Abstract CT039: Primary analysis of the EORTC 10041/BIG 3-04 MINDACT study: a prospective, randomized study evaluating the clinical utility of the 70-gene signature (MammaPrint …

Background: The MINDACT TRIAL investigated the clinical utility of the 70-gene profile (MammaPrint®), when confronted to the standard clinical pathological (CP) criteria, for the selection of patients unlikely to benefit from adjuvant chemotherapy (CT).Methods: From 2007 to 2011, 11288 patients were screened in 112 centers from 9 countries, of whom 6693 were enrolled. Enrolled patients had undergone successful determination of their genomic risk G (with MammaPrint®) and clinical risk C (modified version Adjuvant! Online). Patients were evaluated as “low clinical risk”, if their 10-year disease specific survival (without CT or endocrine therapy (ET), as estimated by Adjuvant! Online, was greater than 88% for ER-positive patients, and greater than 92% for ER-negative patients. Patients characterized in both assessments as “low- risk” were spared CT while for those “high- risk”, CT was advised. Those with …