title: [Usual hyperplasia, atypical hyperplasia and carcinoma-in-situ of breast: a morphologic study].
abstract: OBJECTIVE
  To study the morphologic classification of mammary ductal hyperplasia, and its criteria and the significance in distinguishing atypical hyperplasia from carcinoma-in-situ.
  
  
  METHODS
  The clinicopathologic features of 300 cases of hyperplasia of breast were reviewed. Whole-organ H&E sections were also available in 86 cases of breast carcinoma. The occurrence of atypical hyperplasia in adjacent breast tissue was assessed.
  
  
  RESULTS
  Fibroadenomatoid changes were typically observed in the 21-30 age groups and atypical hyperplasia occurred more frequently in 40-60 age groups. Amongst the hyperplastic cases, cystic diseases of the breast were noted in only 6%. In contrast, fibroadenomatoid changes were more common (25.4%). Atypical ductal hyperplasia occurred in adjacent breast tissue of 65.1% of the carcinoma cases. The incidence was higher (74.9%) if the main lesion was ductal carcinoma-in-situ.
  
  
  CONCLUSIONS
  There is a close association between atypical hyperplasia and breast carcinoma. It is prudent to distinguish between usual and atypical hyperplasia. Morphologic differentiation between atypical ductal hyperplasia and ductal carcinoma-in-situ may sometimes be difficult.
authors.affiliation: Department of Pathology, People's Hospital, Peking University, Beijing 100044, China.
authors.forename: Xiu
authors.initials: X
authors.lastname: Kan
authors.forename: Dan-hua
authors.initials: DH
authors.lastname: Shen
authors.forename: Bin
authors.initials: B
authors.lastname: Shi
authors.forename: Jing-sheng
authors.initials: JS
authors.lastname: He
mesh_terms: D000328:Adult; D001940:Breast / Q000473:pathology*; D001943:Breast Neoplasms / Q000473:pathology*; D002278:Carcinoma in Situ / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000473:pathology; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D018226:Fibroadenoma / Q000473:pathology; D006801:Humans; D006965:Hyperplasia / Q000473:pathology; D008875:Middle Aged; D011230:Precancerous Conditions / Q000473:pathology*