According to the American Cancer Society, men have a 50-percent chance of developing cancer during their lifetime. So you likely have a family member who has had this disease. However, only about five percent of cancers are inherited. That is why there are very specific guidelines concerning when people should consider genetic testing. These include having several first-degree relatives who have had the same kinds of cancer, family members with cancer at a young age, and cancer in your family that is linked to gene mutations.