Genetic Testing for Cancer: Do you need it?

Genetic Testing for Cancer: Do you need it?
Genetic Testing for Cancer: Do you need it?

We all know that Angelina Jolie had a double mastectomy and had her ovaries and fallopian tubes removed after a genetic test confirmed that she had a high risk of developing ovarian or breast cancer. This was because she had a family history of breast cancer. This also led to what is known as the ‘Jolie Effect’ with people running to get genetic testing done.

However, it can be a difficult decision. While it is simple, although expensive, blood test, the results can have significant emotional and financial repercussions. For that reason, those who are thinking about getting this test can benefit from talking first with a genetic counselor.

Genetic tests are available for some types of cancer including breast, ovarian, colon, and thyroid cancers.

What is genetic testing?

Genetic testing is the use of medical tests to look for certain mutations in a person’s genes. The most commonly known is testing for changes in the BRCA1 and BRCA2 genes (which are known to increase the risk of breast cancer and some other cancers) in a woman who has a first degree relative with breast cancer.

Most cancers start because of acquired gene mutations that happen during a person’s lifetime. Sometimes these gene changes have an outside cause, such as exposure to sunlight or tobacco. But gene mutations can also be random events that sometimes happen inside a cell, without a clear cause.

Genetic testing may help:

  • Predict your risk of a particular cancer
  • Find if you have genes that may pass increased cancer risk to your children
  • Provide information to guide your health care plan. The results will help with diagnosis or management of a condition. For example, you may take steps to lower your risk. Steps may include surgery, medication, frequent screening, or lifestyle changes.

No genetic test can say whether you will develop cancer for sure. But it can tell you if you have a higher risk than most people.

Reasons to consider genetic testing for cancer

Genetic testing is a complex decision best made in consultation with your doctor and a genetic counselor.

Before undergoing genetic testing, learn about its risks and limitations. Here are some questions to help you make a decision:

  • 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 rare cancer, such as breast cancer in a male or retinoblastoma
  • A physical finding that’s 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