Clinical Implications of C-Reactive Protein as a Prognostic Marker in Advanced Cancer Patients in Palliative Care Settings

Abstract

Context: Plasma C-reactive protein (CRP) levels are elevated in patients with advanced cancer.

Objectives: To investigate CRP as a prognostic marker in palliative settings.

Methods: This multicenter prospective cohort study comprised 2426 patients. Laboratory data were obtained at baseline, and all patients were followed until death or six months after their enrollment. A total of 1511 patients were eligible for the analyses. They were divided into four groups: low-CRP (CRP < 1 mg/dL), moderate-CRP (1 ≤ CRP <5 mg/dL), high-CRP (5 ≤ CRP <10 mg/dL), and very high-CRP (10 mg/dL ≤ CRP) groups. Survival was investigated by the Kaplan-Meier method with the log-rank test. The 30-, 60-, and 90-day mortality rates were tested by Chi-squared tests. Univariate- and multivariate-adjusted hazard ratios (HRs) and 95% CIs in each group were calculated using Cox proportional hazard models.

Results: Survival rate decreased and mortality rate increased with increasing CRP level. The differences in survival and 30-, 60-, and 90-day mortality rates among the groups were statistically significant (P < 0.001). Baseline CRP level was significantly associated with a higher risk of mortality after adjustment for age, gender, primary tumor site, metastasis, chemotherapy, Eastern Cooperative Oncology Group Performance Status, and setting of care (moderate-CRP: HR 1.47 [95% CI 1.24-1.73], high-CRP: HR 2.09 [95% CI 1.74-2.50], and very high-CRP: HR 2.55 [95% CI 2.13-3.05] vs. low-CRP).

Conclusion: Clear dose-effect relationships between elevated CRP levels and prognoses indicate that CRP could be useful in predicting prognoses in patients with advanced cancer.

Keywords: C-reactive protein; advanced cancer patients; palliative setting; prognostic marker.