Incidences of Pancreatic Malignancy and Mortality in Patients With Untreated Branch-Duct Intraductal Papillary Mucinous Neoplasms Undergoing Surveillance A Systematic Review

Objective: The aim of this study was to pool incidences of increased cyst size, malignant branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs), pancreatic malignancy, and pancreatic malignancy-related death during follow-up (FU) of BD-IPMN patients. Methods: Searches were performed from January 2010 to April 2016. All hits were checked on inclusion criteria, and outcomes were extracted. Incidences were pooled. Three subgroups were defined: (1) including only BD-IPMN patients, (2) short-interval FU (maximum 6 months), and (3) long-interval FU (> 6 months). Results: Thirty-one articles were enrolled, including 8455 patients (mean age, 66.4 years). Twenty-two studies included subgroup 1; 10 and 6 studies included, respectively, subgroups 2 and 3. Incidence of increased cyst size was 17.4%. In subgroups 1, 2, and 3, incidences were, respectively, 20.0%, 17.2%, and 31.7%. Incidence of malignant BD-IPMN was 2.5. In subgroups 1, 2, and 3, incidences were, respectively, 3.0%, 2.4%, and 3.3%. Incidence of pancreatic malignancy was 2.6%. In subgroups 1, 2, and 3, incidences were, respectively, 2.3%, 1.2%, and 4.0%. Incidence of death was 0.5%. In subgroups 1, 2, and 3, incidences were, respectively, 0.4%, 0.04%, and 0.12%. Conclusions: Although not significant, all incidences on long-interval FU were higher; therefore, short-interval FU seems necessary to find resectable lesions