title: Carcinoma of the colon with undifferentiated, carcinoid, and squamous cell features.
abstract: An undifferentiated small cell tumor of the colon that was found by light- and electron-microscopic study to possess features of a malignant carcinoid merged into keratinizing squamous cell carcinoma. Single cells contained both dense-core secretory granules and tonofilaments. The implications of this combination in relation to theories of tumor origin and differentiation are briefly discussed.
mesh_terms: D000368:Aged; D002276:Carcinoid Tumor / Q000473:pathology*; D018288:Carcinoma, Small Cell / Q000473:pathology*; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D003110:Colonic Neoplasms / Q000473:pathology*; D006801:Humans; D008297:Male