Background: IL-6 has been reported to be a significant prognostic factor for prostate cancer and induces synthesis of C-reactive protein (CRP) by hepatocytes. The present study was undertaken to evaluate the clinical value of serum CRP in prostate cancer patients with metastases.
Methods: The prognostic significance of serum CRP as well as tumor histology, extent of disease (EOD) on bone scan, serum levels of prostate-specific antigen (PSA) and alkaline phosphatase (ALP) and hemoglobin was assessed using Cox's proportional hazards model analyses in 126 prostate cancer patients with metastases treated with endocrine therapy.
Results: Serum levels of CRP, PSA and ALP significantly increased and hemoglobin significantly decreased with advancing EOD grade. Univariate analysis demonstrated that EOD, CRP, PSA, ALP, hemoglobin and tumor histology are significantly associated with disease-specific survival. Multivariate analysis demonstrated that serum CRP and EOD were significant prognostic factors. The 5-year survival rates in low-risk patients (CRP < or = 0.15 mg/dl and EOD < or = 1) and high-risk patients (CRP > 0.15 mg/dl and EOD > or = 2) were 74 and 24%, respectively.
Conclusion: These results indicate that a combination of serum CRP and EOD can identify patients with a poor prognosis who may be candidates for innovative treatments among prostate cancer patients with metastases.