Objective: To assess the relationships among circulating insulin-like growth factor-1 (IGF-1), IGF binding protein-3 (IGFBP-3), prostate-specific antigen (PSA) and C-reactive protein (an indicator of inflammatory systemic response) in patients with prostate disease and cancer of different stages.
Patients and methods: Circulating IGF-1, IGFBP-3, PSA and C-reactive protein concentrations were measured in patients with BPH (17) or stages T1/T2 (15), T3/T4 (16) and metastatic prostate cancer (12 patients).
Results: IGF-1 and IGFBP-3 concentrations were similar between patients with BPH and those with cancer, and there was no difference between the groups with cancer. In the latter patients there was a significant correlation between age and IGFBP-3 concentrations (r = -0.400, P = 0.008) but not with IGF-1 concentrations. Controlling for age, there were significant partial correlations between C-reactive protein and IGF-1 (r = -0.412, P = 0.008) and IGFBP-3 (r = -0.277, P = 0.05).
Conclusions: These results indicate that circulating IGF-1 and IGFBP-3 concentrations do not change with disease stage in prostate cancer, but that they decrease with an increase in the systemic inflammatory response.