Foregut duplication cyst arising in the floor of mouth.

Enteric duplications are uncommon. A rare foregut duplication cyst arising in the floor of mouth is reported. Diagnosis of cystic lesion within the oral cavity was made in utero. Enteric duplications have not yet been attributed to a single embryogenesis but are likely to represent an error in migration of normal cells that rest in an abnormal position. Immediately following delivery of the neonate via an ex-utero intrapartum treatment (EXIT) procedure, the cyst was marsupialised but required definitive surgical excision at 5 weeks of age.