title: Correlations between apparent diffusion coefficient values and prognostic factors of breast cancer.
abstract: OBJECTIVE
  We investigated possible correlations between apparent diffusion coefficient (ADC) values and prognostic factors of breast cancer.
  
  
  METHODS
  We retrospectively evaluated 81 patients who underwent magnetic resonance (MR) imaging of the breast and were diagnosed pathologically with invasive ductal carcinoma (IDC) not otherwise specified with invasive foci one cm or larger. We excluded ductal carcinoma in situ and IDC with invasive foci smaller than one cm because small lesions decrease the reliability of signal intensity of diffusion-weighted imaging (DWI). We also excluded special type cancers. We used t-test to compare the mean ADC values of cancers of Stage pT1 (≤2 cm) versus pT2 or 3 (>2 cm), cancers with versus without vascular invasion, axillary lymph node (N)-positive versus N-negative cancers, estrogen receptor (ER)-positive versus ER-negative cancers, and progesterone receptor (PgR)-positive versus PgR-negative cancers. We analyzed correlations between the ADC value with nuclear grade (NG) and human epidermal growth factor receptor 2 (HER2) score by rank test using Spearman's correlation coefficient.
  
  
  RESULTS
  The mean ADC value was significantly higher for N-positive (n=28; 0.97 ± 0.20 × 10(-3) mm(2)/s) than N-negative cancers (n=53; 0.87 ± 0.17 × 10(-3) mm(2)/s) (P=0.017); significantly lower for ER-positive (n=63; 0.88 ± 0.15 × 10(-3) mm(2)/s) than ER-negative cancers (n=18; 1.01 ± 0.21 × 10(-3) mm(2)/s) (P=0.005); and significantly lower for PgR-positive (n=47; 0.88 ± 0.16 × 10(-3) mm(2)/s) than PgR-negative cancers (n=34; 0.95 ± 0.18 × 10(-3) mm(2)/s) (P=0.048). Tumor size, vascular invasion, NG, and HER2 status showed no significant correlation with ADC values.
  
  
  CONCLUSIONS
  ADC values were higher for N-positive and ER-negative breast cancers than N-negative and ER-positive cancers.
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kamitani
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Matsuo
authors.forename: Hidetake
authors.initials: H
authors.lastname: Yabuuchi
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Fujita
authors.forename: Michinobu
authors.initials: M
authors.lastname: Nagao
authors.forename: Mikako
authors.initials: M
authors.lastname: Jinnouchi
authors.forename: Masato
authors.initials: M
authors.lastname: Yonezawa
authors.forename: Yuzo
authors.initials: Y
authors.lastname: Yamasaki
authors.forename: Eriko
authors.initials: E
authors.lastname: Tokunaga
authors.forename: Makoto
authors.initials: M
authors.lastname: Kubo
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Takashi
authors.initials: T
authors.lastname: Yoshiura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Honda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000473:pathology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007564:Japan / Q000453:epidemiology; D008875:Middle Aged; D015995:Prevalence; D011379:Prognosis; D015203:Reproducibility of Results; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D013223:Statistics as Topic