Pancreatic intraepithelial neoplasia-3 arising from ectopic pancreas in the jejunum.

摘要

Ectopic pancreas, also called aberrant or heterotopic pancreas, is occasionally observed in areas such as the gastrointestinal tract, biliary duct, liver, spleen, and mediastinum. Ectopic pancreas may show the same pathology with the parent pancreas, such as pancreatitis, cysts, and even malignant transformation. Pancreatic intraepithelial neoplasia (PanIN) as a precursor of invasive pancreatic cancer in the ectopic pancreas has been reported very rarely. PanlNs are thought to progress from flat and papillary lesions without cytologic atypia (PanlN-1A and PanlN-1B), to lesions with full-thickness pseudostratification of nuclei showing mild-to-moderate cytologic atypia (PanlN-2), to lesions showing carcinoma in situ (PanlN-3).1 Malignant transformation of ectopic pancreas in the jejunum is rare, and there have been no reported cases of PanlN-3 in this location.