Concordant and Discordant EGFR Mutations in Patients With Multifocal Adenocarcinomas: Implications for EGFR-Targeted Therapy

Our findings suggest that the emergence of the dominant EGFR driver alteration is often independent between lesions in patients with multifocal adenocarcinomas, and thus the same targeted therapy may not be effective for all lesions. However, genetic testing of multiple lesions can help to distinguish separate primary tumors from metastatic disease.