Endosonographic features of gastric ectopic pancreases distinguishable from mesenchymal tumors

Background and Aims: Gastric ectopic pancreas is the second common submucosal lesion in the stomach, and differs from mesenchymal tumors with respect to clinical approach and prognosis. The purpose of our study was to evaluate the endoscopic ultrasound (EUS) findings for differentiating between gastric ectopic pancreases and mesenchymal tumors. Methods: All patients (n = 71) were diagnosed pathologically as having gastric ectopic pancreas (n = 18) or mesenchymal tumors (n = 53) between 2002 and 2006. The EUS images of the patients were retrospectively reviewed by two observers who were unaware of the pathological results, regarding location, size, growth pattern, layer of origin, presence or absence of layer disruption, margin, and internal echo pattern. These EUS imaging findings were compared for ectopic pancreases and mesenchymal tumors. Results: Compared with mesenchymal tumors, ectopic pancreases showed a significant difference in the lesion location, growth pattern, layer of origin, presence of layer disruption, margin, and internal echo (P < 0.05). The longest/shortest diameter ratio was also larger in ectopic pancreases (p < 0.05). There was no statistical difference in the lesion size and presence of focal anechoic portion. Conclusion: Careful assessment of the EUS findings may be a useful aid in the differentiation of ectopic pancreases from mesenchymal tumors in the stomach.