The cells are epithelioid with eosinophilic cytoplasm and have rare mitoses; they do not stain S-100, collagen type IV, or nerve growth factor receptor but show reactivity with NK1C3 (CD57) and the panmonocyte marker Ki-M1p.[6] The mixed type of neurothekeoma shows areas of varied cellularity with focal myxoid regions. This evidence concerns the gene B3GAT1 and neurothekeoma.