Localized amyloidosis of the tongue: a review.

Amyloidosis is a disease entity defined by the presence of extracellular deposits of proteinacious material. These deposits have a characteristic apple-green birefringence with polarized light after staining with Congo red. Amyloid involvement of the tongue is almost universally secondary to systemic disease. The mean survival of patients with a systemic form of amyloidosis is between 5 to 15 months, whereas those with the localized form have an excellent prognosis. This article presents a case of the more unusual localized form. A thorough evaluation, including abdominal fat or rectal biopsy, is essential in every patient to identify any systemic involvement. The absence of systemic amyloidosis offers a much more favorable prognosis and may be treated with simple surgical excision.