Sarcomatoid carcinoma of the lung. A case with atypical carcinoid and rhabdomyosarcomatous components

Sarcomatoid carcinomas of the lung are uncommon malignant biphasic tumors composed of carcinomatous and sarcomatous components. The carcinomatous component is usually a squamous carcinoma, and the sarcomatous component usually resembles a fibrosarcoma or a malignant fibrous histiocytoma. The presence of rhabdomyoblastic differentiation in such neoplasms is exceedingly rare, with only seven documented cases. This report describes a unique case of sarcomatoid carcinoma in a 52-year-old woman in whom the sarcomatous component of the tumor was a rhabdomyosarcoma and the carcinomatous component was an atypical carcinoid. The authors know of no previous report of a sarcomatoid carcinoma of the lung in which the carcinomatous component is a carcinoid.