MA14.07 EGFR-Mutant NSCLC With de novo or Acquired Squamous Histology: Molecular Features and Clinical Outcomes

Abstract

Activating EGFR mutations occur predominantly in lung cancers with adenocarcinoma histology but can rarely be found in squamous tumors. Histologic “transformation” from adenocarcinoma to squamous is also seen at acquired resistance to EGFR TKIs. While squamous transformation may potentially be a driver of resistance, the biological characteristics of and treatment recommendations for squamous histology in the setting of EGFR-mutant NSCLC remain incompletely understood.