Pancreatic cystic lesions and the role of contrast enhanced endoscopic ultrasound.

An exponential rise in the use of cross-sectional imaging has led to an increase in the incidental identification of pancreatic cystic lesions (PCL); however, with many subtypes defined to date and heterogeneous morphology with often absent defining radiological features, PCLs present a diagnostic challenge. Computed tomography (CT) and/or magnetic resonance imaging (MRI) alone are frequently not sufficient to provide accurate characterisation. Endoscopic ultrasound (EUS) has an important role in the evaluation and classification of PCLs through its ability to define the internal architecture, which is further enhanced by the use of contrast medium. It is also used widely for the surveillance of larger cysts (>2 cm), which are associated with a greater malignant potential. The aim of this review is to demonstrate the role of contrast-enhanced (CE)-EUS in the diagnosis and risk stratification of PCLs. The features of the main non-neoplastic and neoplastic PCLs observed on CE-EUS are provided. When used in combination with other imaging techniques and patient characteristics, CE-EUS offers a more accurate assessment of PCLs and aids risk stratification. Additionally, CE-EUS enables assessment of parenchymal perfusion improving the precision of cyst characterisation and targeted biopsy of worrisome components. The International Consensus Guidelines recommend regular follow up for patients with mucinous or indeterminate PCLs that are fit enough for surgery. With the growing range of tools available to assess PCLs including CE-EUS, it is hoped that patients can be steered towards surgery, surveillance, or discharge with increasing accuracy.