Epithelioid Lesions.

Epithelioid variants have been described for most mesenchymal tumors, including leiomyosarcoma, pleomorphic liposarcoma, epithelioid fibrous histiocytoma, and myxofibrosarcoma. Soft tissue tumors that commonly show epithelioid morphology include epithelioid vascular lesions, epithelioid sarcoma, sclerosing epithelioid fibrosarcoma, and epithelioid malignant peripheral nerve sheath tumor. Many of the entities described in this review were originally described as "simulating carcinoma" or "often mistaken for carcinoma" and this pitfall should be considered when evaluating epithelioid lesions in soft tissue. Many epithelioid soft tissue tumors express epithelial antigens to a varying degree and an immunohistochemical panel is essential for correct classification.