Geriatric oncology is a branch of medicine that is concerned with the diagnosis and treatment of cancer in the elderly, usually defined as aged 65 and older. This fairly young but increasingly important subspecialty incorporates the special needs of the elderly into the treatment of cancer. All cancer cases are preventable. Prevention offers the most cost-effective long-term strategy for the control of cancer. National policies and programmer should be implemented to raise awareness, to reduce exposure to cancer risk factors and to ensure that people are provided with the information and support they need to adopt healthy lifestyles. Worldwide, tobacco use is the single greatest avoidable risk factor for cancer mortality and kills approximately 6 million people each year, from cancer and other diseases. Tobacco smoke has more than 7000 chemicals, at least 250 are known to be harmful and more than 50 are known to cause cancer.