This text consists of neoplastic and non-neoplastic lung pathology. It discusses frequently encountered issues and diagnostic problems using a Q&A format and case presentations.  Emphasis is placed on differentiating one from another based on the histopathological features, ancillary tests including immunohistochemical and molecular analyses, and clinical and radiologic correlation. In particular, clinical-radiologic-pathologic correlation is emphasized in the diagnosis of interstitial lung disease (ILD).This text addresses the issues and diagnostic criteria in segregating a reactive process...