title: A simple classification system (the Tree flowchart) for breast MRI can reduce the number of unnecessary biopsies in MRI-only lesions.
abstract: OBJECTIVE
  To assess whether using the Tree flowchart obviates unnecessary magnetic resonance imaging (MRI)-guided biopsies in breast lesions only visible on MRI.
  
  
  METHODS
  This retrospective IRB-approved study evaluated consecutive suspicious (BI-RADS 4) breast lesions only visible on MRI that were referred to our institution for MRI-guided biopsy. All lesions were evaluated according to the Tree flowchart for breast MRI by experienced readers. The Tree flowchart is a decision rule that assigns levels of suspicion to specific combinations of diagnostic criteria. Receiver operating characteristic (ROC) curve analysis was used to evaluate diagnostic accuracy. To assess reproducibility by kappa statistics, a second reader rated a subset of 82 patients.
  
  
  RESULTS
  There were 454 patients with 469 histopathologically verified lesions included (98 malignant, 371 benign lesions). The area under the curve (AUC) of the Tree flowchart was 0.873 (95% CI: 0.839-0.901). The inter-reader agreement was almost perfect (kappa: 0.944; 95% CI 0.889-0.998). ROC analysis revealed exclusively benign lesions if the Tree node was ≤2, potentially avoiding unnecessary biopsies in 103 cases (27.8%).
  
  
  CONCLUSIONS
  Using the Tree flowchart in breast lesions only visible on MRI, more than 25% of biopsies could be avoided without missing any breast cancer.
  
  
  CONCLUSIONS
  • The Tree flowchart may obviate >25% of unnecessary MRI-guided breast biopsies. • This decrease in MRI-guided biopsies does not cause any false-negative cases. • The Tree flowchart predicts 30.6% of malignancies with >98% specificity. • The Tree's high specificity aids in decision-making after benign biopsy results.
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
authors.forename: Ramona
authors.initials: R
authors.lastname: Woitek
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
authors.forename: Claudio
authors.initials: C
authors.lastname: Spick
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
authors.forename: Melanie
authors.initials: M
authors.lastname: Schernthaner
authors.affiliation: Clinical Institute of Pathology, Medical University of Vienna, Vienna, Austria.
authors.forename: Margaretha
authors.initials: M
authors.lastname: Rudas
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Kapetas
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
authors.forename: Maria
authors.initials: M
authors.lastname: Bernathova
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
authors.forename: Julia
authors.initials: J
authors.lastname: Furtner
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
authors.forename: Katja
authors.initials: K
authors.lastname: Pinker
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Helbich
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria. pascal.baltzer@meduniwien.ac.at.
authors.forename: Pascal A T
authors.initials: PAT
authors.lastname: Baltzer
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D001943:Breast Neoplasms / Q000145:classification* / Q000000981:diagnostic imaging; D003430:Cross-Sectional Studies; D003661:Decision Support Techniques; D005260:Female; D006801:Humans; D061705:Image-Guided Biopsy / Q000592:standards*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D019564:Unnecessary Procedures
keywords: Breast cancer; Image-guided biopsy; Magnetic resonance imaging; ROC curve; Scoring system