Table 3.

ORs (95% CI) of developing subsequent breast cancer according to tertiles of the percentage of p27+, ER+, and Ki67+ in normal breast tissue among premenopausal women in the NHS and the NHSII

CaseControlOR (95% CI)
Percentage of p27+ cells
 <9.0%18581.0 (Ref)
 9.0%–24.9%17520.97 (0.44–2.12)
 ≥25.0%14620.72 (0.32–1.61)
Per 1% increase0.99 (0.97–1.02)
Ptrend0.60
Percentage of ER+ cells
 <2.9%17531.0 (Ref)
 2.9%–9.1%17521.06 (0.47–2.35)
 ≥9.2%12590.74 (0.32–1.74)
Per 1% increase0.99 (0.96–1.03)
Ptrend0.68
Percentage of Ki67+ cells
 <0.5%2541.0 (Ref)
 0.5%–2.1%174112.1 (2.56–57.4)
 ≥2.2%164210.1 (2.12–48.0)
Per 1% increase1.10 (1.01–1.19)
Ptrend0.02
Percentage of p27+ER+ cells
 <1.6%17531.0 (Ref)
 1.6%–5.2%17521.52 (0.69–3.32)
 ≥5.2%12590.61 (0.25–1.50)
Per 1% increase0.98 (0.92–1.04)
Ptrend0.52
Percentage of p27+Ki67+ cells
 <0.1%16541.0 (Ref)
 0.1–0.5%20489.71 (2.65–35.6)
 ≥0.5%10623.47 (1.43–8.42)
Per 1% increase1.31 (1.01–1.70)
Ptrend0.04

NOTE: Adjusted for matching factors only: age at diagnosis (continuous, years), calendar year of biopsy (<1970, 1970–1980, 1980+), time since biopsy (continuous, years). Numbers in bold and italic are statistically significant.