This review highlights new developments in the field of endoscopic ultrasound (EUS)-guided diagnosis and therapy of pancreatic cystic neoplasms. Studies pertinent to pancreatic cyst diagnosis by morphology, namely diagnostic accuracies of various criteria such as pancreatic cyst size, pancreatic duct size, mural nodules and use of EUS contrast agent are discussed. Tissue acquisition during EUS using a novel brush for cytology as well as microforceps is explored further. The role of multiple emerging molecular markers such as CEA, BRAF, KRAS, and GNAS, to name a few, is covered in detail. Recent developments relating to the utility of micro-RNAs in the analysis of cyst fluid is explored. Needle based confocal laser endomicroscopy for pancreatic cyst imaging is a recent development, and findings from recent trials are discussed. Furthermore, recent data regarding the role of ablative therapies using alcohol, paclitaxel and radiofrequency ablation of cyst is covered. Also, given the multiplicity of guidelines regarding management of pancreatic cystic neoplasms, we discuss the merits and shortcoming of these guidelines.
Biomarkers ; Catheter Ablation ; Cyst Fluid ; Diagnosis* ; Endoscopic Ultrasound-Guided Fine Needle Aspiration ; Needles ; Paclitaxel ; Pancreatic Cyst* ; Pancreatic Ducts ; Pancreatic Neoplasms ; Ultrasonography

Pancreatic cystic and neoplasms are being diagnosed with increasing frequency. Accurate diagnosis and determination of benign versus malignant lesions is crucial for determining need for surveillance versus surgery or endoscopic therapy as well as avoiding unnecessary surgery in cysts with no malignant potential. Tumor markers such as KRAS and GNAS hold promise, but which molecular marker or a combination of markers is most useful and cost effective remains to be seen. Advanced imaging with confocal laser endomicroscopy can serve as an optical biopsy and play a part in the diagnostic algorithm. Microforceps aided biopsy of pancreatic cyst wall and tumor contents hold great promise as they allow direct tissue acquisition. Much progress has been made in the role of EUS guided evaluation of pancreatic cystic neoplasms over the last several years, and with the advances enumerated above, the future is more than just a few shades of gray. Future studies should include prospective multi-arm trials of microforceps biopsy versus conventional EUS-FNA and use of biochemical and molecular markers, confocal laser endomicroscopy or a combination thereof to determine best approach to pancreatic cystic neoplasms. In Osler's words, ‘Medicine is a science of uncertainty and an art of probability’. Incorporation of advanced imaging and molecular markers into a new diagnostic algorithm with subsequent validation through retrospective and prospective studies has the potential to increase diagnostic accuracy and guide optimal management of patients and improve outcomes.