Congenital lingual cyst: Expression of MUC protein and report of a new case.

Lingual congenital cysts are uncommon lesions that alter the functions of speech, swallowing and breathing when they have considerable dimension. They usually appear from birth and increase in size gradually in childhood and adolescence. While there are a considerable number of case reports, the nomenclature and origin of this lesion are controversial. Congenital lingual cysts are composed of an epithelial lining that can show heterogeneous histological features, such as globed, ciliated, squamous and parietal cells, while the wall presents mature connective tissue and eventually smooth muscle. In the present manuscript, we report a case of a congenital lingual cyst in a 13-year-old boy, as well as the immunoexpression of MUC family proteins (MUC-1 and MUC-5AC), hoping to provide data that will help to clarify the possible etiology of this lesion.