There can be various causes. Some people say genes play an important factor. Yet others, for instance natural health experts, say that excessive toxins in our bodies can eventually lead to cancer. Toxins come from the foods that we eat, the unhealthy air that we breathe in and the chemicals that we expose ourselves to. It is important to be aware of what the early symptoms of cancer are, as early treatment can mean a successful recovery. Here is an article to read http://www.healthandwellnesscentral.com/Article/Early-Symptoms-Of-Cancer/21219