title: Management of branch-duct intraductal papillary mucinous neoplasms: a large single-center study to assess predictors of malignancy and long-term outcomes.
abstract: OBJECTIVE
  Management of branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) remains challenging. We determined factors associated with malignancy in BD-IPMNs and long-term outcomes.
  
  
  METHODS
  This retrospective cohort study included all patients with established BD-IPMNs by the International Consensus Guidelines (ICG) 2012 and/or pathologically confirmed BD-IPMNs in a tertiary care referral center between 2001 and 2013. Main outcome measures were the association between high-risk stigmata (HRS)/worrisome features (WFs) of the ICG 2012 and malignant BD-IPMNs, performance characteristics of EUS-FNA for the diagnosis of malignant BD-IPMNs, and recurrence and long-term outcomes of BD-IPMN patients undergoing surgery or imaging surveillance.
  
  
  RESULTS
  Of 364 BD-IPMN patients, 229 underwent imaging surveillance and 135 underwent surgery. Among the 135 resected BD-IPMNs, HRS/WFs on CT/magnetic resonance imaging (MRI) were similar between the benign and malignant groups, but main pancreatic duct (MPD) dilation (5-9 mm) was more frequently identified in malignant lesions. On EUS-FNA, mural nodules, MPD features suspicious for involvement, and suspicious/positive malignant cytology were more frequently detected in the malignant group with a sensitivity, specificity, and accuracy of 33%, 94%, and 86%; 42%, 91%, and 83%; and 33% 91%, and 82%, respectively. Mural nodules identified by EUS were missed by CT/MRI in 28% in the malignant group. Patients with malignant lesions had a higher risk of any IPMN recurrence during a mean follow-up period of 131 months (P = .01).
  
  
  CONCLUSIONS
  Among HRS and WFs of the ICG 2012, an MPD size of 5 to 9 mm on CT/MRI was associated with malignant BD-IPMNs. EUS features including mural nodules, MPD features suspicious for involvement, and suspicious/malignant cytology were accurate and highly specific for malignant BD-IPMNs. Our study highlights the incremental value of EUS-FNA over imaging in identifying malignant BD-IPMNs, particularly in patients without WFs and those with smaller cysts. Benign IPMN recurrence was observed in some patients up to 8 years after resection.
authors.affiliation: Indiana University School of Medicine, Indianapolis, Indiana, USA; Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand.
authors.forename: Wiriyaporn
authors.initials: W
authors.lastname: Ridtitid
authors.affiliation: Indiana University School of Medicine, Indianapolis, Indiana, USA.
authors.forename: John M
authors.initials: JM
authors.lastname: DeWitt
authors.affiliation: Indiana University School of Medicine, Indianapolis, Indiana, USA.
authors.forename: C Max
authors.initials: CM
authors.lastname: Schmidt
authors.affiliation: Indiana University School of Medicine, Indianapolis, Indiana, USA.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Roch
authors.affiliation: Indiana University School of Medicine, Indianapolis, Indiana, USA.
authors.forename: Jennifer Schaffter
authors.initials: JS
authors.lastname: Stuart
authors.affiliation: Indiana University School of Medicine, Indianapolis, Indiana, USA.
authors.forename: Stuart
authors.initials: S
authors.lastname: Sherman
authors.affiliation: Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates.
authors.forename: Mohammad A
authors.initials: MA
authors.lastname: Al-Haddad
mesh_terms: D000368:Aged; D021441:Carcinoma, Pancreatic Ductal / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D015331:Cohort Studies; D016208:Databases, Factual; D061765:Endoscopic Ultrasound-Guided Fine Needle Aspiration; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018297:Neoplasms, Cystic, Mucinous, and Serous / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D010183:Pancreatic Ducts / Q000000981:diagnostic imaging* / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D011379:Prognosis; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D047368:Tumor Burden