Correlation of preoperative plasma IGF-I levels with pathologic parametersand progression in patients undergoing radical prostatectomy

Objectives. To test whether preoperative insulin-like growth factor (IGF)-I levels could predict pathologic stage and prognosis of prostate cancer in patients undergoing radical prostatectomy. Methods. The study group consisted of 120 consecutive patients who underwen t radical prostatectomy for clinically localized prostate cancer. Preoperat ive plasma IGF-I levels were measured using the DSL-IGF-I Elisa assay. Surg ically removed prostate specimens were analyzed pathologically, using a who le-mount step-section technique. Preoperative plasma IGF-I levels were comp ared with final pathologic parameters and with prostate-specific antigen (P SA) progression-free survival. Preoperative IGF-I levels in this cohort wer e also compared with IGF-I levels measured in 20 healthy men without any ca ncer and in 10 men with untreated, metastatic prostate cancer. Results. Plasma IGF-I levels predicted neither organ-confined disease (P = 0.5611) nor the risk of PSA progression (P = 0.8125) at a median follow-up of 48.6 months after prostatectomy. Furthermore, IGF-I levels did not corre late with preoperative PSA level (P = 0.2811) or final Gleason score (P = 0 .4906). IGF-I levels in radical prostatectomy patients were not significant ly higher than those in healthy subjects or in patients with metastatic dis ease (mean 156.7 +/- 66 ng/mL, 148.6 +/- 49 ng/mL, and 148.6 +/- 93 ng/mL, respectively; P = 0.8442). Conclusions. Circulating IGF-I levels may predict the future risk of develo ping prostate cancer, but our study found no association with other establi shed markers of biologically aggressive disease or with disease progression in patients with clinically localized prostate cancer. UROLOGY 56: 423-429 , 2000. (C) 2000, Elsevier Science Inc.