Insulin-like growth factor I is not a useful marker of prostate cancer in men with elevated levels of prostate-specific antigen.
High serum levels of insulin-like growth factor I (IGF-I) and low levels of IGF-binding protein-3 (IGFBP-3) have been shown to correlate with increased prostate cancer risk. To evaluate this, IGF-I, IGFBP-3, and prostate-specific antigen (PSA) were measured in serum from 665 consecutive men (179 with prostate cancer), aged 55-67 yr, with elevated serum prostate-specific antigen (PSA; > or = 4 microg/L) in a screening trial. Men in the highest quartile of IGF-I levels had an odds ratio (OR) for prostate cancer of 0.50 [95% confidence interval (CI) 0.26-0.97] when adjusting for serum IGFBP-3. IGFBP-3 itself was not significantly associated with prostate cancer risk (OR, 1.24; 95% CI, 0.68-2.24). Prostate volume was larger in men without than in those with prostate cancer (P < 0.001), and after adjustment for prostate volume, the negative association between serum IGF-I and prostate cancer risk was no longer significant (OR, 0.57; 95% CI, 0.28-1.16). In screen-positive men with elevated serum PSA, serum IGF-I is not a useful diagnostic test for prostate cancer, but it may be associated with benign prostatic hyperplasia and enlargement.
Finne
P
P
Department of Clinical Chemistry, Helsinki University Central Hospital, Finland. patrik.finne@hus.fi
Auvinen
A
A
Koistinen
H
H
Zhang
W M
WM
Määttänen
L
L
Rannikko
S
S
Tammela
T
T
Seppälä
M
M
Hakama
M
M
Stenman
U H
UH
D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D016001:Confidence Intervals; D005189:False Positive Reactions; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000032:analysis* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011467:Prostate / Q000033:anatomy & histology / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood*; D011470:Prostatic Hyperplasia / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis*; D015203:Reproducibility of Results
D014408:Biomarkers, Tumor; D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I; D017430:Prostate-Specific Antigen