HER2DX is a 27-gene assay for early-stage HER2+ breast cancer based on clinical data and the expression of 4 signatures (immune, proliferation, luminal, HER2). Here we evaluated utility in IBC first time. Standardized was centrally baseline pre-treatment tumors from prospective phase II trial (NCT01796197), which patients with were treated neoadjuvant paclitaxel, trastuzumab pertuzumab (THP) x ...