Pancreatic Lymphoepithelial Cyst Showing Multiple Floating Ball-like Appearances

Abstract

A lymphoepithelial cyst (LEC) is a rare pancreatic lesion, histologically showing squamous epithelia, dense lymphoid tissues, and a keratin substance. Cross-section images of the pancreatic LEC typically show a well demarcated unilocular or multilocular cyst without a solid component. Here we report a rare case of pancreatic LEC in which multiple floating ball-like components were depicted via endoscopic ultrasound. The ball-like components were also depicted by various imaging methods such as computed tomography (CT) showing low-density components, T1-weighted magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) showing high-intensity components, and T2-weighted MRI showing low-intensity components. The ball-like components in all images were not well enhanced. Laparotomic cyst resection was performed, and the surgical material revealed keratin balls inside the pancreatic LEC. Keratin components of a pancreatic LEC can take a liquid, sludge, or solid form. Clinicians must be aware of the variations in imaging to facilitate the differentiation and management of pancreatic cystic lesions.

Abbreviations: CA 19-9: carbohydrate antigen 19-9; CEA: carcinoembryonic antigen; DWI: diffusion-weighted image; LEC: lymphoepithelial cyst; IPMN: intraductal papillary neoplasm; MCN: mucinous cystic neoplasm.