title: BI-RADS® 3 lesions at contrast-enhanced breast MRI: is an initial short-interval follow-up necessary?
abstract: BACKGROUND
  Magnetic resonance imaging (MRI) BI-RADS® 3 lesions should have a very high probability of being benign. To prove benignity most institutions do follow-up MRI.
  
  
  OBJECTIVE
  To evaluate the necessity of initial short-interval follow-up after 6 months as it is suggested for mammographic BI-RADS®3 lesions.
  
  
  METHODS
  We analyzed 163 consecutive MRI-BI-RADS® 3 lesions on follow-up MRI: 75 masses (46%), 67 foci (41.1%), and 21 (12.9%) non-mass-like enhancing lesions (NMLE).
  
  
  RESULTS
  During MRI follow-up (mean time, 563 days) 20% of the lesions disappeared, 23% decreased, 52% did not change, and 4.9% showed increase. All increasing lesions were biopsied (5 benign, 2 ductal carcinoma in situ, 1 invasive carcinoma). The rate of malignancy was 1.8%. All malignant lesions (1 mass, 1 focus, 1 NMLE) showed increase at initial follow-up after a mean interval of 190 days.
  
  
  CONCLUSIONS
  In this study the malignancy rate of MRI-BI-RADS® 3 lesions corresponded to mammographic BI-RADS® 3 lesions. Initial short-interval MRI should be suggested to identify malignant MRI-BI-RADS® 3 lesions.
authors: Department of Radiology, Diagnostic and Interventional Radiology, University Hospital Tuebingen, Germany.
authors: Sonja D
authors: SD
authors: Bahrs
authors: Astrid
authors: A
authors: Baur
authors: Valerie
authors: V
authors: Hattermann
authors: Markus
authors: M
authors: Hahn
authors: Ulrich
authors: U
authors: Vogel
authors: Claus D
authors: CD
authors: Claussen
authors: Katja C
authors: KC
authors: Siegmann-Luz
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003266:Continuity of Patient Care; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008327:Mammography; D008875:Middle Aged; D009942:Organometallic Compounds; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol; D019786:Gadolinium DTPA
keywords: Breast; MR imaging; screening