Table 1.

Characteristics at time of diagnosis for LACE and Pathways breast cancer cohort participants and a subcohort subtyped by PAM50 gene expression–based classifier

LACE studyPathways studyCombined cohortSubcohorta
n = 2,135n = 2,172n = 4,307n = 1,319
%%%Raw %Weightedb %
Age at diagnosis (years)
Race and ethnicity
 White, non-Hispanic79.667.673.769.272.6
 Black or African American5.
 Asian or Pacific Islander6.510.
 American Indian or Alaska Native1.
 Other or missing1.
AJCC stage
Tumor size
 ≤2 cm65.064.564.859.766.1
 >2 cm35.031.533.240.333.9
Tumor markers from IHC/FISHc
 ERPR+ HER267.572.770.133.074.8
 ERPR+ HER2+11.19.310.226.09.8
 ERPR HER210.912.511.730.711.5
  • aSubjects with PAM50 subtyping results. The subcohort sample was chosen with the following selection probabilities by clinical subtype: ERPR+ HER2, 18%; ERPR+ HER2+, 100%; triple negative, 100%; ERPR HER2+, 100%.

  • bEstimated distribution of characteristics in the subcohort after accounting for stratified sampling.

  • cCategories based on tumor ER and PR expression, as determined by clinical IHC, and for HER2 overexpression by IHC and/or FISH. ERPR+ includes subjects with ER+ and/or PR+; ERPR includes subjects with both ER and PR.