Gastric duplication cysts expressing carcinoembryonic antigen mimicking cystic pancreatic neoplasms in two adults

Gastric duplication cysts in adults are very rare and usually found incidentally during evaluation for an unrelated ailment. When they are found in close proximity to the pancreas, they can be confused with cystic neoplasms of the pancreas, which are typically also asymptomatic yet more common. As part of the evaluation of cystic pancreatic lesions, cyst fluid analysis for carcinoembryonic antigen (CEA) is undertaken to determine malignant potential. Herein we present two cases of cystic lesions thought to arise from the pancreas found to have elevated preoperative cystic CEA levels. At operation, they were found to be gastric duplication cysts and were resected. We report the histologic findings and review of the current literature.