Hereditary Cancer and Genetic Testing

Cancer risk associated with inherited BRCA1 mutations

If you have tested positive for a BRCA1 mutation, we recommend that you consult with a genetics expert who can assess your personal and family history of cancer, and help you determine the best risk management plan.

Research on lifetime cancer risk for people with BRCA1 mutations has varied. The following risks are estimates based on review of different large studies. The average age of a cancer diagnosis is younger in people with a BRCA1 mutation than people who do not have a mutation. 


Risks in women

  • Breast cancer: The lifetime risk for a women with a BRCA1 mutation is about 65 percent compared to 12.5 percent for an average risk woman. 
  • Ovarian cancer: The lifetime risk for a women with a BRCA1 mutation is about 40 percent compared with 1.3 percent for an average risk woman.
  • Second breast cancer in women who have alread been diagnosed with breast cancer: The lifetime risk is about 40 percent.
  • Uterine cancer: There is a slightly increased risk for a rare form of aggressive uterine cancer, the estimated risk to age 70 is less than 5 percent


Risks in men

  • Prostate cancer: The lifetime risk for a man with a BRCA1 mutation is about 16 percent compared to 12 percent for an average risk man. Prostate cancers in men with inherited BRCA1 mutations may be more aggressive than in men without an inherited mutation. 
  • Male breast cancer: The lifetime risk for a man with a BRCA1 mutation is about 2 percent.

Risks in both men and women

  • Pancreatic cancer: The lifetime risk for a person with a BRCA1 mutation is about 5 percent compared to 1 percent for an average risk person. 
  • Research on how mutations in the BRCA1 gene affect cancer risk is ongoing. Some research suggests that BRCA1 mutations may increase risk for melanoma. However, because these studies are not conclusive, genetics experts often look at a person’s family history of cancer to help people with BRCA1 mutations understand their risk for additional cancers.

Graph of lifetime breast cancer risk in women with a <abbr
                data-toggle='tooltip'
                class='glossary-tip tt-brca1'
                title='<p>BRCA1 is a gene found on chromosome 17. Mutations in BRCA1 increase the risk for cancers including breast, ovarian, pancreatic, prostate,&nbsp;melanoma and possibly other cancers. BRCA1&nbsp;mutations are among the genes associated with Hereditary Breast and Ovarian Cancer Syndrome, also known as HBOC.&nbsp;</p>
'
            >BRCA1</abbr> mutation       Graph of lifetime ovarian cancer risk in women with a <abbr
                data-toggle='tooltip'
                class='glossary-tip tt-brca1'
                title='<p>BRCA1 is a gene found on chromosome 17. Mutations in BRCA1 increase the risk for cancers including breast, ovarian, pancreatic, prostate,&nbsp;melanoma and possibly other cancers. BRCA1&nbsp;mutations are among the genes associated with Hereditary Breast and Ovarian Cancer Syndrome, also known as HBOC.&nbsp;</p>
'
            >BRCA1</abbr> mutation

Graph of lifetime pancreatic cancer risk in people with a <abbr
                data-toggle='tooltip'
                class='glossary-tip tt-brca1'
                title='<p>BRCA1 is a gene found on chromosome 17. Mutations in BRCA1 increase the risk for cancers including breast, ovarian, pancreatic, prostate,&nbsp;melanoma and possibly other cancers. BRCA1&nbsp;mutations are among the genes associated with Hereditary Breast and Ovarian Cancer Syndrome, also known as HBOC.&nbsp;</p>
'
            >BRCA1</abbr> mutation       Graph of lifetime prostate cancer risk in men with a <abbr
                data-toggle='tooltip'
                class='glossary-tip tt-brca1'
                title='<p>BRCA1 is a gene found on chromosome 17. Mutations in BRCA1 increase the risk for cancers including breast, ovarian, pancreatic, prostate,&nbsp;melanoma and possibly other cancers. BRCA1&nbsp;mutations are among the genes associated with Hereditary Breast and Ovarian Cancer Syndrome, also known as HBOC.&nbsp;</p>
'
            >BRCA1</abbr> mutation

 

clinical-trials

The following are studies are looking at cancer risks in people with a BRCA1 mutation.