Besides doing things like not smoking or drink in excess, maintain a healthy weight, don't eat too much processed crap, practicing calorie restriction, try to avoid exposure to x rays, gamma rays or dangerous chemicals, it seems that most cancers aren't preventable beyond these suggestions. Only colon cancer can be effectively prevent by the use of colonoscopies. Most of them will be detected when they are advanced and start to give you symptoms.
Will this situation change in the future?
Is cancer mostly bad luck?
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