Perianal granular cell tumor: report of a case and review of the literature.

INTRODUCTION Granular cell tumor was first described by Abrikossoff in 1926. Over the years several cases of this neoplasm have been reported, with a variety of localizations. We here report a case of perianal granular cell tumor and discuss its histogenesis and its relevance to clinical practice. METHODS The clinical course and histopathology of the case are reviewed, and a literature search for other reported cases has been performed. RESULTS A 46-year-old woman presented with a perianal nodular lesion. Pathological examination revealed a granular cell tumor. A literature search produced only 25 other cases of anal and perianal granular cell tumors. CONCLUSIONS Granular cell tumors are rarely observed in the perianal region. Their existence must always be borne in mind in the differential diagnosis of perianal neoplasms. In most cases surgical excision is curative, but potential malignant transformation must be considered during therapeutic procedures and follow-up.