Genetics and Hereditary Cancers

About 5-10 percent of all cancers are hereditary or caused by a gene that’s not working correctly. Approximately 20-30 percent of cancers are due to a combination of genetics and environment while 60 percent of cases are thought to be random or sporadic. 

Each gene in the body has its own function. A handful of genes are responsible for telling the body how to protect itself from cancer. In some families, one or more of these genes can stop working correctly, which prevents the body from getting the correct instructions for how to stop tumor/cancer development. These genes can be passed down from one generation to another. Those who inherit the faulty gene have a higher risk for developing certain cancers.

Knowing if there is a faulty gene causing cancer risk in the family can be beneficial for several reasons:

  • This information may impact management and treatment for family members who already have cancer.
  • This information will help determine if other relatives are at increased risk to develop cancer in the future. Medical management can be altered for those who are at increased risk.

Changing medical management can improve survival chances for people with a hereditary predisposition for cancer. Increased screening and surveillance, risk-reducing surgeries, chemoprevention (medication to reduce cancer risk), or lifestyle choices can lead to early cancer detection or even prevent the development of cancer.

If you’ve never had genetic counseling or testing, you can learn more about:

If you have had genetic counseling or testing, here is more information about: