BRCA Carriers are 80% More Likely to Develop Breast Cancer: Do You Carry It?

Over 99% of human DNA is identical. However, a small part of your DNA makes you the unique person that you are. You know that your hair and eye colors are genetic, but did you know that our DNA can tell us if we may be at-risk of certain cancers and diseases?

For Breast Cancer Awareness Month, we are highlighting one such gene variant that increases a person’s risk of breast, ovarian, and prostate cancer, called BRCA 1 and 2.

What Angelina Jolie Taught Us About Hereditary Cancers

In 2013, actress and humanitarian Angelina Jolie wrote in The New York Times about her decision to have a preventive bilateral mastectomy. Angelina Jolie had two strikes against her related to her risk of breast and ovarian cancer: She had a mutation in the BRCA1 gene and she lost her mother, grandmother, and aunt to cancer. These raised her risk of developing breast cancer to over 80%. Angelina’s case increased public awareness of breast cancer and inquiries about BRCA gene testing skyrocketed.

How did Angelina Jolie find out she was a BRCA1 carrier?

It was through a simple blood panel that’s widely available and may be covered by your insurance. Dr. Megan Grunander is a General Surgeon who orders blood panels regularly for high-risk patients. She says, “Genetic screenings are one of the great things we can do to identify cancer risks, in addition to screening mammograms after age 40. We want to conduct blood panel screenings for patients who have:

• Two family members who’ve had breast cancer (one premenopausal),
• One family member who has had ovarian cancer, or
• Three family members who have had breast cancer at any age.”

BRCA Carriers VS the General Population

Eighty percent of breast cancer patients do not have a family history of it. Breast cancer is not always hereditary. Altered gene carriers, such as those carrying BRCA 1 or 2, do not always develop breast, ovarian, or prostate cancer, but they do have a higher risk than the general population.

General population

During their lifetime, women have a:

• 15% risk of breast cancer
• 2% risk of ovarian cancer

BRCA1 carriers

Women with an altered BRCA1 gene have a:

• 60–87% risk of breast cancer
• 40–60% risk of ovarian cancer

Men with an altered BRCA1 gene have a 0.1–1% risk of breast cancer.

BRCA2 carrier

Women with an altered BRCA2 gene have a:

• 45–85% risk of breast cancer
• 10–30% risk of ovarian cancer

Men with an altered BRCA2 gene have a 5–10% risk of breast cancer, and up to 25% risk of prostate cancer.

Breast, ovarian, or prostate cancer runs in my family. What happens now?

If you have a Primary Care Provider (PCP), make sure they know about who has had cancer in your family and the age they found it. This should be recorded in your medical chart for future health practitioners to see as well.

Your PCP or OB/GYN may order a genetic blood panel if he/she identifies you as a high-risk patient. However, if you’ve never had this discussion with them, initiate it at your next exam to see if you’re a candidate for a hereditary cancer screening.

After the test, if you are not a carrier…

If the genetic test yields a negative result for the BRCA gene, your risk of developing breast cancer is the same as the general population. It also means any children you have or may have will not inherit this altered gene. You are a non-carrier for life; BRCA cannot develop later down the road.

If you have an altered gene…

If the test shows you have inherited the altered gene found in your family (a positive result), your chance of developing breast cancer, and possibly other cancers, is much higher than the general population.

Your healthcare team will discuss what options are available to manage your risk, including:

• More frequent cancer screenings beginning earlier in life
• Risk-reducing surgery such as preventative mastectomy or hysterectomy

It's difficult to learn that you carry a gene variant. You’re likely to have many questions such as how to tell your family and whether to take risk-reducing measures. Your health team will support and educate you you during this time to reach a decision you both feel comfortable with.

For more information about hereditary cancer screenings, listen to Dr. Megan Grunander discuss hereditary cancer screenings on ABC4 Utah here.