The brain/mind and the body's chemicals work with one another. Hormones could be affected, etc. That's why so many medications come with such long warning labels. The meds treat the level of hormones, etc in the brain to help someone with emotional issues. If your bodies chemicals (hormones, etc) are not in balance, the body organs don't operate as efficiently which leads to further problems. Well, I don't know...because I need details to see where you are going with your question. But any dysfunctional or unnatural (environmental, behavioral, nutritional, etc.) things that your body goes through can be cancerous because your body will produce more mutations. I think stress can be classified as a symptom of a malfunctioning mind some of the time so it may be able to contribute to cancer. I guess I could give you a better answer if your question was a bit more clarified. The normal functioning of the body depends almost entirely on a normal functioning mind,you need to be familiar with the anatomy and physiology to believe this.

In case of any doubt regarding this staement plese refer to a textbook desribing the normal functioning of a human cell.