Comprehensive Molecular and Clinicopathologic Analysis of 200 Pulmonary Invasive Mucinous Adenocarcinomas Identifies Distinct Characteristics of Molecular Subtypes

Abstract

This is the largest molecular study of IMAs to date, where we demonstrate the presence of a major oncogenic driver in nearly all cases. This study is the first to document more aggressive characteristics of <i>NRG1</i>-rearranged IMAs, <i>ERBB2</i> as the third most common alteration, and a novel <i>NRG2</i> fusion in these tumors. Comprehensive molecular testing of <i>KRAS</i> wild-type IMAs that includes fusion testing is essential, given the high prevalence of alterations with established and investigational targeted therapies in this subset.