Skip to main content

Table 2 Association between mammographic density estimates on the enrollment (screen-film) mammograms and risk of breast cancer in the Mayo Mammography Health Study cohort (2003 to 2009)

From: The influence of mammogram acquisition on the mammographic density and breast cancer association in the mayo mammography health study cohort

  Number of cases (total n= 272)a Number of person-years (total n= 9,958.8)b, c Multivariate adjusted hazard ratio (95% CI)c
Percent density    
   0.0-5.0 43 2,193.8 1.00 (Ref.)
   5.1-15.0 79 2,746.1 2.02 (1.37, 2.97)
   15.1-25.0 59 2,386.4 2.03 (1.32, 3.11)
   25.1+ 91 2,632.5 3.80 (2.46, 5.86)
   P trend    < 0.001
BI-RADS lexicon    
   1: Almost entirely fat 44 2,181.6 1.00 (Ref.)
   2: Scattered fibroglandular densities 111 3,904.5 1.61 (1.13, 2.29)
   3: Heterogeneously dense 94 3,210.1 2.02 (1.38, 2.95)
   4: Extremely dense 23 662.7 2.96 (1.73, 5.07)
   P trend    < 0.001
  1. Analyses adjusted for age, menopausal status, post-menopausal hormone use, and body mass index. aForty-six cases were excluded from the original 318 cases for the following reasons: digital mammogram (13), implants (12), and inability to read density (21). Percent density and BI-RADS (Breast Imaging Reporting and Data System) analyses were restricted to the same women. bThree hundred two in the subcohort were excluded for the following reasons: digital mammogram (123), implants (62), and inability to read density (117). Percent density and BI-RADS analyses were restricted to the same women (272 cases and 1,957 in the subcohort).