Stephen D Hursting Michele R Forman Asad Umar Nomeli P Nunez and J Carl Barrett

More than 1 million Americans were expected to be diagnosed with cancer in 2004. This fact is especially tragic given that many cancers are preventable. The ongoing challenge to the medical, scientific, and public health communities is to formulate evidence-based decisions and implement effective and safe interventions for cancer prevention.

Randomized controlled clinical trials remain the gold standard to test cause and effect in human research and inform evidence-based medical decisions. The era of cancer prevention trials began with the seminal paper by Peto in 1981,1,2 who examined the role of b-carotene and vitamin A in cancer prevention. Since 1981, there have been numerous cancer prevention trials of nutritional interventions and phar-macologic agents. Some of these prevention trials reported clearly positive results while other trials reveal mixed results, null findings, and even unsuspected adverse effects.

A comprehensive review of all cancer prevention trials is beyond the scope of this chapter. We present here a brief review of multistage carcinogenesis and possible molecular targets for cancer prevention. We then discuss examples of randomized, controlled clinical trials that examine the effects of five different cancer prevention modalities. These case studies of human trials in cancer prevention were selected to explore the reasons why several trials did not achieve the expected cancer preventive outcomes, whereas others reached their goals. We describe the state of the art before each series of trials followed by the design, some background on the preventive agent or dietary intervention used, primary endpoints, results, and future directions. Reflections on the results are threaded with investigations of the complexities inherent to prevention trials and mechanisms underlying the adverse or null endpoints. Finally, we explore the lessons learned from the trials to identify achievable goals and the underpinnings to, and the relevant criteria for, future human research in the prevention of cancer.

10 Ways To Fight Off Cancer

10 Ways To Fight Off Cancer

Learning About 10 Ways Fight Off Cancer Can Have Amazing Benefits For Your Life The Best Tips On How To Keep This Killer At Bay Discovering that you or a loved one has cancer can be utterly terrifying. All the same, once you comprehend the causes of cancer and learn how to reverse those causes, you or your loved one may have more than a fighting chance of beating out cancer.

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