Human Prostate Cancer Risk Factors
Prostate cancer has the highest prevalence of any non-skin cancer in the human body, with similar likelihood of neoplastic foci found within the prostates of men around the world regardless of diet, occupation, lifestyle, or other factors. Essentially all men with circulating androgens will develop microscopic prostate cancer if they live long enough. This review is a contemporary and comprehensive literature-based analysis of the putative risk factors for human prostate cancer, and the results were presented at a multidisciplinary consensus conference held in Crystal City, Virginia in Fall 2002. The goal is to evaluate known environmental factors, mechanisms of prostatic carcinogenesis, and identify existing data gaps and future research needs. The review is divided into four sections, including (1) epidemiology (endogenous factors, family history, hormones, race, aging and oxidative stress) and exngenous factors (diet, environmental agents, occupation and other factors, including lifestyle factors); (2) animal and cell culture models for prediction of human risk (rodent models, transgenic models, mouse reconstitution models, SCID mouse, canine models, xenograft models, and cell culture models); (3) biomarkers in prostate cancer, most of which have been tested only as predictive factors for patient outcome after treatment rather than as risk factors; and (4) genotoxic and non genotoxic mechanisms for carcinogenesis. We conclude the most of the data reagarding risk relies, of necessity, on epidemiologic studies, but animal and cell culture models offer promise in confirming some improtant findings. Our understanding of biomakers of disease and risk factors is limited. An understanding of the risk factors for prostate cancer has practical importance for public health research and policy, genetic and nutritional education and chemopreventive, and prevention strategies.