Gastric aberrant pancreas: EUS analysis in comparison with the histology

Background: Histologic diagnosis of aberrant pancreas is usually difficult when tissue samples are obtained with a standard biopsy forceps. The aim of this study was to describe the endosonographic (EUS) features of gastric aberrant pancreas. Methods: EUS was performed in 10 patients with aberrant pancreas before resection, EUS features of the lesions were analyzed and compared with resected specimens retrospectively. Results: EUS in 5 lesions (50%) demonstrated the ectopic pancreatic tissue as located in the third and fourth sonographic layers (submucosa and muscularis propria) and in the third layer (submucosa) in the other 5 lesions. The margin appeared for the most part indistinct (80%) because of the lobular structure of the acinous tissue. The internal echo pattern in all cases was heterogeneous, mainly a hypoechoic image (acinous tissue) accompanied by scattered small hyperechoic areas (adipose tissue). An anechoic area (duct dilatation) (80%) and fourth-layer thickening (muscular hypertrophy) (80%) were commonly visualized. Conclusion: Gastric aberrant pancreas has characteristic EUS features that correlate with specific histologic components and is variable with regard to sonographic layer of origin.