DES and mesothelioma: The differential diagnosis of DSRCT can be with a variety of other round-cell tumors, including Ewing sarcoma, rhabdomyosarcoma, small-cell carcinoma, and mesothelioma.21,22) In most cases of DSRCT, the expression of Desmin, Cytokeratin (CK), Epithelial membrane antigen (EMA), and vimentin is positive.