Adenocarcinoma arising from colonic duplication cyst with metastasis to omentum: A case report.

Gastrointestinal tract duplications are uncommon congenital abnormalities. Carcinoma arising from duplication cyst is extremely rare, not to mention metastasis to other organs. We present a case of adenocarcinoma arising from a colonic duplication cyst with invasion of the serosa and metastasis to the omentum in a 40-year-old man. Duplication cysts should be included in the differential diagnosis of cystic masses of the gastrointestinal tract. Because these lesions occur so infrequently, they are often not suspected until encountered intraoperatively. The specific findings and advantages of sonography are reviewed.