Differential diagnosis: Malignant fibrous histocytoma
, fibrosarcoma, liposarcoma, osteosarcoma, and chondrosarcoma.
Epithelioid sarcoma has many histopathologic mimics, including benign and malignant conditions, such as granuloma annulare, necrobiosis lipoidica, chronic granulomatous inflammation (especially rheumatoid nodules), fibrous histocytoma
, nodular fasciitis, fibromatosis, giant cell tumor of tendon sheath, melanoma, clear-cell sarcoma of the tendon and aponeurosis (amelanotic melanoma of soft part), schwannoma, metastatic squamous cell carcinoma, metastatic adenocarcinoma (especially renal cell carcinoma), synovial sarcoma, epithelioid hemangioendothelioma, epithelioid leiomyosarcoma, and malignant extrarenal rhabdoid tumors of the soft tissue.
These morphological features can mimic other benign or malignant lesions, such as malignant peripheral nerve sheath tumor (MPNST), malignant mesothelioma, sarcomatoid type, monophasic synovial sarcoma, malignant fibrous histocytoma
, fibrosarcoma, leiomyosarcoma, and spindle cell carcinoma.