Needle-based confocal laser endomicroscopy in pancreatic cystic tumors assessment

Pancreatic cystic tumors (PCT) are relatively common findings in general population due to the widespread use of cross-sectional imaging. PCT can be benign, with premalignant potential or malignant, a different management being applied for each type: benign cysts are usually referred for follow-up (based on imaging), while premalignant or malignant lesions should be surgically resected. The aim of this review is to describe the latest imaging technique that could be used for PCT diagnosis and to establish its clinical impact. Endoscopic ultrasound (EUS) is generally used to evaluate a pancreatic mass and to identify its characteristics. It offers a good visualization of the lesion. When combined with fine needle aspiration and cystic fluid analysis, the diagnosis potential is increased, although its accuracy for differentiating benign and malign tumors remains modest. EUS-guided needle-based confocal laser endomicroscopy (nCLE) is a new imaging technique that uses a miniprobe thin enough to be passed through a 19G needle. It provides in vivo images of the pancreas at a cellular level, offering the possibility to assess any changes that might have occurred. Several studies have shown that nCLE is feasible to use for PCT evaluation, imaging criteria being established with 100% specificity for intraductal papillary mucinous neoplasms (IPMN) and serous cystadenoma (SCA). Regarding the safety, more studies are needed. EUS-guided nCLE appears to be a new imaging technique that provides encouraging results for differential diagnosis between mucinous/non-mucinous cysts.