American Gastroenterological Association Technical Review on the Diagnosis and Management of Asymptomatic Neoplastic Pancreatic Cysts

Abstract

Pancreatic cysts are being identified with increasing frequency as a result of the escalating use of crosssectional imaging, typically for unrelated reasons. The incidenceof pancreatic cysts in theUSpopulation is estimated tobe between 3% and 15%, with increasing prevalence with age. Identification of a cystic lesion in the pancreas creates anxiety for both patients and clinicians related to the potential specter of a deadly malignancy. Historically, non-neoplastic inflammatory pancreatic pseudocysts were believed to be the most common pancreatic cysts; however, as imaging has become more sensitive, smaller, neoplastic cysts are more frequently detected. Thefindingof apancreatic abnormalitywithpotential association with malignancy is an increasing source of referral to specialists and an important driver of resource utilization, particularly in the United States. Imaging studies varywidely in their quality and interpretation, fueling the need for additional investigation. This technical review discusses the challenges in evaluating pancreatic cysts and critically examines the existing data set for evidence-based medical decision making. Although the concern for current or future malignancy is justified, a rational, evidence-based, cost-effective approach to care of the patient with a pancreatic cyst remains poorly defined. Despite the high prevalence of these lesions, investigators have recently questioned just how frequently a clinically relevant adverse outcome occurs, that is, the development of a life-threatening malignancy. This is a critical consideration given the cost of repeat imaging, performance of invasiveprocedures such as endoscopic ultrasonography (EUS) with or without fine-needle aspiration (FNA), and consideration of a major pancreatic resection with the substantial attendant morbidity and mortality, particularly in the aging population with a high rate of prevalent cysts. In a recent analysis, investigators using the Surveillance, Epidemiology, and End Results (SEER) database estimated an annual prevalence of 1137 mucin-producing pancreatic adenocarcinomas with a concurrent prevalence of nearly 3.5 million cysts in the samepopulation, concluding thatmalignant transformation is a very rare event. In this clinical context, the American Gastroenterological Association has commissioned an evidence-based review of the diagnosis and management of pancreatic cysts.