title: The No Endosonographic Detection of Tumor (NEST) Study: a case series of pancreatic cancers missed on endoscopic ultrasonography.
abstract: OBJECTIVE
  The purpose of this study was to identify possible associated factors that may have contributed to failure to detect a pancreatic neoplasm during endoscopic ultrasound (EUS) examinations by experienced endosonographers.
  
  
  METHODS
  A multicenter retrospective study was organized, and 20 cases of pancreatic neoplasms missed by nine experienced endosonographers were identified. Careful analysis of each case was carried out to identify the factors that might have led to the missed diagnosis on EUS.
  
  
  RESULTS
  Twelve patients with a missed pancreatic neoplasm had EUS features of chronic pancreatitis. Other factors that might have increased the likelihood of a false-negative EUS examination included a diffusely infiltrating carcinoma (n = 3), a prominent ventral/dorsal split (n = 2), and a recent episode (within the previous 4 weeks) of acute pancreatitis (n = 1). Five patients with a negative initial EUS underwent a follow-up EUS after 2-3 months, with a pancreatic mass being found in all cases. Three patients had a diffusely infiltrating pancreatic adenocarcinoma.
  
  
  CONCLUSIONS
  EUS is not a foolproof method of detecting a pancreatic neoplasm. Possible associated factors that may increase the likelihood of a false-negative EUS examination include chronic pancreatitis, a diffusely infiltrating carcinoma, a prominent ventral/dorsal split and a recent episode (< 4 weeks) of acute pancreatitis. If there is a high clinical suspicion of pancreatic neoplasm, if EUS and other imaging methods are negative, and if the patient does not undergo surgery, this study suggests that a repeat EUS after 2-3 months may be useful for detecting an occult pancreatic neoplasm.
authors.affiliation: Center for Endoscopic Ultrasound, University of Texas Medical Branch, Galveston, Texas 77555-0764, USA. msbhutan@utmb.edu
authors.forename: M S
authors.initials: MS
authors.lastname: Bhutani
authors.forename: F G
authors.initials: FG
authors.lastname: Gress
authors.forename: M
authors.initials: M
authors.lastname: Giovannini
authors.forename: R A
authors.initials: RA
authors.lastname: Erickson
authors.forename: M F
authors.initials: MF
authors.lastname: Catalano
authors.forename: A
authors.initials: A
authors.lastname: Chak
authors.forename: P H
authors.initials: PH
authors.lastname: Deprez
authors.forename: D O
authors.initials: DO
authors.lastname: Faigel
authors.forename: C C
authors.initials: CC
authors.lastname: Nguyen
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D002908:Chronic Disease; D003951:Diagnostic Errors; D019160:Endosonography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010179:Pancreas / Q000000981:diagnostic imaging* / Q000473:pathology*; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D010195:Pancreatitis / Q000000981:diagnostic imaging; D012189:Retrospective Studies