title: Association between Parenchymal Enhancement of the Contralateral Breast in Dynamic Contrast-enhanced MR Imaging and Outcome of Patients with Unilateral Invasive Breast Cancer.
abstract: OBJECTIVE
  To retrospectively investigate whether parenchymal enhancement in dynamic contrast material-enhanced magnetic resonance (MR) imaging of the contralateral breast in patients with unilateral invasive breast cancer is associated with therapy outcome.
  
  
  METHODS
  After obtaining approval of the institutional review board and patients' written informed consent, 531 women with unilateral invasive breast cancer underwent dynamic contrast-enhanced MR imaging between 2000 and 2008. The contralateral parenchyma was segmented automatically, in which the mean of the top 10% late enhancement was calculated. Cox regression was used to test associations between parenchymal enhancement, patient and tumor characteristics, and overall survival and invasive disease-free survival. Subset analyses were performed and stratified according to immunohistochemical subtypes and type of adjuvant treatment received.
  
  
  RESULTS
  Median follow-up was 86 months. Age (P < .001) and immunohistochemical subtype (P = .042) retained significance in multivariate analysis for overall survival. In patients with estrogen receptor-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer (n = 398), age (P < .001), largest diameter on MR images (P = .049), and parenchymal enhancement (P = .011) were significant. In patients who underwent endocrine therapy (n = 174), parenchymal enhancement was the only significant covariate for overall survival and invasive disease-free survival (P < .001).
  
  
  CONCLUSIONS
  Results suggest that parenchymal enhancement in the contralateral breast of patients with invasive unilateral breast cancer is significantly associated with long-term outcome, particularly in patients with estrogen receptor-positive, human epidermal growth factor receptor 2-negative breast cancer. Lower value of the mean top 10% enhancement of the parenchyma shows potential as a predictive biomarker for relatively poor outcome in patients who undergo endocrine therapy. These results should, however, be validated in a larger study.
authors: From the Image Sciences Institute (B.H.M.v.d.V., I.D., K.G.A.G.) and Department of Radiology (B.H.M.v.d.V., I.D., R.M.P., K.G.A.G.), University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, PO Box 85500, 3508 GA Utrecht, the Netherlands; and Department of Radiology, the Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, the Netherlands (C.E.L.).
authors: Bas H M
authors: BH
authors: van der Velden
authors: From the Image Sciences Institute (B.H.M.v.d.V., I.D., K.G.A.G.) and Department of Radiology (B.H.M.v.d.V., I.D., R.M.P., K.G.A.G.), University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, PO Box 85500, 3508 GA Utrecht, the Netherlands; and Department of Radiology, the Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, the Netherlands (C.E.L.).
authors: Ivan
authors: I
authors: Dmitriev
authors: From the Image Sciences Institute (B.H.M.v.d.V., I.D., K.G.A.G.) and Department of Radiology (B.H.M.v.d.V., I.D., R.M.P., K.G.A.G.), University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, PO Box 85500, 3508 GA Utrecht, the Netherlands; and Department of Radiology, the Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, the Netherlands (C.E.L.).
authors: Claudette E
authors: CE
authors: Loo
authors: From the Image Sciences Institute (B.H.M.v.d.V., I.D., K.G.A.G.) and Department of Radiology (B.H.M.v.d.V., I.D., R.M.P., K.G.A.G.), University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, PO Box 85500, 3508 GA Utrecht, the Netherlands; and Department of Radiology, the Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, the Netherlands (C.E.L.).
authors: Ruud M
authors: RM
authors: Pijnappel
authors: From the Image Sciences Institute (B.H.M.v.d.V., I.D., K.G.A.G.) and Department of Radiology (B.H.M.v.d.V., I.D., R.M.P., K.G.A.G.), University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, PO Box 85500, 3508 GA Utrecht, the Netherlands; and Department of Radiology, the Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, the Netherlands (C.E.L.).
authors: Kenneth G A
authors: KG
authors: Gilhuijs
mesh_terms: D001943:Breast Neoplasms / Q000473:pathology* / Q000628:therapy; D002277:Carcinoma / Q000473:pathology* / Q000628:therapy; D003287:Contrast Media; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D011856:Radiographic Image Enhancement; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media