title: Breast density in relation to risk of ductal carcinoma in situ of the breast in women undergoing screening mammography.
abstract: OBJECTIVE
  To examine the association between breast density and risk of breast ductal carcinoma in situ (DCIS).
  
  
  METHODS
  We assessed breast density in relation to DCIS risk using combined data from statewide mammography registries in NH and VT. The prospective analyses were based on 572 DCIS cases arising in 154,936 women (58,496 premenopausal and 96,440 postmenopausal). Women in the study were followed on average 4.1 years. Breast density was scored by community radiologists using BIRADS categories (fatty, scattered density, heterogeneous density, extreme density).
  
  
  RESULTS
  In premenopausal women, based on 157 cases, the RR for DCIS risk were 0.29 (95% CI: 0.0.04, 2.24) for fatty breasts, 2.06 (95% CI: 1.39, 3.05) for heterogeneous density, and 2.40 (95% CI: 1.47, 3.91) for extreme density, relative to scattered density. In postmenopausal women, based on 369 cases, the RR for DCIS risk were 0.58 (95% CI: 0.37, 0.93) for fatty breasts, 1.41 (95% CI: 1.12, 1.78) for heterogeneous density, and 1.49 (95% CI: 0.93, 2.37) for extreme density, relative to scattered density. The possible interaction between breast density and menopausal status in relation to DCIS risk was not statistically significant.
  
  
  CONCLUSIONS
  We observed an association between breast density and DCIS risk. Although the association seemed stronger in premenopausal women, there was no evidence of an interaction involving breast density and menopausal status.
authors.affiliation: Department of Community & Family Medicine, Dartmouth Medical School, Norris Cotton Cancer Center, Hanover, NH, USA.
authors.forename: Todd A
authors.initials: TA
authors.lastname: MacKenzie
authors.forename: Linda
authors.initials: L
authors.lastname: Titus-Ernstoff
authors.forename: Pamela M
authors.initials: PM
authors.lastname: Vacek
authors.forename: Berta
authors.initials: B
authors.lastname: Geller
authors.forename: Julia E
authors.initials: JE
authors.lastname: Weiss
authors.forename: Martha E
authors.initials: ME
authors.lastname: Goodrich
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Carney
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001940:Breast / Q000033:anatomy & histology*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D005006:Ethnicity / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008327:Mammography / Q000706:statistics & numerical data*; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D017698:Postmenopause; D017697:Premenopause; D012307:Risk Factors; D013997:Time Factors