Epithelioid soft tissue tumors.

Epithelioid neoplasms are generally carcinomas. As confirmation that every rule is meant to be broken, some sarcomas demonstrate epithelioid morphology, and can even express cytokeratins. These sarcomas have unique behavior, for example, a much higher rate of lymph node metastasis than other sarcomas. This group of sarcomas also presents diagnostic and therapeutic challenges to those clinicians who help patients contend with these difficult tumors. In this review, some of the major categories of epithelioid soft tissue tumors are described, with clinical data reported as available. Some of these tumors provide excellent opportunities to examine newer protein-targeted agents in investigational settings.