RESUMO
BACKGROUND: Abrikossoff or granular cell tumour (GCT) is a relatively rare neoplasia, benign in most of the cases. It may occur in any part of the human body, but it has an oral location in 70% of the cases. Its origin has been discussed for decades, and it is not yet definitively determined. Immunohistochemical techniques suggest its origin in the Schwann cells, while more recent studies with new markers indicate an origin related to neuroendocrine cells. OBJECTIVE: Contribute to the clarification of histogenesis of oral Abrikossoff tumour studying immunohistochemical marking of 11 oral Brazilian cases. MATERIALS AND METHODS: Samples of tissues from the oral mucosa, tongue and lips placed in paraffin blocks, from eleven patients with a histopathological diagnosis of benign GCT were studied. Four different anti-serums (S-100, vimentin, PGP9.5 and ENE) were used for immunoperoxydase technique. RESULTS: A clear positivity for S-100 protein and vimentin was observed, with markers indicating origin from the Schwann cells. Less intense positivity was found in some cases, for ENE and PGP9.5, which suggests a neuroendocrine origin. CONCLUSIONS: The results obtained suggest an origin from Schwann cells, but also arise the possibility of neuroendocrine origin. New methods and more specific immunohistochemical markers are needed to elucidate the origin of the Abrikossoff tumour.