title: Potential impact of preoperative magnetic resonance imaging of the breast on patient selection for accelerated partial breast irradiation.
abstract: OBJECTIVE
  Accelerated partial breast irradiation (APBI) after breast-conserving therapy is currently under investigation in prospective randomized studies. Multifocality and multicentricity are exclusion criteria for APBI. Preoperative breast magnetic resonance imaging (MRI) can detect ipsilateral and contralateral invasive tumor foci or ductal carcinoma in situ in addition to conventional diagnostic methods (clinical examination, mammography, and ultrasonography). The objective of this retrospective study was to evaluate the impact of preoperative MRI on patient selection for APBI.
  
  
  METHODS
  From 2002 to 2007, a total of 579 consecutive, nonselected patients with newly diagnosed early-stage breast cancer received preoperative breast MRI in addition to conventional imaging studies at the Bonn University Breast Cancer Center. In retrospect, 113 patients would have met the criteria for APBI using conventional imaging workup (clinical tumor size ≤3 cm; negative axillary lymph node status; unifocal disease; no evidence of distant metastases; no invasive lobular carcinoma, ductal and lobular carcinoma in situ, or Paget's disease). We analyzed the amount of additional ipsilateral and contralateral tumor foci detected by MRI.
  
  
  RESULTS
  MRI detected additional tumor foci in 8.8% of patients eligible for APBI (11 tumor foci in 10 of 113 patients), either ipsilateral (n = 7, 6.2%) or contralateral (n = 4, 3.5%). In 1 patient, MRI helped detect additional tumor focus both ipsilaterally and contralaterally.
  
  
  CONCLUSIONS
  Preoperative breast MRI is able to identify additional tumor foci in a clinically relevant number of cases in this highly selected group of patients with low-risk disease and may be useful in selecting patients for APBI.
authors.affiliation: Department of Obstetrics and Gynecology and Center of Integrated Oncology, University of Bonn, Bonn, Germany. marietta.kuehr@ukb.uni-bonn.de
authors.forename: Marietta
authors.initials: M
authors.lastname: Kühr
authors.forename: Matthias
authors.initials: M
authors.lastname: Wolfgarten
authors.forename: Marco
authors.initials: M
authors.lastname: Stölzle
authors.forename: Claudia
authors.initials: C
authors.lastname: Leutner
authors.forename: Tobias
authors.initials: T
authors.lastname: Höller
authors.forename: Simone
authors.initials: S
authors.lastname: Schrading
authors.forename: Christiane
authors.initials: C
authors.lastname: Kuhl
authors.forename: Hans
authors.initials: H
authors.lastname: Schild
authors.forename: Walther
authors.initials: W
authors.lastname: Kuhn
authors.forename: Michael
authors.initials: M
authors.lastname: Braun
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D001940:Breast / Q000473:pathology; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D015412:Mastectomy, Segmental; D008875:Middle Aged; D018579:Patient Selection; D011300:Preoperative Care / Q000379:methods; D011878:Radiotherapy / Q000379:methods; D012189:Retrospective Studies; D047368:Tumor Burden