title: Pathologic Subtypes of Ampullary Adenocarcinoma: Value of Ampullary MDCT for Noninvasive Preoperative Differentiation.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the utility of ampullary MDCT in the noninvasive, preoperative differentiation of pancreatobiliary and intestinal subtypes of ampullary adenocarcinoma.
  
  
  METHODS
  This retrospective study included 32 patients (20 men, 12 women; age range, 41-81 years) with resected ampullary adenocarcinoma who underwent preoperative contrast-enhanced ampullary MDCT. Two radiologists, blinded to pathologic diagnosis of adenocarcinoma subtype, evaluated the presence of seven MDCT features independently. MDCT findings and ampullary adenocarcinoma subtypes were correlated using chi-square and Fisher exact tests. Interobserver agreement was evaluated using the Cohen kappa statistic.
  
  
  RESULTS
  When evaluated with ampullary MDCT, the intestinal and pancreatobiliary subtypes were significantly different in terms of lesion morphology (p < 0.0001), papillary shape (p < 0.0001), common bile duct (CBD) infiltration and dilatation (p = 0.003 and p = 0.0004, respectively), duodenopancreatic groove infiltration (p = 0.0009), and pancreaticoduodenal artery involvement (p = 0.004). Pancreatobiliary subtype tumors were more often infiltrative in morphology (18/18) and showed retracted papilla (14/18), CBD (18/18) and main pancreatic duct (MPD) infiltration (12/18), dilated CBD (18/18) and MPD (13/18), fixed duodenopancreatic groove appearance (15/18), and pancreaticoduodenal artery involvement (12/18). Intestinal subtype carcinomas were more frequently nodular (14/14) and had a bulging papilla (13/14), a free duodenopancreatic groove appearance (11/14), and no pancreaticoduodenal artery involvement (2/14). When all features were taken into account, MDCT showed sensitivity of 85.7% and specificity of 83.3% in differentiating intestinal and pancreatobiliary subtype tumors. Accuracy, positive predictive value, and negative predictive value of MDCT were 84.4%, 80%, and 88.2%, respectively. Interobserver agreement was almost perfect for the presence of each imaging feature (κ > 0.8).
  
  
  CONCLUSIONS
  Ampullary MDCT can be useful to differentiate pancreatobiliary and intestinal subtypes of ampullary adenocarcinoma preoperatively, provided the duodenum is optimally distended at imaging.
authors.affiliation: 1 Department of Diagnostic Imaging, Center of Radiology and MRI, Clinical Center of Serbia, University of Belgrade, School of Medicine, Pasterova 2, Belgrade 11000, Serbia.
authors.forename: Aleksandar M
authors.initials: AM
authors.lastname: Ivanovic
authors.affiliation: 2 Department of Radiology, Divisions of Abdominal Imaging and Body MRI, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA.|3 Present address: University of Pavia, Pavia, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Alessandrino
authors.affiliation: 1 Department of Diagnostic Imaging, Center of Radiology and MRI, Clinical Center of Serbia, University of Belgrade, School of Medicine, Pasterova 2, Belgrade 11000, Serbia.
authors.forename: Ruzica
authors.initials: R
authors.lastname: Maksimovic
authors.affiliation: 4 Department of Pathology, First Surgical Clinic, Clinical Center of Serbia, University of Belgrade, School of Medicine, Belgrade, Serbia.
authors.forename: Marjan
authors.initials: M
authors.lastname: Micev
authors.affiliation: 5 Department of Hepatobiliary and Pancreatic Surgery, First Surgical Clinic, Clinical Center of Serbia, University of Belgrade, School of Medicine, Belgrade, Serbia.
authors.forename: Slavenko
authors.initials: S
authors.lastname: Ostojic
authors.affiliation: 6 Department of Gastrointestinal Radiology, NorthShore University Health System, Evanston, IL.|7 Pritzker School of Medicine, University of Chicago, Chicago, IL.
authors.forename: Richard M
authors.initials: RM
authors.lastname: Gore
authors.affiliation: 2 Department of Radiology, Divisions of Abdominal Imaging and Body MRI, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA.
authors.forename: Koenraad J
authors.initials: KJ
authors.lastname: Mortele
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014670:Ampulla of Vater / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D003138:Common Bile Duct Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000379:methods*; D009367:Neoplasm Staging; D015588:Observer Variation; D011300:Preoperative Care; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: MDCT; ampullary adenocarcinoma; pancreatobiliary carcinoma