Pancreatic cystic lesions (PCLs) are increasingly detected owing to the widespread use of high-resolution cross-sectional imaging [1,2]. These lesions encompass a broad biological spectrum, ranging from benign entities that require no treatment to neoplasms with malignant potential. Accurate classification and risk stratification are therefore essential to guide management, which ranges from simple follow-up to pancreatic surgery [1,3,4]. The ability to correctly evaluate these lesions has increased, but it is still suboptimal and sometimes leads to unnecessary surgical interventions, rising major concerns considering the morbidity and mortality risks related to pancreatic surgery [5].

Endoscopic ultrasound (EUS) has evolved from an adjunct to computed tomography (CT) and magnetic resonance imaging with cholangiopancreatography (MRI/MRCP) into a pivotal modality in this pathway. By providing superior spatial resolution and real-time assessment, EUS allows detailed evaluation of cyst morphology and communication with the main pancreatic duct (Wirsung's duct), mural nodules, septations, and solid lesions, and it enables tissue acquisition and fluid analysis when indicated [[6], [7], [8]]. Recent advances, including contrast-enhanced harmonic EUS, and high-sensitivity Doppler techniques, further improve the differentiation of different types of PCLs and the detection and characterization of mural nodules, and aid in estimating malignant potential [[9], [10], [11]]. Consequently, EUS imaging evaluation can guide the indication for further invasive diagnostic approaches, including EUS-guided fine-needle aspiration for cyst fluid analysis, EUS-guided fine-needle aspiration/biopsy of mural nodules, EUS-guided through-the-needle biopsy [12,13]. These approaches, as well as PCLs management and follow-up, are discussed in detail in other reviews of this Special Issue. This review summarizes the role of EUS imaging in the differential diagnosis and risk assessment of PCLs, with a focus on mucinous neoplasms (intraductal papillary mucinous neoplasm and mucinous cystic neoplasm), non-mucinous neoplastic cysts (serous cystic neoplasm, cystic pancreatic neuroendocrine tumor, and solid pseudopapillary neoplasm), and non-neoplastic cysts.