FREDERIC B.ASKINMDWILLIAM H.WESTRAMD
Sarcomatoid carcinomas of the larynx are unusual and distinctive malignant neoplasms that exhibit mixed carcinomatous and sarcomatous features. This mixed phenotypic presentation is now explained as being due to phenotypic divergence from a common progenitor cell.1 Neoplasms with mixed epithelial and mesenchymal features have been recognized since the time of Virchow.2 Though rare, sarcomatoid carcinomas have been well described and have been noted to occur in various body sites, including the upper and lower respiratory tracts, breasts, skin, urogenital tract, salivary glands, and gastrointestinal tract. Multiple synonyms, including spindle cell carcinoma, pleomorphic carcinoma, pseudosarcoma, and carcinosarcoma, have been used to describe these tumors. This disparity of names is evidence of the history of the pathogenetic theories that have evolved over time. Different theories have speculated that the sarcomatoid carcinoma is (1) a "collision tumor" in which 2 distinct malignant neoplasms, ie, sarcoma and carcinoma, collide and intermingle, thus giving rise to the name carcinosarcoma; (2) a carcinoma associated with an exuberant but benign sarcomalike spindle cell connective tissue reaction induced by the adjacent carcinoma, thus leading to the name pseudosarcoma; and (3) a tumor of epithelial origin that "dedifferentiates" or transforms into a spindle cell variant. The latter is the most widely accepted theory, especially for upper respiratory tract sarcomatoid carcinomas.
Pathology Quiz Case—Diagnosis. Arch Otolaryngol Head Neck Surg. 2003;129(11):1244-1245. doi:10.1001/archotol.129.11.1243