PURPOSE: To identify characteristic magnetic resonance (MR) features of focal autoimmune pancreatitis (f-AIP) useful for differentiation from pancreatic cancer (PC). METHODS: We retrospectively analyzed MR imaging findings of 20 f-AIP lesions and 40 PC lesions smaller than 40 mm in diameter. On fat-suppressed T2-weighted images and dynamic contrast-enhanced fat-suppressed T1-weighted images (DCE-T1WI), we classified MR features of internal signal intensity for each lesion into homogeneous, speckled, or target type. We assessed the sensitivity, specificity, and accuracy of these findings in the diagnosis of f-AIP. We also investigated the incidence of previously reported findings for differentiation between f-AIP and PC. RESULTS: Speckled enhancement within a hypointense or isointense lesion on pancreatic phase DCE-T1WI (speckled type) was observed more frequently in f-AIP than in PC, with high sensitivity, high specificity, and high accuracy. Hypointensity to hyperintensity surrounding a less enhanced focal area on DCE-T1WIs (target type) and upper stream main pancreatic duct dilatation were observed more frequently in PC than in f-AIP. CONCLUSION: Speckled enhancement inside an f-AIP lesion on pancreatic phase DCE-T1WI was useful for differentiation from PC.
PURPOSE: To identify characteristic magnetic resonance (MR) features of focal autoimmune pancreatitis (f-AIP) useful for differentiation from pancreatic cancer (PC). METHODS: We retrospectively analyzed MR imaging findings of 20 f-AIP lesions and 40 PC lesions smaller than 40 mm in diameter. On fat-suppressed T2-weighted images and dynamic contrast-enhanced fat-suppressed T1-weighted images (DCE-T1WI), we classified MR features of internal signal intensity for each lesion into homogeneous, speckled, or target type. We assessed the sensitivity, specificity, and accuracy of these findings in the diagnosis of f-AIP. We also investigated the incidence of previously reported findings for differentiation between f-AIP and PC. RESULTS: Speckled enhancement within a hypointense or isointense lesion on pancreatic phase DCE-T1WI (speckled type) was observed more frequently in f-AIP than in PC, with high sensitivity, high specificity, and high accuracy. Hypointensity to hyperintensity surrounding a less enhanced focal area on DCE-T1WIs (target type) and upper stream main pancreatic duct dilatation were observed more frequently in PC than in f-AIP. CONCLUSION: Speckled enhancement inside an f-AIP lesion on pancreatic phase DCE-T1WI was useful for differentiation from PC.
Authors: H Hamano; S Kawa; A Horiuchi; H Unno; N Furuya; T Akamatsu; M Fukushima; T Nikaido; K Nakayama; N Usuda; K Kiyosawa Journal: N Engl J Med Date: 2001-03-08 Impact factor: 91.245
Authors: Dushyant V Sahani; Sanjeeva P Kalva; James Farrell; Michael M Maher; Sanjay Saini; Peter R Mueller; Gregory Y Lauwers; Carlos D Fernandez; Andrew L Warshaw; Joseph F Simeone Journal: Radiology Date: 2004-09-30 Impact factor: 11.105
Authors: T Gabata; O Matsui; M Kadoya; J Yoshikawa; S Miyayama; T Takashima; T Nagakawa; M Kayahara; A Nonomura Journal: Radiology Date: 1994-12 Impact factor: 11.105
Authors: Lawrence Mj Best; Vishal Rawji; Stephen P Pereira; Brian R Davidson; Kurinchi Selvan Gurusamy Journal: Cochrane Database Syst Rev Date: 2017-04-17