title: Response to neoadjuvant treatment of invasive ductal breast carcinomas including outcome evaluation: MRI analysis by an automatic CAD system in comparison to visual evaluation.
abstract: BACKGROUND
  The aim of this study was to evaluate imaging-based response to standardized neoadjuvant chemotherapy (NACT) regimen by dynamic contrast-enhanced magnetic resonance mammography (DCE-MRM), whereas MR images were analyzed by an automatic computer-assisted diagnosis (CAD) system in comparison to visual evaluation. MRI findings were correlated with histopathologic response to NACT and also with the occurrence of metastases in a follow-up analysis.
  
  
  METHODS
  Fifty-four patients with invasive ductal breast carcinomas received two identical MRI examinations (before and after NACT; 1.5T, contrast medium gadoteric acid). Pre-therapeutic images were compared with post-therapeutic examinations by CAD and two blinded human observers, considering morphologic and dynamic MRI parameters as well as tumor size measurements. Imaging-assessed response to NACT was compared with histopathologically verified response. All clinical, histopathologic, and DCE-MRM parameters were correlated with the occurrence of distant metastases.
  
  
  RESULTS
  Initial and post-initial dynamic parameters significantly changed between pre- and post-therapeutic DCE-MRM. Visually evaluated DCE-MRM revealed sensitivity of 85.7%, specificity of 91.7%, and diagnostic accuracy of 87.0% in evaluating the response to NACT compared to histopathology. CAD analysis led to more false-negative findings (37.0%) compared to visual evaluation (11.1%), resulting in sensitivity of 52.4%, specificity of 100.0%, and diagnostic accuracy of 63.0%. The following dynamic MRI parameters showed significant associations to occurring metastases: Post-initial curve type before NACT (entire lesions, calculated by CAD) and post-initial curve type of the most enhancing tumor parts after NACT (calculated by CAD and manually).
  
  
  CONCLUSIONS
  In the accurate evaluation of response to neoadjuvant treatment, CAD systems can provide useful additional information due to the high specificity; however, they cannot replace visual imaging evaluation. Besides traditional prognostic factors, contrast medium-induced dynamic MRI parameters reveal significant associations to patient outcome, i.e. occurrence of distant metastases.
authors.affiliation: Institute of Diagnostic and Interventional Radiology, SRH Clinic Gera , Gera , Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Böttcher
authors.forename: Diane M
authors.initials: DM
authors.lastname: Renz
authors.forename: Dirk-Michael
authors.initials: DM
authors.lastname: Zahm
authors.forename: Alexander
authors.initials: A
authors.lastname: Pfeil
authors.forename: Eva M
authors.initials: EM
authors.lastname: Fallenberg
authors.forename: Florian
authors.initials: F
authors.lastname: Streitparth
authors.forename: Martin H
authors.initials: MH
authors.lastname: Maurer
authors.forename: Bernd
authors.initials: B
authors.lastname: Hamm
authors.forename: Florian J
authors.initials: FJ
authors.lastname: Engelken
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000175:diagnosis / Q000188:drug therapy* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis / Q000188:drug therapy* / Q000473:pathology; D015331:Cohort Studies; D003520:Cyclophosphamide / Q000008:administration & dosage; D003936:Diagnosis, Computer-Assisted; D000077143:Docetaxel; D004317:Doxorubicin / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008327:Mammography; D008408:Mastectomy; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D043823:Taxoids / Q000008:administration & dosage; D016896:Treatment Outcome
chemical_list: D043823:Taxoids; D000077143:Docetaxel; D004317:Doxorubicin; D003520:Cyclophosphamide