In vivo characterization of pancreatic cystic lesions by needle-based confocal laser endomicroscopy (nCLE): proposition of a comprehensive nCLE classification confirmed by an external retrospective evaluation

Background and aims The differential diagnosis of solitary pancreatic cystic lesions is sometimes difficult. Needle-based confocal laser endomicroscopy(nCLE) performed during endoscopic ultrasound– fine-needle aspiration(EUS-FNA) enables real-time imaging of the internal structure of such cysts. Criteria have already been described for serous cystadenomaand intraductal papillary mucinous neoplasm(IPMN). The aims of the study were to determine new nCLE criteria for the diagnosis of pancreatic cystic lesions, to propose a comprehensive nCLE classification for the characterization of those lesions, and to carry out a first external retrospective validation .