Tissue acquisition in pancreatic cystic lesions

Despite the progress achieved by scientific research in recent years, pancreatic cystic lesions (PCLs) remain a challenging clinical problem. A significant percentage of benign PCLs are still wrongly sent to surgery, with all the related risks of a high number of surgery-related complications and mortality. Diagnosis of the type of PCL, and risk stratification for malignancy are essential for a correct management of these lesions. Several guidelines have identified some clinical and morphological aspects suggesting the need for more accurate exams. Endoscopic ultrasound fine needle aspiration (EUS-FNA) of cystic fluid for cytology is the advised method of tissue acquisition in several guidelines, and the most used technique around the world. However sensitivity and adequacy of this technique are limited by the low amount of cells dispersed in cystic fluid. Alternative techniques have been tested to target the cystic walls in an attempt to obtain microhistologic specimens in order to augment the probability of obtaining an adequate diagnostic sample. The aim of this review is to offer a critical overview of the existing literature on tissue acquisition in PCLs, and emphasize advantages and disadvantages of each technique, and unclear areas that need to be investigated with future research.