Heterotopic pancreas: a clinicopathological study of 184 cases from a single high-volume medical center in China.

Heterotopic pancreas (HP) is often an incidental finding during operative or endoscopic procedures and described in case reports and small series in the literature. Large clinicopathological studies with a systematic analysis remain lacking. Herein, we identified 184 (0.18%; 184/99 544) consecutive histology-proven HP cases of 89 770 surgical resections and 9774 upper endoscopic biopsies carried out at a single medical center in China. Each case was diagnosed by unequivocal identification of pancreatic acini at a location outside the pancreas. The patients' median age was 49 years (range, 14-82) with a slight female predominance (male/female ratio, 0.94). Clinical presentation at diagnosis was nonspecific. Preoperatively, most (54.9%; 101/184) HP lesions were misdiagnosed. Only 26 HP lesions (14.1%) were correctly diagnosed, all in the stomach except for 1 in the duodenum; 57 (31%) were detected during operative procedures for other conditions. The most frequent location of HP was, in descending order, the stomach (97; 52.7%), small intestine (48; 26%), lesser and greater curvature omentum (18; 10%), spleen and hilar region (5; 2.7%), porta hepatis (2; 1%), gallbladder (1; 0.5%), peridistal esophageal tissue (4; 2.2%), and mesentery (7; 3.8%). The size of HP varied from smaller than 0.5 cm (35.3%), 0.6 to 1 cm (34.8%), to larger than 1.1 cm (29.9%). Because of difficulty in preoperative diagnosis, careful workup for upper gastrointestinal diseases with HP as a differential diagnosis may increase the chance of accurate diagnosis and appropriate patient management.