Foregut duplication cyst of the stomach is rare. Foregut duplications may or may not communicate with the gastrointestinal tract, and are usually diagnosed at a young age. There have been relatively few case reports describing this entity. Adenocarcinoma has been reported in four cases of gastric duplication cyst, but not in cysts that have a ciliated epithelium. Controversy exists concerning the embryological origin of these anomalies.
A research article to be published on January 7, 2011 in the World Journal of Gastroenterology addresses this question. The authors presented two cases of gastric ciliated duplication cyst with emphasis on immunophenotype and embryogenesis.
Two cases showed that the cysts are lined with a pseudostratified respiratory epithelium with ciliated cells, which express thyroid transcription factor-1 and surfactant. This suggests an origin from the respiratory diverticulum, which arises from the ventral foregut and could also explain why these cysts do or do not maintain their connection to the gastrointestinal tract.
Further research is required to explore the proposed mechanism. Better understanding of the embryogenesis of these lesions could lead to early diagnosis or even prevention.