title: The World Health Organization. Histological typing of lung tumours.
abstract: The WHO Histological Classification of Lung Tumours, published in 1967, has been revised. The main features are as follows: Squamous cell carcinoma (epidermoid carcinoma) has the same definition as in the original version, i. e., the identification of keratin and/or intercellular bridges by light microscopy. Three degrees of histological differentiation are described. Dysplasia and carcinoma in situ are discussed. Small cell carcinoma is divided into oat-cell carcinoma, an intermediate cell type and a category for oat-cell carcinomas combined with other major typed, Adenocarcinoma includes the acinar, papillary and bronchiolo-alveolar forms and the solid carcinomas with mucus formation (previously part of the large cell carcinoma group). Mesothelial tumours are divided into fibrous, epithelial and biphasic subtypes. A number of less common tumours and tumour-like lesions are defined.
mesh_terms: D000230:Adenocarcinoma / Q000145:classification; D002278:Carcinoma in Situ / Q000145:classification; D018288:Carcinoma, Small Cell / Q000145:classification; D002294:Carcinoma, Squamous Cell / Q000145:classification; D006801:Humans; D008175:Lung Neoplasms / Q000145:classification*; D014944:World Health Organization