Will spread through air spaces be a staging parameter in lung cancer?

In the wake of the publication of the multidisciplinary lung adenocarcinoma classification [International Association for the Study of Lung Cancer, American Thoracic Society, European Respiratory Society (IASLC/ATS/ERS)] in 2011 (1), tumor morphology was recognized as a prognostic factor as important as other well-known clinicopathologic features including stage. Patients with lepidic-predominant adenocarcinoma have the most favorable prognosis followed by those with acinar or papillary adenocarcinoma. Those with solid or micropapillary adenocarcinoma have the worst prognosis (2,3).