C-Reactive Protein and Risk of Breast Cancer

Abstract
Chronic inflammation is hypothesized to be associated with breast cancer development. However, data evaluating the association between C-reactive protein (CRP), a marker of systemic inflammation, and breast cancer risk are sparse. In the Women's Health Study, 27,919 apparently healthy women aged 45 years and older who were free of cancer and cardiovascular disease had plasma CRP levels measured at baseline. During a mean of 10 years of follow-up, a total of 892 women developed invasive breast cancer. All statistical tests were two-sided. Baseline plasma CRP level was not statistically significantly associated with breast cancer risk (highest versus lowest quintile of CRP, multivariable hazard ratio = 0.90, 95% confidence interval = 0.71 to 1.16; P(trend) = .19; crude incidence rates: 273 versus 305 per 100,000 person-years). Our data suggest that baseline plasma CRP levels are not associated with the increased risk of breast cancer in apparently healthy women.