Lymphoepithelial cyst of the pancreas: a preoperatively diagnosed case based on an aspiration biopsy

This paper reports an extremely rare case of lymphoepithelial cyst of the pancreas. The patient, a 58-year-old man with no subjective symptoms, was found to have a pancreatic tumor during a physical examination. He visited our clinic and was admitted for a follow-up examination. Based on the ultrasonographic findings, superselective angiography, and aspiration biopsy, an epidermoid cyst was diagnosed. Enucleation was easily performed. Macroscopically, this cyst resembled an atheroma. Histologically, the cavity of the cyst was lined with a squamous epithelium with a nucleated layer and below that, lymphatic tissue. No malignancy was found. Tumors of the pancreas with a squamous epithelial covering are extremely rare; only a few such cases have been reported in the literature. As of 1991, only 12 cases, including the present case, had been reported. With the advances in diagnostic techniques, the detection of pancreatic tumors is expected to improve. This paper reports a case in which the use of an aspiration biopsy and superselective angiography proved to be useful in making an accurate diagnosis.