Bone mass and the risk of prostate cancer: The Framingham study

Purpose To examine the relation of bone mass—a potential biologic marker for cumulative exposure to androgens, insulin-like growth factors, and calcium intake—to subsequent development of prostate cancer. Methods We used radiogrammetry to measure the second metacarpal cortical area of 1012 white men with no history of prostate cancer who had undergone posteroanterior hand radiography between 1967 and 1970. Participants were followed until the end of 1999. All incident cases of prostate cancer were confirmed histologically. We examined bone mass in relation to the risk of prostate cancer using a Cox proportional hazards model. Results During follow-up, 100 men developed prostate cancer. Incidence rates per 1000 person-years were 3.8 among men in the lowest quartile of bone mass, 4.8 in the second quartile, 7.4 in the third quartile, and 6.5 in the highest quartile. Compared with men in the lowest quartile of bone mass, the multivariate-adjusted rate ratio was 1.3 (95% confidence interval [CI]: 0.7 to 2.5) for those in the second quartile, 1.9 (95% CI: 1.0 to 3.4) in the third quartile, and 1.6 (95% CI: 0.9 to 3.0) in the highest quartile (P for TREND = 0.06). Conclusion Men with high bone mass may be at an increased risk of prostate cancer. Although the biological mechanisms underlying this relation are not understood, cumulative exposure to high levels of androgen, insulin-like growth factor 1, or calcium intake may be involved.