['C-reactive protein (CRP) is a sensitive marker of inflammation that has been linked with prognosis in various solid tumours. In the present study, we analysed the prognostic relevance of elevated plasma CRP levels in prostate cancer patients treated with radiotherapy.', 'A total of 261 prostate cancer patients treated with 3D-conformal radiotherapy were evaluated retrospectively. Cancer specific survival (CSS), overall survival (OS) and clinical disease-free survival (DFS) were assessed using Kaplan-Meier analysis. To evaluate the independent prognostic significance of CRP plasma levels, multivariate Cox regression models were applied.', 'The median follow-time was 80months. Applying receiver operating characteristics (ROC) analysis, the optimal cut-off level for the plasma CRP was 8.6mgl(-1). An elevated CRP level was associated with decreased CSS in univariate (hazard ratio (HR) 3.36, 95% confidence interval (CI) 1.42-7.91; p=0.006) and multivariate analysis (HR 4.31, 95% CI 1.22-15.1; p=0.023). Furthermore, a significant association with OS was detected in univariate (HR 2.69, 95% CI 1.57-4.59; p<0.001) and multivariate analyses (HR 3.24, 95% CI 1.84-5.71, p<0.001). Multivariate analysis also showed a significant association between plasma CRP and clinical DFS (HR 2.07, 95% CI 1.02-4.17; p=0.043).'] Is the elevated C-reactive protein level associated with poor prognosis in prostate cancer patients treated with radiotherapy?