title: Risk of pancreatic malignancy and mortality in branch-duct IPMNs undergoing surveillance: A systematic review and meta-analysis.
abstract: BACKGROUND
  Safety of non-operative management for low-risk branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) is debated.
  
  
  OBJECTIVE
  To perform a systematic review/meta-analysis to determine their risk of developing pancreatic malignancy and of pancreatic malignancy-related deaths.
  
  
  METHODS
  A MEDLINE search was performed and methodology was based on PRISMA statement. Incidence rates of overall pancreatic malignancy, malignant BD-IPMN, IPMN-distinct PDAC, and of pancreatic malignancy-related death rates were calculated by dividing the total number of events by the total number of person-years (pyrs) of follow-up. Heterogeneity was determined by I(2) statistic.
  
  
  RESULTS
  20 studies including 2177 patients were included. Mean follow-up ranged from 29.3 to 76.7 months. Overall, 82 patients (3.7%) developed a pancreatic malignancy with a pooled estimate rate of 0.007/pyrs (I(2)=32.8%). The pooled estimate rate of malignant IPMN was 0.004/pyrs (I(2)=40.8%), and the pooled estimate rate of distinct PDAC 0.002/pyrs (I(2)=0%). The rate of death due to pancreatic malignancy during follow-up was 0.9%, with an overall pooled estimate rate of death of 0.002/pyrs (I(2)=0%).
  
  
  CONCLUSIONS
  Non-operative management of low-risk BD-IPMN is safe, with a very low risk of malignant transformation of IPMN and of distinct PDAC. The rate of pancreatic malignancy-related mortality is low, particularly when compared with the mortality of pancreatic surgery.
authors.affiliation: Division of Pancreatic Surgery, Vita-Salute University, San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Crippa
authors.affiliation: Digestive and Liver Disease Unit, S. Andrea Hospital, Faculty of Medicine and Psychology, Sapienza University of Rome, Italy.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Capurso
authors.affiliation: Gastroenterology Unit, Internal Medicine Department, University of Palermo, Palermo, Italy.
authors.forename: Calogero
authors.initials: C
authors.lastname: Cammà
authors.affiliation: Digestive and Liver Disease Unit, S. Andrea Hospital, Faculty of Medicine and Psychology, Sapienza University of Rome, Italy.
authors.forename: Gianfranco Delle
authors.initials: GD
authors.lastname: Fave
authors.affiliation: Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, USA.
authors.forename: Carlos Fernández-Del
authors.initials: CF
authors.lastname: Castillo
authors.affiliation: Division of Pancreatic Surgery, Vita-Salute University, San Raffaele Scientific Institute, Milan, Italy. Electronic address: falconi.massimo@hsr.it.
authors.forename: Massimo
authors.initials: M
authors.lastname: Falconi
mesh_terms: D021441:Carcinoma, Pancreatic Ductal / Q000453:epidemiology* / Q000401:mortality; D002471:Cell Transformation, Neoplastic; D006801:Humans; D018297:Neoplasms, Cystic, Mucinous, and Serous / Q000473:pathology*; D010183:Pancreatic Ducts; D010190:Pancreatic Neoplasms / Q000453:epidemiology* / Q000401:mortality / Q000473:pathology*; D012307:Risk Factors; D057832:Watchful Waiting
keywords: Follow-up; Non-operative management; Pancreatectomy; Pancreatic cancer