Non-Small Cell Lung Cancer: Rare Types

The 2015 World Health Organization classification of malignant lung tumors includes broad categories of common and uncommon lesions with different histological features. While the common types of non-small-cell lung cancer (NSCLC) are well known, there are other types of NSCLC that are less common and seldom encountered in the clinical routine. Sarcomatoid, salivary gland-type, and other/unclassified carcinomas are included in rare epithelial entities. In addition to uncommon epithelial lung cancer, other malignant pulmonary lesions of mesenchymal or lymphoid origin have a certain clinical and radiological interest. The most interesting histotypes included in the mesenchymal and lymphoid groups are epithelioid hemangioendothelioma, synovial sarcoma, pulmonary artery intimal sarcoma, and mucosa-associated lymphoid tissue lymphoma.