HER2 Mutation and Response to Trastuzumab Therapy in Non–Small-Cell Lung Cancer

Abstract

To the Editor: Trastuzumab is a monoclonal antibody against HER2, a member of the epidermal growth factor receptor (EGFR) family, that improves the outcome of HER2-positive breast cancer.1 Preclinical data have demonstrated that trastuzumab is effective in non–small-cell lung cancer, with additive or synergistic effects with various cytotoxic agents. However, trials of trastuzumab or other HER2-targeted agents, such as pertuzumab, failed to demonstrate clinical benefit in non–small-cell lung cancer when administered as monotherapy or combined with chemotherapy.2 In these studies, HER2 status was assessed by immunohistochemical analysis, a method that is not optimal.3 Moreover, the few patients whose tumors had . . .