Family Legacies: Hereditary Breast Cancer in Hispanic Women

Knowledge about family history of breast, ovarian and other cancers can help individuals be proactive, prevent cancer, and increase early detection screening, when treatment is minimal.    

Cancer is usually not an inherited condition. However, approximately 10% of all cancer is hereditary, meaning it is due to a genetic mutation passed down from one’s mother or father.  Hereditary breast cancer is at least as common among Hispanic families as in any other ethnic group.(1)

Genetic Disparities in Latinas: What You Need to Know 

In all ethnic groups, a family history of breast cancer is significant. The risk of breast cancer among Hispanic women is slightly lower than non-Hispanic White women, according to the U.S. Office of Minority Health.(2) Unfortunately, the rate of death from breast cancer is higher among Hispanic women, for which there appear to be multiple reasons: lower rate of health insurance coverage and the cost of medical care not covered by insurance; decreased access to medical facilities, especially those that are culturally sensitive; and less exposure and access to information about breast cancer screening.(3)  

The two genes most commonly associated with hereditary breast cancer are BRCA1 and BRCA2. These are two genes that all humans carry, and their function in cells is to repair damaged DNA. Individuals who inherit a damaged, or mutated, BRCA gene have an increased risk of cancer, especially breast and ovarian, but also prostate and pancreatic.   

Many different BRCA1 and BRCA2 mutations have been identified in Hispanic populations. The variety of mutations identified supports the concept that the ancestral origins of Hispanics are diverse. Mutations that are common in Eastern European, Spanish, Caribbean, Mexican, and French Canadian populations have been identified in the Hispanic population.   

There are also genetic mutations that are unique among Hispanics. In a study done in Mexico City, a surprising number of women, about 21%, were found to have BRCA mutations. Of particular interest is a specific mutation in the BRCA1 gene that was found more often than other mutation and may have originated in the Mexican state of Puebla. It is estimated that this one BRCA1 mutation has been passed down in certain families for more than 1000 years.(4) BRCA mutations have also been identified that are unique to other regions, such as Columbia and Guatemala.(5)  

What Other Genes Should You Know About? 

While BRCA1 and BRCA2 are associated with the highest risk of breast cancer (up to a 70% chance), at least 50% of mutations associated with hereditary breast cancer are in genes other than BRCA1 and BRCA2. Studies of Hispanic women have identified mutations in other genes including ATM, BARD1, CHEK2, PALB2 and TP53.5 Mutations in these genes are associated with a 15-60% risk of breast cancer. One study of Hispanic women in the US identified mutations in the PALB2 and CHEK2 genes that are unique to Hispanics families and had not been reported in other populations.(2) Findings like this are important, as the results of research impact guidelines for genetic testing and screening.  

A lack of diverse populations in research will result in guidelines that do not apply to everyone.(6) In the early years of research on hereditary breast cancer, the populations studied were typically of European ancestry. The importance of including a diverse population has been recognized, and more recent studies, like the ones cited above, have included Hispanic women and other minority groups in the U.S. Increased attention has also been given to recognizing that Hispanic women are a very diverse group.  

Be Proactive With Your Breast Health! 

We should all try to gather information about the medical conditions that have affected our relatives. With regard to breast cancer risk, the following are significant in a family history:  breast cancer diagnosed younger than 50, a male relative with breast cancer, an individual diagnosed with 2 cancers, triple negative breast cancer, and a history of ovarian or pancreatic cancer.  

If you think that you might have an increased risk of breast or ovarian cancer based on your family history, ask your healthcare provider to refer you to a genetic counselor. You can review your family history and decide if you want to take the next step and have genetic testing. Insurance often covers testing. In some cases, testing may be free or cost very little.  

“Direct-to-Consumer” testing (such as 23&Me) is not recommended for something as serious as finding out about hereditary cancer risk. These tests do not offer adequate coverage of genes that should be tested. While tests like 23&Me advertise analysis of BRCA1 and BRCA2, the test actually does not cover most BRCA mutations.  

Breast cancer screening typically includes having a mammogram every year starting at age 40. For women with an increased risk, starting screening earlier, having a breast MRI, and seeing a specialist may also be recommended. Certain healthcare services are available regardless of insurance or documentation status, so please don’t delay testing or screening based on these circumstances. Also, don’t assume that what happened in your family will happen to you—early detection and treatment can mean a different outcome for you.  

Sources

1.  https://minorityhealth.hhs.gov/omh/browse.aspx?lvl=4&lvlid=61 

2.  Cancer 2019;125:2829-2836 

3.  J Natl Cancer Inst 2017 Sep 1;109(9) 

4.  Cancer Epidemiol Biomarkers Prev 2007;16(8):1615–20 

5.  Breast Cancer Research and Treatment 2021;189:533–539 

6.  JAMA Oncology March 2021;7(3):355-356