The significance of serum levels of insulin-like growth factor-1 in patients with prostate cancer.
OBJECTIVE
To compare the serum levels of insulin-like growth factor-1 (IGF-1) in patients with prostate cancer and in control patients with no malignancy, and to evaluate any possible influence of testicular androgen withdrawal on the level of IGF-1 in patients with prostate cancer.


METHODS
IGF-1 was measured in serum samples from 238 patients using both a chemiluminescence method and a radio-immunoassay. From a subgroup of 19 patients presenting with newly diagnosed carcinoma of the prostate, IGF-1 and testosterone values were measured before and during the course of testicular androgen withdrawal, achieved by the administration of luteinizing hormone-releasing hormone (LHRH) analogues combined with anti-androgens.


RESULTS
There were no significant differences in the mean serum levels of IGF-1 patients with and without prostate cancer (158.6 and 159.1 ng/mL, respectively). There were no significant differences in mean IGF-1 levels before and after antiandrogen therapy; the mean (median, SD, range) levels of testosterone (microg/L) and IGF-1 (ng/mL) before androgen withdrawal were 4.81 (4.84, 1.26, 3.11-6.93) and 157.1 (152.5, 26.7, 122.8-195. 1). After androgen withdrawal the corresponding values were 0.303 (0. 218, 0.24, 0.13-0.81) and 169.7 (31.7, 168.6, 124.9-227.6). A linear regression analysis (P = 0.76) and Spearman rank order correlation test (correlation coefficient -0.0613, P = 0.64) showed no association between levels of testosterone and IGF-1. Freeze and thaw cycles applied to the samples had no effect on the IGF-1 values measured.


CONCLUSIONS
There was no significant association between IGF-1 serum levels and prostate cancer. Short-term androgen withdrawal using LHRH analogues combined with anti-androgens had no effect on the levels of IGF-1.
Kurek
R
R
Department of Urology, Städtische Kliniken Offenbach, Germany.
Tunn
U W
UW
Eckart
O
O
Aumüller
G
G
Wong
J
J
Renneberg
H
H
D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000097:blood* / Q000188:drug therapy; D013739:Testosterone / Q000097:blood
D014408:Biomarkers, Tumor; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D007334:Insulin-Like Growth Factor I