title: The ratio of atypical ductal hyperplasia foci to core numbers in needle biopsy: a practical index predicting breast cancer in subsequent excision.
abstract: BACKGROUND
  Although core needle biopsy (CNB) is considered to be the standard technique for histological diagnosis of breast lesions, it is less reliable for diagnosing atypical ductal hyperplasia (ADH). We therefore assessed the characteristics of CNB-diagnosed ADH that are more likely to be associated with more advanced lesions on subsequent surgical excision.
  
  
  METHODS
  We retrospectively examined 239 consecutive CNBs, 127 of which were diagnosed as ADH following surgical excision, performed at Asan Medical Center between 1995 and 2010. Archival slides were analyzed for the number of cores per specimen, the number of ADH foci, and the ratio of ADH foci to number of cores (FC ratio).
  
  
  RESULTS
  We found that ADH foci in 3 or more cores (p=0.003) and the presence of ADH in 3 or more foci (p=0.002) were correlated with malignancy following excision lesion. Moreover, an FC>1.1 was significantly associated with malignancy in the subsequent excision (p=0.000).
  
  
  CONCLUSIONS
  Including the number of ADH foci, the number of cores involved according to ADH, FC ratio, and histologic type in a pathology report of CNB may help in making clinical decisions about surgical excision.
authors.affiliation: Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jeong-Ju
authors.initials: JJ
authors.lastname: Lee
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Lee
authors.forename: Jun
authors.initials: J
authors.lastname: Kang
authors.forename: Jeong-Hyeon
authors.initials: JH
authors.lastname: Jo
authors.forename: Gyungyub
authors.initials: G
authors.lastname: Gong
keywords: Atypical ductal hyperplasia; Core needle biopsy; Predictive pathologic factor