Intramuscular lipoma of the tongue

Purpose: Although lipomas are the most common neoplasms of the soft tissue; they are only presenting 1 to 5 percent of all of the benign neoplasms of the oral cavity. Oral lipomas affect predominantly the buccal mucosa, floor of mouth, tongue and lips. Intramuscular (infiltrating) lipoma of the tongue is an extremely rare variant of lipoma and a few cases have been reported until now. Case: A 50-year-old woman, who had exophytic, painless lesion on the right lateral border of the tongue, has gone to surgery for excision. Macroscopically, the mass was polypoid, had a soft consistency and measured 0.6x0.5x0.2 cm. Microscopic examination of the haematoxyilin-eosin stained sections showed intact squamous epithelium over the surface. The submucosa revealed adipocytes, which lie down through the skeletal muscle fibers and extend to the epithelial level. Conclusion: When a painless, slow growing, well demarcated lesion occur on the tongue, although it is uncommon, one must remember intramuscular lipomas. Although until now a few cases have been reported, with the same histological and clinical appearance, well-differentiated liposarcoma must be excluded and surgical excision should be carefully done.