Insulin-like growth factors and risk of kidney cancer in men

Abstract

Background: Insulin-like growth factor-I (IGF-I) has been shown to increase kidney growth, glomerular filtration rate, and renal function.

Methods: In the prospective Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) study of 29 133 Finnish male smokers aged 50-69 years, serum concentrations of IGF were measured in samples collected in 1985-1988. A total of 100 men with kidney cancer diagnosed > or =5 years after blood collection through 1997 were compared with a subcohort of 400 men; logistic regression models were used to estimate the risk of developing kidney cancer.

Results: Men with IGF-I levels >113 ng ml(-1) were 59% less likely to develop kidney cancer than men with levels < or =113 ng ml(-1) (odds ratio=0.41; 95% confidence interval=0.23-0.75). The IGF binding protein-3 (IGFBP-3) levels did not alter the association. No association was observed between IGFBP-3, or molar ratio of IGF-I/IGFBP-3, and kidney cancer.

Conclusions: Low serum IGF-I levels in this cohort of older middle-aged male smokers are associated with increased kidney cancer risk, independent of IGFBP-3.

Figure 1

Multivariable-adjusted odds ratios for quartiles of IGF-I, IGFBP-3, and IGF-I/IGFBP-3 molar ratio. Adjusted for age, weight, height, cigarettes per day, and hypertension. IGF-I and IGFBP-3 were simultaneously adjusted for in their respective models. P-values for overall effect.