Adapted from an original article published in Science:
Plasma Insulin-Like Growth Factor-I and Prostate Cancer Risk
June M. Chan, * Meir J. Stampfer, Edward Giovannucci, Peter
H. Gann, Jing Ma, Peter Wilkinson, Charles H. Hennekens,
Michael Pollak (Harvard School of Public Health,
Northwestern University Medical School, and McGill
"Can a simple blood test predict a man's risk of later developing prostate cancer?"
In this preliminary, but potentially important publication, medical researchers found that measurement of a plasma protein --- Insulin-like Growth Factor-I (IGF-I) --- can do just that. Men who were entered into the Harvard Physician's Health Study in 1982 had plasma samples stored, then the men were followed for 10 years. None of the men had prostate cancer in 1982, but over the next 10 years, 152 men with stored plasma samples subsequently developed prostate cancer.
Those men who who had the highest quartile IGF-I levels in 1982, developed prostate cancer at a relative risk of 4.3 times that seen in men who were in the lowest 1982 quartile. The authors found that this association was independent of baseline PSA levels. IGF-I is known to be a powerful mitogen (inducer of cell division) in prostate epithelial cells; thus the theoretical basis for this finding seems to be quite sound.
Further discussion of this article is available free of charge via the Science website (http://www.sciencemag.org). The complete article is available online to Science suscribers.