Benign epithelioid schwannoma is a very rare variant of schwannoma, that can pose a diagnostic challenge. The reported cases were predominantly located in dermal/subcutaneous tissue. Although conventional schwannoma occurring in the posterior mediastinum was common, to our knowledge, no mediastinal benign epi-thelioid schwannoma was reported in English literature. Herein, we presented a case of mediastinal benign epithe-lioid schwannoma in a 50-year-old Chinese male. Histologically, the tumor

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... s well encapsulated and consisted of sheets of epithelioid tumor cells with mild cellular atypia set in fibrous or myxoid stroma. Immunohistochemically, the tumor cells were positive for S-100, GFAP and Vimentin, negative for cytokeratin, EMA, P63, Actin (SM), CD3, CD20, CD30, CD31, CD34, cytokeratin19, HMB45, CD68 and Desmin. Ki-67 proliferation index was approximately 2%. Based on morphologic features and the immunohistochemical staining, the tumor was diagnosed as an epithe-lioid schwannoma. It should be noted that epithelioid schwannoma may be also an important differential diagnosis in mediastinal tumor.