Abstract 29P
The development of FGFR inhibitors, Multi-Tyrosine Kinase Inhibitors (MTKI) and specific FGFR1-4 inhibitors (FGFRinh) has been focused in FGFR-amplified (FGFRamp) BC patients (pt). However, previous results suggested that clinical benefit with FGFRinh was limited to tumours with high FGFR copy number alterations (CNA), resulting in high FGFR expression. Here, we aimed to study whether FGFR1-4 mRNAh is a predictive biomarker for both MTKI and/or FGFRinh.