These tumour cells are immunohistochemically positive for S-100 protein (supporting the neural origin of granular cell tumour), as well as for neuron-specific enolase, CD68, calretinin, CD57, inhibin, TFE3, SOX, CD59, PGP9.5, and vimentin [7, 14, 15]. The gene discussed is B3GAT1; the disease is neoplasm.