title: Pancreatic multicenter ultrasound study (PAMUS).
abstract: OBJECTIVE
  To describe the typical CEUS pattern of pancreatic lesions and to evaluate the diagnostic accuracy of Contrast-enhanced ultrasound (CEUS) in their characterization.
  
  
  METHODS
  All US and CEUS examinations of focal pancreatic masses performed in six centers during a period of five years were reviewed. Inclusion criteria were: focal pancreatic mass pathologically proved, visible at ultrasound (US) and studied with CEUS. All lesions were then evaluated for size, aspect and enhancement pattern. Sensitivity, specificity, positive and negative predictive values with 95% CIs were calculated to define diagnostic accuracy of CEUS in respect to pathology. Diagnostic confidence of US and CEUS, discerning between benign and malignant lesions, were represented by using ROC (receiver operating characteristics) curves. Agreement was evaluated by means of k statistics.
  
  
  RESULTS
  1439 pancreatic lesions were included. At CEUS the lesions were divided into solid (89%) and cystic (12%) masses and classified into six and eight categories, respectively. Among the solid lesions, adenocarcinomas were characterized with an accuracy of 87.8%. Among the cystic lesions, cystic tumors were diagnosed with an accuracy of 97.1%. ROC curve area increased from 0.637 for US to 0.877 for CEUS (p<0.0001). Inter-observer agreement was slightly higher for solid (k=0.78) than cystic (k=0.62) lesions. In none of the centers side effects were reported.
  
  
  CONCLUSIONS
  CEUS is accurate in the characterization of pancreatic lesions. CEUS should be considered as a complementary imaging method for pancreatic lesions characterization.
authors.affiliation: Department of Radiology, University Hospital G.B. Rossi, University of Verona, Italy. mirko.donofrio@univr.it
authors.forename: Mirko
authors.initials: M
authors.lastname: D'Onofrio
authors.forename: Emilio
authors.initials: E
authors.lastname: Barbi
authors.forename: Christoph F
authors.initials: CF
authors.lastname: Dietrich
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kitano
authors.forename: Kazushi
authors.initials: K
authors.lastname: Numata
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sofuni
authors.forename: Francesco
authors.initials: F
authors.lastname: Principe
authors.forename: Anna
authors.initials: A
authors.lastname: Gallotti
authors.forename: Giulia A
authors.initials: GA
authors.lastname: Zamboni
authors.forename: Roberto Pozzi
authors.initials: RP
authors.lastname: Mucelli
mesh_terms: D005260:Female; D006801:Humans; D038622:Internationality; D008297:Male; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D015995:Prevalence; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000706:statistics & numerical data*