Retroperitoneal ectopic pancreas: imaging findings.

Ectopic pancreas is relatively uncommon and usually occurs in the stomach or duodenum. Retroperitoneal ectopic pancreas has not previously been documented. We report the case of a 48-year-old man with retroperitoneal ectopic pancreas that imitated bilateral adrenal tumours on ultrasound and MRI. Subsequent CT-guided biopsies confirmed an ectopic pancreas. The lesions remained stable during follow-up for 7 years. In retrospect, the similarity in signal intensities and enhancement pattern between the retroperitoneal masses and the pancreas may have been a clue to the diagnosis of this rare entity.