Check your family history
In some families, certain abnormal genes that cause cancer can be passed down from parent to child. These abnormal genes may lead to people in that family having cancer. But this is not as common as you might think. There are also other reasons why cancer may happen in many members of a family, including sharing a common environment or lifestyle.
Learn what you can about your family history of cancer. Talk to your doctor about it. Make sure to tell your doctor if your parents, children, brothers or sisters have ever had cancer. Your doctor will want to know what type of cancer these close relatives had and their age when they were diagnosed.
Your doctor can help you understand your cancer risk and talk to you about possible next steps, such as genetic testing.