title: Dynamic contrast-enhanced magnetic resonance imaging and invasive breast cancer: primary lesion kinetics correlated with axillary lymph node extracapsular extension.
abstract: OBJECTIVE
  To determine if dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) peak enhancement (PE) of primary breast cancer can predict the presence of lymph node extracapsular extension (LNECE) in patients with axillary metastatic disease.
  
  
  METHODS
  In all, 167 patients treated with radiotherapy for invasive breast cancer from January 1, 2006 to November 1, 2007 were retrospectively identified. Patients with DCE-MRI and surgical axillary staging were included in this study. PE of primary tumors was compared according to axillary nodal status: negative, positive without LNECE, or positive with LNECE. A receiver operator characteristic curve (ROC) was plotted to determine accuracy of PE to predict LNECE.
  
  
  RESULTS
  Forty-six patients met the study criteria. Thirty-two (70%) were node-negative, 9 (19%) were node-positive without LNECE, and 5 (11%) were node-positive with LNECE. PE was greater for patients with LNECE (mean 365%) compared to node-positive patients without LNECE (mean 183%) P = 0.05 and node-negative patients (mean 144%) P = 0.0012. Area under the ROC curve was 0.93.
  
  
  CONCLUSIONS
  DCE-MRI PE may be a surrogate marker for LNECE. If validated, DCE-MRI may provide noninvasive kinetic information informing axillary nodal status for patients who receive chemotherapy prior to surgical axillary staging or forego axillary dissection after a positive sentinel node biopsy.
authors.affiliation: Department of Radiation Oncology, University of Washington Medical Center, Seattle, Washington, USA. Loiselle@uw.edu
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Loiselle
authors.forename: Peter R
authors.initials: PR
authors.lastname: Eby
authors.forename: Sue
authors.initials: S
authors.lastname: Peacock
authors.forename: Janice N
authors.initials: JN
authors.lastname: Kim
authors.forename: Constance D
authors.initials: CD
authors.lastname: Lehman
mesh_terms: D001365:Axilla; D001943:Breast Neoplasms / Q000473:pathology*; D003287:Contrast Media / Q000493:pharmacokinetics; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007700:Kinetics; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology* / Q000601:surgery*; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008657:Metabolic Clearance Rate; D009361:Neoplasm Invasiveness; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021701:Sentinel Lymph Node Biopsy
chemical_list: D003287:Contrast Media