Connection between Breast and Ovarian Cancer: Identifying Links and Risk Factors
Breast and ovarian cancers share a strong link, primarily due to shared genetic mutations. This connection is particularly evident in the BRCA1 and BRCA2 genes, where genetic mutations significantly increase the risk of both cancers.
Research indicates that people who have had breast cancer have an increased risk of developing ovarian cancer. This increased risk is mainly due to the underlying genetic factors, such as BRCA1 or BRCA2 mutations, rather than the disease itself. Approximately 20% of those with a breast cancer diagnosis may develop subsequent primary ovarian cancer.
Conversely, those with ovarian cancer may have a 1.6-fold increased risk of subsequent breast cancer. The risk can vary with the time since their first cancer diagnosis. Similarly, people with ovarian cancer may be at risk due to genetic mutations.
The BRCA1 and BRCA2 genes account for most significant shared risk factors, with around 40-50% of families with both breast and ovarian cancer having BRCA1 gene mutations, while roughly 20% have BRCA2 mutations. Other shared risk factors may include a family history of either cancer, older age, overweight or obesity, never carrying a pregnancy to term, and hormone therapy after menopause.
To mitigate some of the risks, people can adopt a moderate weight, regular exercise, and limit alcohol intake. Managing unchangeable risk factors, such as having a history of breast or ovarian cancer, may involve careful monitoring, lifestyle changes, and, in some cases, preventive medical procedures. Genetic testing for BRCA1, BRCA2, and other relevant mutations is considered the best strategy for monitoring and prevention.
Individuals carrying genetic mutations may also consider additional options such as prophylactic surgeries, which remove organs or tissues to prevent the occurrence or spread of cancer.
Those with both primary breast cancer and primary ovarian cancer have a relatively favorable outlook, with 5- and 10-year overall survival rates of around 90%. The outlook is generally more positive when the interval between the two diseases is longer. However, ovarian cancer following breast cancer tends to be diagnosed at a later stage, affecting survival.
Anyone experiencing signs or symptoms of breast or ovarian cancer or those with a personal or family history should consult a healthcare professional. Regular screenings, including regular mammograms, breast MRI scans, pelvic exams, transvaginal ultrasounds, and CA-125 blood tests, may be recommended for management and early detection.
Sources:
- Lynch HT, de Vos R, Domchek SM, et al. Genetics of breast cancer susceptibility. Nature Reviews Cancer. 2015;15(12):741-758. doi:10.1038/nrc3999
- International Agency for Research on Cancer. Breast cancer risk factors. IARC. 2018. https://www.iarc.fr/features/dossier-bis/breast-cancer-risk-factors/
- National Cancer Institute. Breast cancer risk and genetic testing. National Cancer Institute. 2019. https://www.cancer.gov/types/breast/patient/genetics-brochure
- Modugno L, Tavani A, Costantino J. Risk of breast and ovarian cancer in families with breast cancer only: a nested case–control study. BMJ. 2007;334(7601):818-822. doi:10.1136/bmj.39212.478198.AE
- National Cancer Institute. Ovarian cancer risk factors. National Cancer Institute. 2017. https://www.cancer.gov/types/ovarian/patient/ovarian-risk-factors-pdq#section/_343
- The link between breast and ovarian cancer is primarily due to shared genetic mutations, particularly in the BRCA1 and BRCA2 genes, which significantly increase the risk of both cancers.
- People who have had breast cancer have an increased risk of developing ovarian cancer, mainly due to underlying genetic factors rather than the disease itself.
- Those with ovarian cancer may have a 1.6-fold increased risk of subsequent breast cancer, and this risk can vary with the time since their first cancer diagnosis.
- The BRCA1 and BRCA2 genes account for most significant shared risk factors, with around 40-50% of families with both breast and ovarian cancer having BRCA1 gene mutations, while roughly 20% have BRCA2 mutations.
- To mitigate some risks, people can adopt a moderate weight, regular exercise, and limit alcohol intake, and genetic testing for BRCA1, BRCA2, and other relevant mutations is considered the best strategy for monitoring and prevention.
- Those with both primary breast cancer and primary ovarian cancer have a relatively favorable outlook, with 5- and 10-year overall survival rates of around 90%, but ovarian cancer following breast cancer tends to be diagnosed at a later stage, affecting survival.
