathologic factors in guiding adjuvant therapy for HER-2 negative, ER-positive, early-stage breast cancer.

Both adjuvant hormonal therapy (HT) and chemotherapy (CT) improve survival for women with early-stage breast cancer (ESBC) though recurrence risk reduction is small, and most patients do won’t not benefit from CT it.

The 21-gene Oncotype DX Breast Recurrence Score® test (Oncotype DX, Genomic Health, Inc, Redwood City, CA) has been shown to predict responsiveness to adjuvant CT.2

Recently published prospective studies demonstrated that patients with low Recurrence Score can safely forego adjuvant CT3 leading to Oncotype DX’s inclusion in multiple guidelines to aide treatment decisions. Whether physicians use these tests to influence decision-making is unclear. We examined whether Oncotype DX impacts adjuvant therapeutic decisions for HER-2-negative ESBC patients in Uruguay and whether Recurrence Score is associated with clinicopathological variables.