title: Intravoxel incoherent motion diffusion-weighted MR imaging of breast cancer: association with histopathological features and subtypes.
abstract: OBJECTIVE
  To evaluate the associations between intravoxel incoherent motion (IVIM)-derived parameters and histopathological features and subtypes of breast cancer.
  
  
  METHODS
  Pre-operative MRI from 275 patients with unilateral breast cancer was analyzed. The apparent diffusion coefficient (ADC) and IVIM parameters [tissue diffusion coefficient (Dt), perfusion fraction (fp) and pseudodiffusion coefficient] were obtained from cancer and normal tissue using diffusion-weighted imaging with b-values of 0, 30, 70, 100, 150, 200, 300, 400, 500 and 800 s mm(-2). We then compared the IVIM parameters of tumours with different histopathological features and subtypes.
  
  
  RESULTS
  The ADC and Dt were lower and fp was higher in cancers than in normal tissues (p < 0.001). The Dt was lower in high Ki-67 cancer than in low Ki-67 cancer (p = 0.019), whereas ADC showed no significant difference (p = 0.309). Luminal B [human epidermal growth factor receptor 2 (HER2)-negative] cancer showed lower ADC (p = 0.003) and Dt (p = 0.001) than other types.
  
  
  CONCLUSIONS
  We found low tissue diffusivity in high Ki-67 cancer and luminal B (HER2-negative) cancer using IVIM imaging.
  
  
  CONCLUSIONS
  Low tissue diffusivity is more clearly shown in high Ki-67 tumours and luminal B (HER2-negative) tumours with the IVIM model.
authors.affiliation: 1 Department of Radiology, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Yunju
authors.initials: Y
authors.lastname: Kim
authors.affiliation: 1 Department of Radiology, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Kyounglan
authors.initials: K
authors.lastname: Ko
authors.affiliation: 1 Department of Radiology, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Daehong
authors.initials: D
authors.lastname: Kim
authors.affiliation: 2 Molecular Imaging and Therapy Branch, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Changki
authors.initials: C
authors.lastname: Min
authors.affiliation: 3 Department of Radiology, New York University School of Medicine, New York, NY, USA.
authors.forename: Sungheon G
authors.initials: SG
authors.lastname: Kim
authors.affiliation: 4 Biometric Research Branch, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Jungnam
authors.initials: J
authors.lastname: Joo
authors.affiliation: 4 Biometric Research Branch, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Boram
authors.initials: B
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001940:Breast / Q000000981:diagnostic imaging / Q000473:pathology; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008875:Middle Aged; D009038:Motion; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity