A Study of Prevalence of HER3 Expression in Non-Small Cell Lung Cancer

The purpose of this study is to use archival tissue samples and RW data to generate HER3 expression prevalence data within the NSCLC population and by patient characteristics (e.g., ethnicity, histology, smoking status, age, prior treatment, etc.). The primary objective of the study will analyze and assess archival tissue specimens and associated RW data to: * Increase the understanding of HER3 expression in NSCLC among HCPs and the medical community * Generate evidence to support future clinical strategies in this area