title: Follow-up MR imaging of PI-RADS 3 and PI-RADS 4 prostate lesions.
abstract: OBJECTIVE
  To determine the rate of malignancy after follow-up MR imaging of the prostate in PI-RADS 3 lesions without core biopsy and PI-RADS 4 lesions after negative initial core biopsy.
  
  
  METHODS
  We performed follow-up MRI in 46/72 (64%) patients with PI-RADS 3 lesions and 26/72 (36%) patients with PI-RADS 4 lesions in baseline MRI.
  
  
  RESULTS
  The rate of malignancy in PI-RADS 3 lesions was 4% (2/46) and in PI-RADS 4 lesions 69% (18/26).
  
  
  CONCLUSIONS
  Follow-up MRI for PI-RADS 3 lesions should be performed. For PI-RADS 4 lesions with initial negative biopsy we recommend an instant repeat core biopsy.
authors.affiliation: Radiologische Praxis, Ulm, Germany. Electronic address: ehauth@t-online.de.
authors.forename: Elke
authors.initials: E
authors.lastname: Hauth
authors.affiliation: Radiologische Praxis, Ulm, Germany. Electronic address: horstjaeger@t-online.de.
authors.forename: Horst
authors.initials: H
authors.lastname: Jaeger
authors.affiliation: Uropraxis, Ulm, Germany. Electronic address: hohmuth@uropraxis-ulm.de.
authors.forename: Horst
authors.initials: H
authors.lastname: Hohmuth
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital, Ulm, Germany. Electronic address: meinrad.beer@uniklinik-ulm.de.
authors.forename: Meinrad
authors.initials: M
authors.lastname: Beer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D062005:Biopsy, Large-Core Needle / Q000379:methods; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D011467:Prostate / Q000000981:diagnostic imaging / Q000473:pathology*; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology
keywords: Biopsy; Diagnosis; Follow-up; MR imaging; Prostate cancer