Bronchogenic cyst of the stomach: A case report.

Background: Gastric bronchogenic cysts (BCs) are extremely rare cystic masses caused by abnormal development of the respiratory system during the embryonic period. Gastric bronchial cysts are rare lesions first reported in 1956; as of 2019, only 37 cases are available in the MEDLINE/PubMed online databases. BCs usually have no clinical symptoms in the early stage, and their imaging findings also lack specificity. Therefore, they are difficult to diagnose before histopathological examination.

Case Summary: A 55-year-old woman presented at our hospital with intermittent epigastric pain. She had a slightly high level of serum carbohydrate antigen 72-4 (CA 72-4). Endoscopic ultrasound found that a cystic mass originated from the submucosa of the posterior gastric wall near the cardia, indicating a diagnosis of cystic hygroma of the stomach. Furthermore, a computed tomography scan demonstrated a quasi-circular cystic mass closely related to the lesser curvature of the gastric fundus with a low density. Because the imaging examinations did not suggest a malignancy and the patient required complete resection, she underwent laparoscopic surgery. As an intraoperative finding, this cystic lesion was located in the posterior wall of the fundus and contained some yellow viscous liquid. Finally, the pathologists verified that the cyst in the fundus was a gastric BC. The patient recovered well with normal CA 72-4 levels, and her course was uneventful at 10 mo.

Conclusion: This is a valuable report as it describes an extremely rare case of gastric BC. Moreover, this is the first case of BC to present with elevated CA 72-4 levels.