title: Lymphoepithelial cyst with sebaceous glands of the pancreas: a case report.
abstract: BACKGROUND
  Lymphoepithelial cyst (LEC) of the pancreas is a rare benign tumor. LEC with sebaceous glands of the pancreas is extremely rare, and its histogenesis remains unclear.
  
  
  METHODS
  We present a 66-year-old man with an incidental finding of a cystic lesion at the neck of the pancreas. Pancreatic juice cytology results and elevated serum carbohydrate antigen 19-9 and Dupan-2 levels indicated that the cyst was a potential adenocarcinoma. Therefore, a pancreaticoduodenectomy was performed. Macroscopically, the tumor was a unilocular cyst with a thin transparent wall, filled with soft yellow material. Pathological findings showed that the cyst was lined with squamous epithelium, accompanied by dense lymphoid tissue with scattered germinal centers. There were no hair follicles, but sebaceous glands were present in the lymphoid tissue just beneath the squamous epithelium. Therefore, the histopathological diagnosis was an LEC with sebaceous glands of the pancreas. Furthermore, the squamous epithelium surrounding the cyst was pathologically continuous with the tubular structure, indicating that the tubular structure transitioned into the squamous epithelium.
  
  
  CONCLUSIONS
  We report an extremely rare case of LEC with sebaceous glands of the pancreas. Moreover, the pathological findings, which showed that the tubular structure transitioned into the squamous epithelium, suggested that this was squamous metaplasia. In order to investigate the histogenesis of LEC of the pancreas, the pathological findings must be evaluated.
authors.affiliation: Department of Surgery, Shiga University of Medical Science, Seta-tsukinowacho, Otsu, Shiga, 520-2192, Japan. hiro0103@belle.shiga-med.ac.jp.
authors.forename: Hiromitsu
authors.identifier: http://orcid.org/0000-0003-3064-5216
authors.initials: H
authors.lastname: Maehira
authors.affiliation: Department of Surgery, Shiga University of Medical Science, Seta-tsukinowacho, Otsu, Shiga, 520-2192, Japan.
authors.forename: Hisanori
authors.initials: H
authors.lastname: Shiomi
authors.affiliation: Department of Surgery, Shiga University of Medical Science, Seta-tsukinowacho, Otsu, Shiga, 520-2192, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Murakami
authors.affiliation: Department of Surgery, Shiga University of Medical Science, Seta-tsukinowacho, Otsu, Shiga, 520-2192, Japan.
authors.forename: Hiroya
authors.initials: H
authors.lastname: Akabori
authors.affiliation: Department of Surgery, Shiga University of Medical Science, Seta-tsukinowacho, Otsu, Shiga, 520-2192, Japan.
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Naka
authors.affiliation: Department of Clinical Sciences and Laboratory Medicine, Kansai Medical University, Osaka, Japan.
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Ishida
authors.affiliation: Department of Surgery, Shiga University of Medical Science, Seta-tsukinowacho, Otsu, Shiga, 520-2192, Japan.
authors.forename: Masaji
authors.initials: M
authors.lastname: Tani
keywords: Histogenesis; Lymphoepithelial cyst; Sebaceous gland