- Genetic counseling and testing may be recommended for people who have had certain cancers or certain patterns of cancer in their family. If you have any of the following, you might consider genetic testing:
- Several first-degree relatives (mother, father, sisters, brothers, children) with cancer
- Many relatives on one side of the family who have had the same type of cancer
- A cluster of cancers in your family that are known to be linked to a single gene mutation ( such as breast, ovarian, and pancreatic cancers in your family).
- A family member with more than 1 type of cancer
- Family members who had cancer at a younger age than normal for that type of cancer
- Close relatives with cancers that are linked to rare hereditary cancer syndromes
- A family member with a rare cancer, such as breast cancer in a male or retinoblastoma
- Ethnicity (for example, Jewish ancestry is linked to ovarian and breast cancers)
- A physical finding that is linked to an inherited cancer (such as having many colon polyps)
- A known genetic mutation in one or more family members who have already had genetic testing
- If you are concerned about a pattern of cancer in your family, cancer you’ve had in the past, or other cancer risk factors, you may want to talk to a health care provider about whether genetic counseling and testing might be a good option for you.
- You need to know your family history and what kinds of tests are available. For some types of cancer, no known mutations have been linked to an increased risk. Other cancer types may have known mutations, but there is no way to test for them yet.
-Family Cancer Syndromes gives you more information on the types of cancers that may be linked to inherited genes.
- Cancer is a common disease, so it is no surprise that many families have at least a few members who have had cancer.
- Sometimes, certain types of cancer seem to run in some families. In some cases, this might be because family members share certain behaviors or exposures that increase cancer risk, such as such as smoking. Cancer risk might also be affected by other factors, like obesity, that tend to run in some families.
- But in some cases, the cancer is caused by an abnormal gene that is being passed along from generation to generation. Although this is often referred to as inherited cancer, what is inherited is the abnormal gene that can lead to cancer, not the cancer itself. Only about 5% to 10% of all cancers result directly from gene defects (called mutations) inherited from a parent. This information is about those cancers.