Cytologic features of lymphoepithelial cyst of the pancreas: two preoperatively diagnosed cases based on fine-needle aspiration.

We describe the cytologic features seen in fine-needle aspiration (FNA) specimens from two cases of preoperatively diagnosed lymphoepithelial cyst (LEC) of the pancreas. Pancreatic LEC is a rare, true cyst of uncertain histogenesis that may clinically and radiologically mimic a pseudocyst or cystic neoplasm. Both our patients were middle-aged men who presented with vague abdominal pain. Computed tomography (CT) of the abdomen revealed a mass in or around the pancreas, and CT-guided percutaneous FNA (patient 1) and endoscopic ultrasound-guided FNA (patient 2) yielded paste-like yellow-gray material. Cytologic smears showed numerous anucleated squamous cells in a background of keratinous and amorphous debris. A few benign nucleated squamous cells and plate-like cholesterol crystals were also seen. Unlike LEC of the head and neck region, only rare lymphocytes and histiocytes were present. Pancreatic LEC was diagnosed based on these cytologic findings and was histologically confirmed following cyst enucleation (patient 1) and partial pancreatectomy (patient 2). We conclude that preoperative FNA and recognition of the characteristic cytologic pattern will enable conservative surgical management of pancreatic LEC. Diagn. Cytopathol. 1999;21:346-350. Copyright 1999 Wiley-Liss, Inc.