Serum insulin-like growth factor-1 is not a useful masker of prostate cancer

Objective To determine whether the use of serum insulin-like growth factor 1 (IGF-1) levels is more efficient. than serum prostate specific antigen (P SA) levels in predicting prostate cancer in patients undergoing prostatic b iopsy. Patients and methods The study included 94 consecutive patients who require d transrectal ultrasonography (TRUS)-guided biopsies of their prostate and who had blood samples taken before their biopsies. These samples were then analysed for IGF-1 and PSA concentrations. Six prostatic biopsies were take n from each patient; they were assessed and a diagnosis made of prostate ca ncer or no malignancy. Results Thirty-seven patients were found to have prostate cancer and 57 had no evidence of malignancy. There was no statistical difference in serum IG F-1 levels between these groups. The PSA level and age of the patients diff ered significantly between the groups (both P<0.001). There was no correlat ion between IGF-1 and PSA levels, and even when the age difference in the g roups: was considered. there was still no significant relationship between IGF-1 levels and the incidence of prostate cancer. In patients with a PSA l evel of 4-20 mu g/L there was no statistically significant difference in IG F-1 levels between the groups, Conclusion Serum IGF-1 as a tumour marker does not help to predict patients with prostate cancer. PSA level and even age were better predictors of the presence of prostate cancer than were serum IGF-1 levels.