[Lympho-epithelial cyst of the pancreas: a difficult diagnosis. About two cases].

We report two cases of lymphoepithelial cyst of the pancreas discovered incidentally on imaging in two men aged 50 and 61 years. One cyst contained hyperdense spots on CT-scan and in this case the biochemical analysis of the cyst fluid revealed high level of CEA. The unilocular cysts measured 4 and 5 cm on the surgical specimen. On microscopic examination, the cysts were lined by squamous keratinized epithelium positive for CEA, with rare mucin-secreting cells, lining on lymphoid tissue. The lymphoepithelial cyst is a rare dysembryoplastic benign lesion of the pancreas difficult to diagnose before surgery. The presence of keratin plugs on imaging is inconstant and the biochemical analysis of the cyst fluid can mislead to a diagnosis of mucinous cystic tumour. Cytological and histological analysis of fine needle aspiration material is of diagnostic interest and can avoid surgical resection when patients are symptom-free.