Brasó Maristany, FaraGriguolo, GaiaChic Ruché, NúriaPascual, TomásParé Brunet, LaiaMaues, JuliaGalván, PatriciaDieci, Maria VittoriaMiglietta, FedericaGiarratano, TommasoMartínez Sáez, OlgaMarín Aguilera, MercedesSchettini, FrancescoConte, BenedettaAngelats, LauraVidal Losada, Maria JesúsAdamo, BarbaraMuñoz, MontseSanfeliu, EstherGonzález Farré, BlancaVivancos, AnaVillagrasa, PatriciaParker, Joel S.Perou, Charles M.Conte, PierfrancoPrat Aparicio, AleixGuarneri, Valentina2023-03-012023-12-312022-120027-8874https://hdl.handle.net/2445/194390In advanced HER2-positive (HER2+) breast cancer (BC), the new antibody-drug conjugate trastuzumab deruxtecan (T-DXd) is more effective compared to trastuzumab emtansine (T-DM1). However, T-DXd can have significant toxicities, and the right treatment sequence is unknown. Biomarkers to guide the use of anti-HER2 therapies beyond HER2 status are needed. Here, we evaluated if pre-established levels of ERBB2 mRNA expression according to the HER2DX standardized assay are associated with response and survival following T-DM1. In ERBB2 low, medium, and high groups, the overall response rate was 0%, 29% and 56%, respectively (P<.001). ERBB2 mRNA was significantly associated with better progression-free survival (p = 0.002) and overall survival (OS; P = 0.02). These findings were independent of HER2 IHC levels, hormone receptor, age, brain metastasis and line of therapy. The HER2DX risk-score (P=.04) and the immunoglobulin (IGG) signature (P=.04) were significantly associated with OS since diagnosis. HER2DX provides prognostic and predictive information following T-DM1 in advanced HER2+ BC.14 p.application/pdfeng(c) Brasó Maristany, Fara et al., 2022Tumors cerebralsMetàstasiCàncer de mamaExpressió gènicaCèl·lules TBrain tumorsMetastasisBreast cancerGene expressionT cellsinfo:eu-repo/semantics/article7316922023-03-01info:eu-repo/semantics/openAccess36576009