Necrotizing sialometaplasia: report of five cases.

Necrotizing sialometaplasia (NS) is a self-limiting inflammatory disease, that involves salivary glands, more frequently the minor ones. Although its etiopathogenesis remains still unknown some authors suggest that a physico-chemical or biological injury on the blood vessels may produce ischemic changes, leading to infarction of the gland and its further necrosis. Its clinical and histologic feature resemble malignancy. Clinically it may appear like an ulcer with slightly elevated irregular borders and necrotic base. Histologic features are squamous metaplasia of ducts and acini and a pseudoepitheliomatous hyperplasia of the overlying mucosa. These characteristics may induce to an inapropiated diagnosis of malignant neoplasia. A correct diagnosis to avoid mutilant surgical treatments is essential, considering that it is a self-limiting disease. In this report we describe five cases of NS in females, located in minor glands of the palate.