EUS-FNA in cystic pancreatic lesions: Where are we now and where are we headed in the future?

EUS-FNA is often performed in the evaluation of Cystic Pancreatic Lesions (CPL) for a better preoperative characterization. The objective is to identify premalignant lesions as Mucinous Cystic Neoplasms, and/or a malignant transformation of them (adenocarcinoma). The role of cytological evaluation in this setting is discouraging and intracystic markers analysis, mainly CEA, lacks of a good specificity for the detection of mucinous neoplasms. New devices and approaches have emerged to overcome these problems as the cytology brush (Echobrush), the small mini-biopsy foceps, the cystoscopy and the needle Confocal LASER Endomicroscopy (nCLE), showing in some studies good rates of accuracy for distinguishing among mucinosus and non-mucinous neoplasms. However, intracystic molecular marker analysis, by identifying mutations in DNA of particular genes as KRAS, GNAS, VHL, CDKN2A and others constitute the most relevant advancement of last years and will contribute in the next future to a better management of CPL. The role of EUS-FNA according to international guidelines is still controversial. While 2012 Fukuoka guidelines are restrictive in their indications AGA 2015 guidelines support it when high risk features are present, enhancing the role of the cytological evaluation in taking decisions.