Young Black Women With Breast Cancer More Likely to Have BRCA Mutation

Young black women diagnosed with breast cancer are about twice as likely to have BRCA genetic mutations than non-Hispanic white women of similar age with breast cancer. The finding, from the largest U.S.-based study of its kind, was reported in the journal Cancer.

Background and Goals

Studies show that about 5 percent of women of all ages who are diagnosed with breast cancer have a BRCA1 or BRCA2 mutation. However, those studies have been conducted mostly in non-Hispanic white women.

Most breast cancers associated with a BRCA1 gene mutation appear before age 50 and often are triple-negative, meaning they do not need specific hormones to grow as other subtypes do.

Non-Hispanic white women are slightly more likely to be diagnosed by age 50 than black women. But young black women are more likely to have triple-negative breast cancer and a significantly lower 10-year survival rate than their white peers.

Black women are also less likely to be referred for and to have BRCA genetic testing than white women are, according to previous research. This may be due to lack of access or awareness, or other factors.

In this study, the researchers wanted to find out how common BRCA mutations were in a broad sample of young black women diagnosed with breast cancer. They also looked at the disease characteristics for those with or without a BRCA mutation.

Design
Using information from the Florida Cancer Registry, researchers recruited black women who were diagnosed with invasive breast cancer at age 50 or younger. All were Florida residents and diagnosed from 2009 to 2012.

The women reported their race as black, which included African-American, Afro-Caribbean and other mixed-race descents.

Women consented to share their medical records with the researchers. They also completed a questionnaire and spoke by telephone with a certified genetic counselor.

Each participant provided a saliva sample by mail. They received free testing for BRCA mutations in DNA extracted from that sample.

Results

Of the 396 women included in the study, BRCA mutations were found in

• 22 percent of those diagnosed at age 35 or younger
• 13 percent of those diagnosed at ages 36 to 40
• 11 percent of those diagnosed at ages 41 to 45
• 8 percent of those diagnosed at ages 46 to 50

The older the age at diagnosis, the less likely a person was to have a BRCA1 mutation, while 4.3 percent of women in all age categories carried a BRCA2 mutation.

Compared with women in the study who did not have a BRCA mutation, BRCA carriers were more likely to have

• triple-negative breast cancer
• a family history of breast or ovarian cancer
• a diagnosis before age 45

Overall, 12.4 percent of women in the study had a BRCA1 or BRCA2 mutation.

Among the BRCA carriers, 41 percent had no family history of breast or ovarian cancer. The researchers believe this shows that family history alone may not be reliable for predicting BRCA risk. They concluded it may be appropriate to recommend BRCA testing for all black women with invasive breast cancer diagnosed at age 50 or younger.

Limitations

The study only included young black women from Florida, so findings might differ in other states.

What This Means For You

You may be wondering if you should have genetic testing for BRCA mutations. If you are black and were diagnosed with breast cancer at age 50 or younger, this study suggests that genetic counseling and testing may be important for you and your family.

Others with higher BRCA risk include people of Ashkenazi (Eastern or Central European) Jewish descent, or those with several relatives with breast cancer, a male relative with breast cancer, or any relative with ovarian cancer.

Knowing you have a BRCA gene mutation can help you get the best treatment and be monitored appropriately in the future.

If you have a BRCA mutation, your biological children, female and male, are at higher risk. So are your close blood relatives, such as sisters, brothers and parents. Knowing their risk can help them get proper cancer screenings, often earlier than usual.

Pal, T, Bonner, D, Cragun, D, et al. A High Frequency of BRCA Mutations in Young Black Women With Breast Cancer Residing in Florida. Cancer 2015; doi: 10.1002/cncr.29645

This article was supported by the Grant or Cooperative Agreement Number 1 U58 DP005403, funded by the Centers for Disease Control and Prevention. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the Centers for Disease Control and Prevention or the Department of Health and Human Services.