Validation of the new IASLC/ATS/ERS lung adenocarcinoma classification: a surgeon’s perspective

The recently introduced new classification of lung adenocarcinoma has a relevance which goes beyond the features of an updated histological perspective on a lung cancer histotype (1). The primum movens of this new classification was to overcome the concept of bronchoalveolar carcinoma which had been known to portend a better prognostic outlook compared to other types of adenocarcinomas (1). At the same time, the resurgence of interest for radiologically detected lesions characterized by ground glass appearance and a non predominant solid component has raised the question about how to best manage these lesions (1). Screening programs will contribute to earlier detection of lung cancer and possible identification of GGOs which would have otherwise gone undetected or be mistakenly diagnosed as of inflammatory origin (2). Finally, the tumor genomic era has brought about the so called “oncogenic addiction”, i.e., the focus on genetic mutations as the main driver of phenotypic changes of lung tumors. In this setting, the relevance of biomarkers as predictors of response to treatment has become a guiding principle in current clinical research on adenocarcinoma