c-MET as a Potential Resistance Mechanism to Everolimus in Breast Cancer: From a Case Report to Patient Cohort Analysis.

Background: We describe in a patient with breast cancer the change in c-MET expression during everolimus treatment, opening a better understanding of the resistance to everolimus and a role for cabozantinib.

Objective: The objective of this study was to evaluate c-MET as a potential predictive biomarker for everolimus efficacy in breast cancer.

Methods: We first selected a patient with breast cancer with a long-lasting response to everolimus and retrospectively profiled biopsies that were taken before everolimus initiation (Biopsy 1) and at progression on everolimus (Biopsy 2) using amplicon sequencing and immunohistochemistry.