Innovative Genetic Testing for Breast Cancer

Hereditary breast cancer accounts for 5 to 10 percent of all breast cancer cases. Every day, breast cancer scientists and researchers learn more about genes linked to breast cancer.

With genetic testing for breast cancer, physicians can determine the presence or absence of a breast cancer gene and if it has mutated. Measures can be taken to decrease cancer risk or treatment can be tailored to specific gene mutations.

Some breast cancer genes include:

• BRCA1 and BRCA2 genes. These are tumor suppressor genes that usually have the job of controlling cell growth and cell death. Changes to their structure may cause cancer tumors to grow. Most cases of hereditary breast cancer are linked to these genes. They also contribute to other types of cancer, especially ovarian cancer.
• PTEN gene. This breast cancer gene helps control cell growth and death. Damage to this gene creates a higher risk for both cancerous and noncancerous breast tumors. It can also lead to tumors in the thyroid, digestive tract, endometrium, and ovaries, often at a young age.
• TP53 gene. This breast cancer gene tells cells to make a protein called p53, which helps stop the growth of abnormal cells. Changes in TP53 cause an increased risk of breast cancer, leukemia, brain tumors, and childhood sarcomas. Less than 1 percent of all breast cancer is thought to be related to this gene.

When Is Genetic Testing for Breast Cancer Performed?

Genetic testing for breast cancer may not be the right diagnostic measure for some patients. Patients who are interested in genetic testing for breast cancer are encouraged to discuss testing with their physician or a genetic testing counselor. In general, the following have been identified as groups that may benefit from genetic testing for breast cancer:

• Patients who were diagnosed with breast cancer, especially triple-negative breast cancer, at a younger age
• Patients who have been diagnosed with breast cancer on two separate occasions (not first cancer recurrence)
• Patients who have been diagnosed with ovarian or pancreatic cancer
• Patients of Ashkenazi Jewish descent or Eastern European ancestry
• Patients with a familial history of breast and ovarian cancer
• Patients with a known familial history of a BRCA gene mutation
• Patients with a familial history of breast cancer at a young age

How Is Genetic Testing for Breast Cancer Performed?

Blood is drawn, saliva is taken, or a cheek swab is performed. The sample is sent to a laboratory for genetic testing. Testing is performed to look for specific breast cancer gene mutations. Testing may be specific in that it looks for a specific BRCA mutation when patients have a familial history of it. It may also focus on BRCA mutations that are common in people of Ashkenazi Jewish descent or Eastern European ancestry. If there is no familial history of gene mutations, genetic testing may look for many different gene mutations.

Results of Genetic Testing for Breast Cancer

Test results may or may not tell patients about their cancer risk. This is why it is important to go over testing results with a genetic testing counselor for clarity. Results may be:

• Positive for a breast cancer gene mutation. Steps can be taken to mitigate cancer risk for undiagnosed patients. Treatment can be tailored for diagnosed patients.
• Negative for a breast cancer gene mutation. Although it is not a guarantee, a mutation that increases risk is not found. There is always the possibility of a gene mutation that was not tested for.
• Inconclusive. The test cannot tell if there is a breast cancer gene mutation.

In some cases, results may be positive for a variant of unknown significance. What this means is a gene change or variant was found but it is unclear whether or not the change affects cancer risk.

What Are Your Risk Factors?

Talk to your health care provider today about your breast cancer risk factors and what you can do about them. Tools can be used to help estimate your risk, allowing you to set up a personalized prevention and screening plan.

Find a physician to discuss your breast cancer risk factors or recommend a genetic counselor.

To schedule an appointment with one of New Jersey’s best breast cancer specialists call 844-CANCERNJ or 844-226-2376.