Low Rates of Malignancy and Mortality in Asymptomatic Patients With Suspected Neoplastic Pancreatic Cysts Beyond 5 Years of Surveillance

Abstract

This article has an accompanying continuing medical education activity, also eligible for MOC credit, on page e67. Learning Objective-Upon completion of this activity, successful learners should be able to understand the prevalence of pancreatic cysts in clinical practice and determine the prognosis of asymptomatic pancreatic cysts. BACKGROUND & AIMS: The 2015 American Gastroenterological Association guidelines recommend discontinuation of surveillance of pancreatic cysts after 5 years, although there are limited data to support this recommendation. We aimed to determine the rate of pancreatic cancer development from neoplastic pancreatic cysts after 5 years of surveillance. METHODS: We performed a retrospective multicenter study, collecting data from 310 patients with asymptomatic suspected neoplastic pancreatic cysts, identified by endoscopic ultrasound from January 2002 to June 2010 at 4 medical centers in California. All patients were followed up for 5 years or more (median, 87 mo; range, 60-189 mo). Data were used to calculate the risk for pancreatic cancer and all-cause mortality. RESULTS: Three patients (1%) developed invasive pancreatic adenocarcinoma. Based on American Gastroenterological Association high-risk features (cyst size > 3 cm, dilated pancreatic duct, mural nodule), risks for cancer were 0%, 1%, and 15% for patients with 0, 1, or 2 high-risk features, respectively. Mortality from nonpancreatic causes was 8-fold higher than mortality from pancreatic cancer after more than 5 years of surveillance. CONCLUSIONS: There is a very low risk of malignant transformation of asymptomatic neoplastic pancreatic cysts after 5 years. Patients with pancreatic lesions and 0 or 1 high-risk feature have a less than 1% risk of developing pancreatic cancer, therefore discontinuation of surveillance can be considered for select patients. Patients with neoplastic pancreatic cysts with 2 high-risk features have a 15% risk of subsequent pancreatic cancer, therefore surgery or continued surveillance should be considered.

Development of a stratification tool to identify pancreatic intraductal papillary mucinous neoplasms at lowest risk of progression

“…In 2015, a meta‐analysis was published including 2177 patients under surveillance for SB‐IPMN, of which only 82 (3.7%) developed a pancreatic malignancy . Since then, several additional studies, each including at least 300 patients with at least 5 years of follow‐up, reported a pancreatic cancer risk of only 0%‐1.6% for small asymptomatic cysts . However, all these studies were retrospective and the actual, long‐term risk is yet to be determined by large and prospective studies.…”

Progression of pancreatic cystic lesions without any risk features is associated with initial cyst size and obesity

“…PCLs are detected in 1.9–2.1% of the patients on computed tomography (CT) and in 13.5–49.1% of the patients on magnetic resonance imaging, with the incidence increasing with age . Although various investigations into the progression rate and malignancy risk of PCLs have been previously reported, most studies only focused on definite or presumed branch duct intraductal papillary mucinous neoplasms (IPMNs). In clinical practice, the lesions we encounter are generally asymptomatic small PCLs, as opposed to definite neoplastic cystic lesions, such as IPMNs or mucinous cystic neoplasms.…”

Editorial: when, who and how—the ever‐evolving management of pancreatic cystic lesions. Authors’ reply

“…These limitations, however, are unavoidable at present, due to the lack of a well‐characterised cohort of individuals with low‐risk IPMNs that is large enough, has sufficient follow‐up time, and has been followed according to a pre‐defined protocol. A negative prediction tool focuses on pancreatic cystic lesions at lowest risk of malignant progression, recently estimated to be 0%‐1.6% . Inherently, the number of patients who develop malignancy in this target group is extremely low.…”