Insulin-like growth factor I levels were linked to increased risk for cancer

High circulating insulin-like growth factor I concentrations were associated with a moderately increased risk for prostate cancer, according to recent findings.

Researchers from London and other sites conducted a study to examine the association between concentrations of IGF and their binding proteins and the subsequent risk for prostate cancer.

The study was conducted by researchers who have published data on circulating concentrations of sex steroids, IGF or IGF binding proteins and prostate cancer risk using blood samples collected prospectively.

Data from men with prostate cancer (n=3,700) and men without prostate cancer (n=5,200) were analyzed. The average age of participants was 61.5 years.

The greater the IGF-I level, the greater the risk for prostate cancer (OR=1.38; 95% CI, 1.19-1.60), according to the researchers.

“IGF-I and IGFBP-III were correlated (r=0.58), and although IGFBP-III concentration seemed to be associated with prostate cancer risk, this was secondary to its association with IGF-I levels,” the researchers wrote.

IGF-I concentrations were more positively linked to low-grade disease than high-grade disease.

Ann Intern Med. 2008;149:461-471.