Cystic lymphoepithelial lesions of the pancreas and peripancreatic region:Report of two cases

Two cases of an extremely rare cystic lymphoepithelial lesion of a lymph no de associated with the pancreas are presented herein. The first patient was a 57-year-old woman with a serous cystoadenoma who underwent resection of the body and tail of pancreas, and the other patient was a 75-year-old woma n with cancer of the papilla of Vater who underwent pylorus-preserving panc reatoduodenectomy. Both lesions were incidentally found during pathologic e xamination of lymph nodes from the peripancreatic region. Histologically, t here were many scattered nests of the lymphoepithelial lesion in the lympho id stroma, each of which was lined with stratified squamous epithelium. The pathological structure was found to resemble the lymphoepithelial lesion o f the pancreas. Although the histogenesis is unknown, we hypothesize that t he lesion might have arisen from squamous metaplasia of a benign epithelial inclusion such as the pancreatic duct of an ectopic pancreas in a peripanc reatic lymph node. Therefore, a cystic lesion formed as a result of keratin ization of the squamous epithelium with invasion into the pancreas could be come a lymphoepithelial cyst of the pancreas.