title: Comparison of MDCT and MRI for evaluating the intraductal component of breast cancer.
abstract: OBJECTIVE
  The purpose of our study was to compare the accuracy of MDCT and MRI for evaluating the intraductal component of breast cancer.
  
  
  METHODS
  Sixty-nine patients with histologically proven invasive carcinoma underwent MDCT and MRI. Retrospectively, two radiologists performed a blinded review of the MDCT and MRI. Cases with intraductal component enhancement were classified into two morphologic types: ductal extension and segmental distribution. The lengths of the main tumor and of the intraductal component were measured in cases with ductal extension. For cases with segmental distribution, only the maximum length of the tumor was measured.
  
  
  RESULTS
  The sensitivity, specificity, and accuracy in detecting the intraductal component were 61%, 88%, and 71%, respectively, using MDCT; and 75%, 88%, and 80%, respectively, using MRI. MRI revealed the presence of the intraductal component with significantly higher sensitivity than did MDCT (p = 0.031). In the analysis of the length of the intraductal component in cases with ductal extension, which had relatively small intraductal components, underestimation by 15 mm or more was significantly less frequent with MRI than with MDCT (p = 0.008). There was no significant difference between MDCT and MRI in the evaluation of the maximum length of tumors in cases with segmental distribution, which had relatively large intraductal components.
  
  
  CONCLUSIONS
  Compared with MDCT, MRI revealed the presence of the intraductal component with higher sensitivity and equivalent specificity. In cases with ductal extension, MRI is more precise than MDCT for determination of the margin for surgical removal, with less underestimation of the extent of the intraductal component.
authors.affiliation: Department of Diagnostic Radiology, Graduate School of Medicine, Tohoku University, Sendai, Miyagi, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Shimauchi
authors.forename: Takayuki
authors.initials: T
authors.lastname: Yamada
authors.forename: Akihiro
authors.initials: A
authors.lastname: Sato
authors.forename: Kei
authors.initials: K
authors.lastname: Takase
authors.forename: Shin
authors.initials: S
authors.lastname: Usami
authors.forename: Takanori
authors.initials: T
authors.lastname: Ishida
authors.forename: Takuya
authors.initials: T
authors.lastname: Moriya
authors.forename: Shoki
authors.initials: S
authors.lastname: Takahashi
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis*; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods