Cysts result from obstruction to the ducts of the mucous or salivary glands. A ranula is a cystic dilatation of Nuhn's glands situated under the tip of the tongue, which may be displaced backward and upward. A thick viscid fluid fills the cavity. Dermoid cysts are also found.

Macroglossia, thickening of the tongue, and macrochilia, thickening of the lips, result from a lymphangioma. The lymphatic spaces are much distended and contain liquid and round cells. This condition is generally congenital, the result of thyroid deficiency; is met with in cretins.