Concomitant Congenital Intraoral Dermoid Cyst and Heterotopic Gastrointestinal Cyst.

Sublingual dermoid cysts and oral heterotopic gastrointestinal cysts are well-documented causes of sublingual swellings in infants. However, the simultaneous occurrence of both cysts is an extremely rare phenomenon, with only two previous cases reported in literature. We present a case of 1-month-old neonate with a cystic ventral tongue mass that on histologic examination showed a dermoid cyst with co-existing heterotopic gastric-type epithelium in the wall. Additional histochemical stains revealed focal areas of colonic metaplasia within the heterotopic gastric epithelium. CDX2 immunohistochemical staining confirmed derivation from colonic epithelium.