title: Diffusion-weighted imaging reflects variable cellularity and stromal density present in breast fibroadenomas.
abstract: OBJECTIVE
  To determine the underlying histopathologic features influencing apparent diffusion coefficient (ADC) values of breast fibroadenomas.
  
  
  METHODS
  Biopsy-proven fibroadenomas (n=26) initially identified as suspicious on breast magnetic resonance imaging (MRI) were retrospectively evaluated. Histopathologic assessments of lesion cellularity and stromal type were compared with ADC measures on diffusion-weighted MRI.
  
  
  RESULTS
  Presence of epithelial hyperplasia (increased cellularity) and dense collagenous stroma were both significantly associated with lower lesion ADC values (P=.02 and .004, respectively).
  
  
  CONCLUSIONS
  Variations in epithelial cellularity and stromal type influence breast lesion ADC values and may explain the wide range of ADC measures observed in benign fibroadenomas.
authors.affiliation: Department of Radiology, Seattle Cancer Care Alliance, University of Washington School of Medicine, 825 Eastlake Ave. E., G3-200, Seattle, WA 98109-1023, USA. Electronic address: parsian@uw.edu.
authors.forename: Sana
authors.initials: S
authors.lastname: Parsian
authors.affiliation: Department of Anatomic Pathology, University of Washington School of Medicine, 1959 NE Pacific St., Box 356100, Seattle, WA 98195, USA. Electronic address: ngiannak@ualberta.ca.
authors.forename: Nadia V
authors.initials: NV
authors.lastname: Giannakopoulos
authors.affiliation: Department of Radiology, Seattle Cancer Care Alliance, University of Washington School of Medicine, 825 Eastlake Ave. E., G3-200, Seattle, WA 98109-1023, USA. Electronic address: hrahbar@uw.edu.
authors.forename: Habib
authors.initials: H
authors.lastname: Rahbar
authors.affiliation: Department of Anatomic Pathology, University of Washington School of Medicine, 1959 NE Pacific St., Box 356100, Seattle, WA 98195, USA. Electronic address: mararend@uw.edu.
authors.forename: Mara H
authors.initials: MH
authors.lastname: Rendi
authors.affiliation: Department of Biostatistics & Biomathematics, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave N, M2-B500, Seattle, WA 98109, USA. Electronic address: xchai@fredhutch.org.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Chai
authors.affiliation: Department of Radiology, Seattle Cancer Care Alliance, University of Washington School of Medicine, 825 Eastlake Ave. E., G3-200, Seattle, WA 98109-1023, USA. Electronic address: scp3@u.washington.edu.
authors.forename: Savannah C
authors.initials: SC
authors.lastname: Partridge
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D001940:Breast / Q000000981:diagnostic imaging* / Q000473:pathology; D000071060:Breast Density; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D038524:Diffusion Magnetic Resonance Imaging; D005189:False Positive Reactions; D005260:Female; D018226:Fibroadenoma / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008875:Middle Aged; D012189:Retrospective Studies
keywords: Apparent diffusion coefficient (ADC); Cellularity; Diffusion-weighted imaging (DWI); Fibroadenomas; Stroma