Microscopically, EMECL features bi-layered glandular or ductular structures consisting of inner cuboidal cells and outer multipolar cells. The histologic appearance of these tumors varied, but all shared the common feature of a biphasic proliferation of<unk>  (strong cytokeratin-positive; actin and S-100-negative) and<unk>  (strong actin and S-100 and focal weak cytokeratin-positive) cells with formation of bilayered ductlike structures. The focal resemblance to other salivary gland-type tumors may cause diagnostic difficulties, particularly in small endobronchial biopsies. Although little is known about their biologic potential due to limited follow-up data, these tumors when in the lung clearly have the capacity to infiltrate and metastasize and therefore should be designated as<unk><unk>  carcinoma. At present, it appears that treatment by complete surgical resection with negative margins alone is appropriate and adequate. Classification Lung cancer is an extremely heterogeneous family of malignant neoplasms, with well over 50 different histological variants recognized under the 4th revision of the World Health Organization (WHO) typing system ("WHO-2004"), currently the most widely used lung cancer classification scheme. Because these variants have differing genetic, biological, and clinical properties, including response to treatment, correct classification of lung cancer cases are necessary to assure that lung cancer patients receive optimum management. The WHO-2004 scheme groups lung carcinomas into 8 major types: * Squamous cell carcinoma * Small cell carcinoma * Adenocarcinoma * Large cell carcinoma * Adenosquamous carcinoma * Sarcomatoid carcinoma * Carcinoid tumor * Salivary gland-like carcinoma EMECL is considered a subtype of salivary gland-like carcinoma, tumors so named because their histological appearance and characteristics closely resemble malignant neoplasms arising in the major and minor salivary glands. Staging EMECL is staged in the same manner as other non-small cell lung carcinomas, based on the TNM (Tumor-Node-Metastasis) staging system.
Epithelial-myoepithelial carcinoma of the lung
Salivary gland–like carcinoma of the lung
Mucinous cystadenocarcinoma of the lung
Giant-cell carcinoma of the lung
Sarcomatoid carcinoma of the lung
Pulmonary sclerosing pneumocytoma
Combined small-cell lung carcinoma
Adenosquamous lung carcinoma