title: Atypical hyperplasia, proliferative fibrocystic change, and exogenous hormone use.
abstract: BACKGROUND
  The association between breast cancer development and exogenous hormone use (EHU) is suggested by indirect clinical evidence. We undertook this study to better define the relationship that EHU has with proliferative fibrocystic change (PFC) and atypical hyperplasia (AH).
  
  
  METHODS
  Women diagnosed with AH without associated carcinoma from January 1990 to December 1999 were compared with control subjects who underwent breast biopsy procedures during the same interval and who were diagnosed with either a proliferative fibrocystic change (PFC) or a nonproliferative fibrocystic change (NPFC). EHU was defined as the use of estrogen or progesterone taken together or separately within 3 months of biopsy.
  
  
  RESULTS
  EHU was significantly higher in patients with AH compared with women with NPFC (P =.01). This observation was also significant if all proliferative change (both AH and PFC) was compared with NPFC (P =.03); it was not significant when PFC alone was compared with NPFC. No significant difference in EHU was demonstrated between women with AH and those with PFC.
  
  
  CONCLUSIONS
  There is strong association between AH and EHU. These results support the theory that a continuum exists between hyperplasia and carcinoma and that EHU may influence the transition from one to the other in an undefined subset of women. We encourage our patients with AH to discontinue EHU.
authors.affiliation: Department of Surgery, Hennepin County Medical Center, University of Minnesota Medical School, Minneapolis, Minn 55415, USA.
authors.forename: R T
authors.initials: RT
authors.lastname: Zera
authors.forename: D
authors.initials: D
authors.lastname: Danielson
authors.forename: J M
authors.initials: JM
authors.lastname: Van Camp
authors.forename: B
authors.initials: B
authors.lastname: Schmidt-Steinbrunn
authors.forename: J
authors.initials: J
authors.lastname: Hong
authors.forename: M
authors.initials: M
authors.lastname: McCoy
authors.forename: W R
authors.initials: WR
authors.lastname: Anderson
authors.forename: B M
authors.initials: BM
authors.lastname: Linzie
authors.forename: J L
authors.initials: JL
authors.lastname: Rodriguez
mesh_terms: D000328:Adult; D000368:Aged; D001940:Breast / Q000187:drug effects* / Q000473:pathology; D004967:Estrogens / Q000009:adverse effects*; D005260:Female; D005348:Fibrocystic Breast Disease / Q000139:chemically induced*; D006801:Humans; D006965:Hyperplasia; D008875:Middle Aged; D011374:Progesterone / Q000009:adverse effects*
chemical_list: D004967:Estrogens; D011374:Progesterone