Sporadic oral angiomyolipoma. Case report.

Angiomyolipoma (AML) is a rare, benign tumour composed of a variable proportion of lipocytes, smooth muscle and thick-walled blood vessels. AML is part of a family of tumours arising from perivascular epithelioid cells (PEComas), and many cases are associated with tuberous sclerosis, with the kidney being the most frequent site involved. We report a case of sporadic AML in the hard palate of a 52-year-old male, an extremely unusual location for this tumour. Differentiation from other benign and malignant oral mesenchymal lesions depends on recognition of the three histologic components, and immunohistochemical techniques may be helpful. AML occurring in the head and neck do not express HMB-45, an antibody that identifies immature melanosomes, conversely to the usual immunopositivity shown in AMLs from kidney and liver, suggesting that there are differences among them. A wide surgical excision is considered curative, as this tumour usually behaves in a benign fashion.