Boland JM, et al. – This research conducted a clinicopathological and molecular genetic analysis of pulmonary invasive mucinous adenocarcinomas and mixed non–mucinous/mucinous adenocarcinomas. These tumors appeared to be clinically and genetically similar, with the exception of a higher rate of ALK rearrangement in mixed tumors. Similar survival was noted between mucinous tumors and non–mucinous tumors in a non–selected cohort. However, worse survival was reported in a group of smokers enriched for lepidic growth.