Adenomatoid hyperplasia of the upper lip

OBJECTIVES: The aim of the present article was to report a rare case of bilateral adenomatoid hyperplasia of minor salivary glands of the upper lip.

MATERIALS AND METHODS: Adenomatoid hyperplasia of minor salivary glands is a rare condition characterized by a benign, nonneoplastic enlargement of minor mucous salivary glands. Clinically, the lesion may be misdiagnosed as a salivary gland neoplasm or fibroma, but histological examination shows that there are usually more aggregates of normal-appearing salivary glands than are anticipated
expected at that for the anatomical site. Pathogenesis is not clear, although a reactive hyperplasia to chronic trauma, such as in presence of ill-fitting complete dentures, has been suggested. Adenomatoid hyperplasia is considered an idiopathic, focal hypertrophic lesion of the minor salivary glands. Some authors consider it a developmental variation (hamartoma). Most cases of adenomatoid hyperplasia were reported to occur in the palate.

RESULTS AND DISCUSSION: A 24-year-old man presented with a history of a bilateral swelling of the lips for 2 years. The lesion was painless and had progressively increased in size. There was no previous trauma or contributory medical history. On physical examination there was a bilateral ill-defined mass affecting the upper lip.

CONCLUSIONS: Adenomatoid hyperplasia is a rare entity in correspondence of the lip and it should be considered in the differential diagnosis of mucocele and other non-neoplastic and neoplastic lesions of minor salivary glands.

CLINICAL SIGNIFICANCE: Histopathological findings are fundamental to obtain a definitive diagnosis.