Adenocarcinoma arising in gastric duplication cyst.

Alimentary tract duplications may occur from the oral cavity to the rectum. The ileocecal valve area is the most commonly affected site.1 Gastric duplication cysts are relatively rare congenital anomalies that constitute only 2% to 8% of alimentary tract duplications.2 These gastric duplication cysts are mostly discovered in children, with most patients presenting during the first year of their life. Associated symptoms often include nausea, vomiting, hematemesis, and abdominal pain.3 Ulceration, bleeding, rupture, and fistula formation are known complications. There have been a few case reports on gastric duplication cysts associated with malignancy.1,2,4,5 Previously reported malignant lesions have included adenocarcinoma, mixed adenocarcinoma and squamous cell carcinoma, and neuroendocrine carcinoma. Here, we report a case of adenocarcinoma arising in a gastric duplication cyst, the first such occurrence to be reported in Korean patients.