title: Imaging features of invasive lobular carcinoma: comparison with invasive ductal carcinoma.
abstract: OBJECTIVE
  The aim of this study was to evaluate the imaging findings of invasive lobular carcinoma (ILC) compared to those of invasive ductal carcinoma (IDC).
  
  
  METHODS
  The study included ILCs (n = 27) and IDCs (n = 85). Imaging findings were retrospectively evaluated, according to the BI-RADS lexicon. We compared the imaging findings, multiplicity, and magnetic resonance imaging (MRI) detection accuracy of ILC with those of IDC.
  
  
  RESULTS
  At mammography, normal findings and mass lesions were more frequent with ILCs (14.8% and 59.2%, respectively) than with IDCs (1.2% and 44.7%, respectively) (P = 0.009). With ultrasonography (US), posterior acoustic shadowing was more frequently seen in ILCs (59.2%) than in IDCs (15.8%) (P < 0.001). With MRI, both ILCs and IDCs most commonly appeared as a heterogeneously enhancing, irregular mass with a spiculated border. Multifocality was more frequently associated with ILCs (40.7%) than with IDCs (14.1% 1% 0.002). However, multicentricity and bilaterality were not different between the two groups. The sensitivity and specificity of MRI for the detection of multiplicity were 91.6% and 73.3%, respectively, for ILCs and 83.3% and 80.3%, respectively, for IDCs.
  
  
  CONCLUSIONS
  Normal findings, mass lesions on mammography, and posterior acoustic shadowing on US were more frequently associated with ILCs than with IDCs. Multifocality was more prevalent with ILCs than with IDCs.
authors: Department of Radiology, St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Youido-dong, Yongdungpo-gu, Seoul 150-713, Korea.
authors: Sung Hun
authors: SH
authors: Kim
authors: Eun Suk
authors: ES
authors: Cha
authors: Chang Suk
authors: CS
authors: Park
authors: Bong Joo
authors: BJ
authors: Kang
authors: In Yong
authors: IY
authors: Whang
authors: A Won
authors: AW
authors: Lee
authors: Byung Joo
authors: BJ
authors: Song
authors: Jeongmi
authors: J
authors: Park
mesh_terms: D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis* / Q000473:pathology; D018275:Carcinoma, Lobular / Q000175:diagnosis* / Q000473:pathology; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008327:Mammography; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D016217:Ultrasonography, Mammary