Your age (cancer can take decades to develop and that's why most people diagnosed with cancer are 65 or older), habits (smoking, drinking more than one alcoholic drink a day), family history (it's possible that mutations are being passed from one generation to the next), your health conditions (some chronic health conditions, such as ulcerative colitis, can markedly increase your risk of developing certain cancers) and your environment (environment around you may contain harmful chemicals that can increase your risk of cancer).
Tobacco, sunlight, ionizing radiation, some chemicals, some viruses and bacteria, some hormones, genetic predisposition, poor diet, and lack of exercise are all possible risk factors for cancer.
