Unique presentation of heterotopic pancreatic tissue arising from small-bowel mesentery

Heterotopic pancreatic tissue in the small-bowel mesentery is an extremely rare anomaly: no such case has been reported in the English literature. We report a 5-year-old boy in whom the aberrant tissue formed a retroperitoneal cyst. The condition was further complicated by a ventral pancreatic duct defect. The unique clinical manifestations and difficulty in making the diagnosis are discussed.