title: Combined reading of Contrast Enhanced and Diffusion Weighted Magnetic Resonance Imaging by using a simple sum score.
abstract: OBJECTIVE
  To improve specificity of breast MRI by integrating Apparent Diffusion Coefficient (ADC) values with contrast enhanced MRI (CE-MRI) using a simple sum score.
  
  
  METHODS
  Retrospective analysis of a consecutive series of patients referred to breast MRI at 1.5 T for further workup of breast lesions. Reading results of CE-MRI were dichotomized into score 1 (suspicious) or 0 (benign). Lesion's ADC-values (in *10-3 mm2/s) were assigned two different scores: ADC2: likely malignant (score +1, ADC ≤ 1), indeterminate (score 0, ADC >1- ≤ 1.4) and likely benign (score -1, ADC > 1.4) and ADC1: indeterminate (score 0, ADC ≤ 1.4) and likely benign (score -1, ADC > 1.4). Final added CE-MRI and ADC scores >0 were considered suspicious. Reference standard was histology and imaging follow-up of >24 months. Diagnostic parameters were compared using McNemar tests.
  
  
  RESULTS
  A total of 150 lesions (73 malignant) were investigated. Reading of CE-MRI showed a sensitivity of 100 % (73/73) and a specificity of 81.8 % (63/77). Additional integration of ADC scores increased specificity (ADC2/ADC1, P = 0.008/0.001) without causing false negative results.
  
  
  CONCLUSIONS
  Using a simple sum score, ADC-values can be integrated with CE-MRI of the breast, improving specificity. The best approach is using one threshold to exclude cancer.
  
  
  CONCLUSIONS
  ADC is used to assign levels of suspicion to breast lesions. ADC values >1.4 *10 (-3)   mm (2) /s are likely benign and effectively rule out malignancy. ADC values below ≤1*10 (-3)   mm (2) /s) are likely malignant but may be false positive. CE-MRI (+1: suspicious, 0: benign) and ADC (0: indeterminate, -1: benign) scores are added. Sum scores >0 should be biopsied.
authors.affiliation: Department of Anesthesia, Critical Care and Pain Medicine, Medical University of Vienna (AKH), Waehringer-Guertel 18-20, A-1090, Vienna, Austria.
authors.forename: Anja
authors.initials: A
authors.lastname: Baltzer
authors.affiliation: Department of Neuroradiology, University Hospital Erlangen, Schwabachanlage 6, D-91054, Erlangen, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Dietzel
authors.affiliation: Institute of Clinical Radiology and Nuclear Medicine, Theodor-Kutzer-Ufer 1-3, D-68167, Mannheim, Germany.
authors.forename: Clemens G
authors.initials: CG
authors.lastname: Kaiser
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna (AKH), General Hospital Vienna, Waehringer-Guertel 18-20, A-1090, Vienna, Austria. pascal.baltzer@meduniwien.ac.at.
authors.forename: Pascal A
authors.initials: PA
authors.lastname: Baltzer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001940:Breast / Q000473:pathology*; D001943:Breast Neoplasms / Q000473:pathology*; D003287:Contrast Media; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005260:Female; D006801:Humans; D061705:Image-Guided Biopsy; D008875:Middle Aged; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D003287:Contrast Media
keywords: Breast neoplasms; Contrast enhanced MRI; Diffusion Weighted Imaging; MR imaging; Sensitivity and Specificity