Prognostic Value of Pre-treatment Plasma C-Reactive Protein in Patients with Early-Stage Breast Cancer.

BACKGROUND: Breast cancer incidence is now the highest among all cancers and accountable for 6.6% of all cancer-related deaths worldwide. Studies of the prognostic utility of plasma CRP measurement in early-stage breast cancer have given discrepant results.

METHODS: We identified 6942 patients in the Danish Breast Cancer Cooperative Group database with early-stage breast cancer diagnosed between 2002 and 2016 who had a measure of pre-treatment plasma CRP. Outcomes were recurrence-free interval and survival for a period up to ten years. We analyzed associations with plasma CRP using Fine-Gray proportional sub-distribution hazards model with recurrence-free interval. Data on plasma CRP were analyzed per doubling of concentration and in relation to CRP levels of < 3 mg/L; 3-10 mg/L, and > 10 mg/L and stratified according to standard clinical parameters in sensitivity analyses.

RESULTS: A doubling of the plasma CRP concentration was associated with increased risk of recurrence (multivariate adjusted HR = 1.05, 95% CI 1.01;1.08) and shorter survival (HR = 1.13, 1.09;1.16) in multivariate analyses. Survival was shorter in patients with plasma CRP levels of 3-10 and > 10 vs. < 3 mg/L, with multivariate adjusted HRs of 1.30 (1.17;1.45) and 1.65 (1.39;1.95), respectively.

CONCLUSIONS: Elevated plasma CRP measured before treatment in patients with early-stage breast cancer is an independent biomarker of increased risk of recurrence and early death.

IMPACT: CRP measures before treatment might be used to individualize follow-up of patients with early-stage breast cancer.