Malignant peripheral nerve sheath tumors (MPNSTs) are defined as malignant tumors arising from peripheral nerves or differentiating along the line of the elements of the nerve sheath. MPNSTs that originate from the brain parenchyma are exceptionally rare and are termed malignant intracerebral nerve sheath tumors. We experienced a case of the epithelioid variant of malignant intracerebral nerve sheath tumor (MINST) occurring in the right frontal lobe of a 50-year-old man. He underwent gross total resection of the tumor. Histologically, the tumor cells had round, polygonal, or ovoid nuclei and moderate amounts of eosinophilic cytoplasm, which was defined as epithelioid cells. The tumor cells were arranged in short cords or nests with vaguely nodular patterns embedded in the myxoid stroma. Regarding mitotic activity, 15 mitotic figures were noted per 10 high-power fields. Immunohistochemically, tumor cells were positive for S-100 protein and synaptophysin, but negative for glial fibrillary acidic protein, HMB-45, EMA, and AE1/ AE3. Furthermore, immunostaining for INI1 was negative. Loss of the tumor-suppressor gene product SMARCB1/ INI1 expression has been recognized in epithelioid MPNST, but not in conventional MPNST. Postoperatively, he underwent radiotherapy and was followed for almost 1 year without recurrence. The present case is the first report of the epithelioid MINST.

Epithelioid hemangioma is an unusual, which was at first described as angiolymphoid hyperplasia with eosinophilia (ALHE) in 1969 and misinterpreted as the same disease with Kimura’s disease. But now it represents a distinctive vascular tumor, a different entity with those inflammatory conditions. Here, we present a case of epithelioid hemangioma appearing as a diffuse gingival nodular mass in 33‐year‐old male who had suffered from the idiopathic sharp pain of left mandible area previously and later extended to left maxillary region, therefore the gingival lesion was clinically estimated as malignancy associated with neural invasion. CT images revealed the soft tissue mass restricted to left maxillary gingiva without infiltration to underlying maxillary alveolar bone. Histologically, the circumscribed soft tissue mass consist of solid sheets of epithelioid to spindled cells, expressing reactivity for neither cytokeratin AE1/3 nor HMB‐45, but for CD31, endothelial cell marker. Therefore, the lesion was pathologically diagnosed as epithelioid hemangioma. Diagnostic evaluation for the neurologic symptoms of the patient revealed the trigeminal neuralgia, accompanying with the present epithelioid hemangioma incidentally. Awareness of epithelioid hemangioma should be emphasized not to be misdiagnosed as malignant disease like an invasive squamous cell carcinoma, malignant melanoma, or angiosarcoma. Proper evaluation and interpretation for neural symptom may lead to the correct differential diagnosis and therapeutic intervention