title: A novel approach to the diagnosis of pancreatic serous cystadenoma: needle-based confocal laser endomicroscopy.
abstract: OBJECTIVE
  The differential diagnosis of solitary pancreatic cystic lesions is frequently difficult. Needle-based confocal laser endomicroscopy (nCLE) performed during endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a new technology enabling real-time imaging of the internal structure of such cysts. The aim of this pilot study was to identify and validate new diagnostic criteria on nCLE for pancreatic cystic lesions.
  
  
  METHODS
  A total of 31 patients with a solitary pancreatic cystic lesion of unknown diagnosis were prospectively included at three centers. EUS-FNA was combined with nCLE. The final diagnosis was based on either a stringent gold standard (surgical specimen and/or positive cytopathology) or a committee consensus. Six nonblinded investigators reviewed nCLE sequences from patients with the most stringent final diagnosis, and identified a single feature that was only present in serous cystadenoma (SCA). The findings were correlated with the pathology of archived specimens. After a training session, four blinded independent observers reviewed a separate independent video set, and the yield and interobserver agreement for the criterion were assessed.
  
  
  RESULTS
  A superficial vascular network pattern visualized on nCLE was identified as the criterion. It corresponded on pathological specimen to a dense and subepithelial capillary vascularization only seen in SCA. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of this sign for the diagnosis of SCA were 87 %, 69 %, 100 %, 100 %, and 82 %, respectively. Interobserver agreement was substantial (κ = 0.77).
  
  
  CONCLUSIONS
  This new nCLE criterion seems highly specific for the diagnosis of SCA. The visualization of this criterion could have a direct impact on the management of patients by avoiding unnecessary surgery or follow-up.Clinicaltrials.gov NCT01563133.
authors.affiliation: Department of Gastroenterology, Hôpital privé Jean Mermoz, Générale de Santé, Lyon, France.
authors.forename: Bertrand
authors.initials: B
authors.lastname: Napoléon
authors.affiliation: Department of Biopathology, Centre Léon Bérard, Lyon, France.
authors.forename: Anne-Isabelle
authors.initials: AI
authors.lastname: Lemaistre
authors.affiliation: Department of Gastroenterology, Hôpital privé Jean Mermoz, Générale de Santé, Lyon, France.
authors.forename: Bertrand
authors.initials: B
authors.lastname: Pujol
authors.affiliation: Department of Hepatogastroenterology, Institut Paoli Calmettes, Marseille, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Caillol
authors.affiliation: Medicosurgical Department of Hepatogastroenterology, Saint-Philibert Hospital Centre, Lomme-lès-Lille, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Lucidarme
authors.affiliation: Department of Digestive Surgery, Hôpital privé Jean Mermoz, Générale de Santé, Lyon, France.
authors.forename: Raphaël
authors.initials: R
authors.lastname: Bourdariat
authors.affiliation: Department of Biopathology, Centre Léon Bérard, Lyon, France.
authors.forename: Blandine
authors.initials: B
authors.lastname: Morellon-Mialhe
authors.affiliation: Department of Gastroenterology, Hôpital privé Jean Mermoz, Générale de Santé, Lyon, France.
authors.forename: Fabien
authors.initials: F
authors.lastname: Fumex
authors.affiliation: Department of Gastroenterology, Hôpital privé Jean Mermoz, Générale de Santé, Lyon, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Lefort
authors.affiliation: Department of Gastroenterology, Hôpital privé Jean Mermoz, Générale de Santé, Lyon, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Lepilliez
authors.affiliation: Department of Gastroenterology, Clinique du Trocadéro, Paris, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Palazzo
authors.affiliation: Department of Biopathology, Institut Paoli Calmettes, Marseille, France.
authors.forename: Geneviève
authors.initials: G
authors.lastname: Monges
authors.affiliation: Medicosurgical Department of Hepatogastroenterology, Saint-Philibert Hospital Centre, Lomme-lès-Lille, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Filoche
authors.affiliation: Department of Hepatogastroenterology, Institut Paoli Calmettes, Marseille, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Giovannini
mesh_terms: D000328:Adult; D000368:Aged; D018293:Cystadenoma, Serous / Q000000981:diagnostic imaging / Q000473:pathology*; D003937:Diagnosis, Differential; D061765:Endoscopic Ultrasound-Guided Fine Needle Aspiration / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D010181:Pancreatic Cyst / Q000000981:diagnostic imaging / Q000473:pathology*; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D010865:Pilot Projects; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016037:Single-Blind Method