ACG Clinical Guideline: Diagnosis and Management of Pancreatic Cysts

Abstract

Pancreatic cysts are very common with the majority incidentally identified. There are several types of pancreatic cysts; some types can contain cancer or have malignant potential, whereas others are benign. However, even the types of cysts with malignant potential rarely progress to cancer. At the present time, the only viable treatment for pancreatic cysts is surgical excision, which is associated with a high morbidity and occasional mortality. The small risk of malignant transformation, the high risks of surgical treatment, and the lack of high-quality prospective studies have led to contradictory recommendations for their immediate management and for their surveillance. This guideline will provide a practical approach to pancreatic cyst management and recommendations for cyst surveillance for the general gastroenterologist.

Management Algorithm for Cystic Pancreatic Lesions

“…EUS ± fine needle aspiration (FNA) is recommended in adjunction to cross-sectional imaging in cases of diagnostic uncertainty regarding the type of cystic lesion and for risk stratification [3,4]. Data on its diagnostic accuracy are conflicting as it is more operator-dependent [8].…”

“…It has a sensitivity and specificity of 63% (95% CI 59-67) and 93% (95% CI 90-95), respectively, for identifying IPMNs and MCNs in a meta-analysis of 18 papers [9,10]. The recommended cutoff for cyst CEA is >192-200 ng/ml which results in about 80% accuracy for the diagnosis of mucinous lesions [3,4,10]. Amylase or lipase levels are elevated in lesions communicating with the pancreatic ductal system (BD-IPMN, pseudocysts) and can be measured in addition to CEA; however, they are less specific.…”

“…Notably, in the rare case of MCN in a male patient, malignant transformation seems to occur more often. If cystic lesions change rapidly in size, some evidence points towards a higher risk of malignancy [3]. …”

“…In general, the risk of high-grade dysplasia or malignancy in IPMN varies greatly across the literature and seems to be uniformly higher in a series of surgical cases (BD-IPMN 6.1-47.9%, MD-IPMN 36-100%) compared to the annual progression rate in prospective or retrospective cohorts that underwent surveillance (BD-IPMN 1.4-6.9%) [3,4]. In the first place, this seems to be a strong indicator of a selection bias towards symptomatic or otherwise clinically and radiologically remarkable patients enriched in surgical cohorts.…”

“…In patients who are not suited for surgery and do not have symptoms, incidental cystic pancreatic lesions do not require follow-up as it will not influence the clinical course [3,4]. In all other cases, the major question is whether or not the lesion harbors risk factors for malignancy or whether it has a potential for malignant development in the future.…”