[Lymphoepithelial cyst of the pancreas: a new case report]. / Le kyste lymphoépithélial du pancréas : à propos d'un nouveau cas.

We report the case of a lymphoepithelial cyst of the pancreas discovered by chance on imaging in a 54-year old man. CT-scan showed a 10 cm hypodense multilocular cystic tumor of the pancreatic isthmus. Fine-needle aspiration did not provide further information. Due to the lack of preoperative diagnosis and mostly because it was not known if the cyst was malignant or benign, the patient underwent a cephalic duodenopancreatectomy. Lymphoepithelial cyst of the pancreas is a rare benign lesion which is difficult to diagnose before surgery. Histologically, the cyst wall is lined by mature keratinizing squamous epithelium and a distinct surrounding lymphoid tissue layer. The cysts are filled with keratin plugs that are not always visualized on imaging. Cytological and histological analysis of fine-needle aspiration material if the sample material is sufficient may help avoid extensive surgery.