Table 2.

Distribution of breast cancer intrinsic subtypes from PAM50 gene expression assay in the population-based LACE and Pathways studies, in a subcohort overall and by clinicopathologic categories

Clinicopathologic categorya
SubcohortLow-risk endocrine +High-risk endocrine +HER2+, endocrine −Triple negative
n = 1,319n = 298n = 480n = 138n = 405
PAM50 subtype%95% CI%95% CISens/Specb%95% CISens/Specb%95% CISens/Specb%95% CISens/Specb
Luminal A53.149.8–56.576.571.4–81.00.74/0.7440.534.5–––5.2
Luminal B20.517.7–23.614.811.2–19.336.230.6–42.30.59/0.737.44.0––7.2
  • aClinicopathologic categories (columns), defined in methods, are based on ER and PR expression, as determined by IHC, HER2 overexpression by IHC, and/or FISH, and tumor grade.

  • bSensitivity and specificity, treating clinicopathologic category as test and the most similar PAM50 subtype classification as the gold standard.