Insulin-like growth factor (IGF)-I, IGF binding protein-3, and prostate cancer: correlation with Gleason score.

Introduction: Non-androgenic growth factors are involved in the growth regulation of prostate cancer (PCa).

Objective: This is the first Brazilian study to correlate, in a population of patients operated for PCa, PSA, total testosterone, insulin-like growth factor-I (IGF-I) and insulin-like growth factor-binding protein-3 (IGFBP-3) with Gleason score and to compare with a control group with benign prostate hyperplasia (BPH).

Materials And Methods: This retrospective single-center study included 49 men with previously diagnosed PCa and 45 with previously diagnosed BPH. PSA, testosterone, IGF-I, IGFBP-3 were determined in both groups.

Results: PSA and IGFBP-3 levels were significantly higher in the PCa group as compared to the BPH group (p < 0.001 and p=0.004, respectively). There was a significant difference when we compared the PSA before surgery (p < 0.001) and at the inclusion in the study (p < 0.001) and IGFBP3 (0.016) among patients with Gleason < 7, ≥7 and BPH. In the PCa group, PSA, testosterone, IGF-I and IGFBP-3 levels were comparable between Gleason < 7 and ≥7.

Conclusions: Our data suggest that in localized PCa, the quantification of PSA and, not of IGF-1, may provide independent significant information in the aggressiveness. IGFBP-3 could be a biochemical marker of disease control in PCa patients.