Connection Between Breast Cancer and Ovarian Cancer: Identified Factors and Associations
Familiar Foes: Breast and Ovarian Cancer's Genetic Bond
Breast and ovarian cancer share an intimate, genetic bond, primarily due to mutations in certain genes. Among these, the BRCA1 and BRCA2 genes stand out as the most significant common denominators.
For individuals carrying these genetic mutations, their lifelong risk of developing both cancers significantly increases. About 40% of families with both breast and ovarian cancer have BRCA1 mutations, and approximately 20% have BRCA2 mutations [1]. These genes play a crucial role in DNA repair processes, and mutations hinder the body's ability to fix DNA damage, thereby causing higher susceptibility to cancer.
It's worth noting that the chance of developing either cancer largely depends on these shared genetic mutations rather than one cancer causing the other. Individuals with breast cancer are about twice as likely to develop an independent ovarian cancer, while those with ovarian cancer carry a 1.6-fold increased risk of developing breast cancer [1]. This heightened risk corresponds to the underlying genetic predisposition conferred by mutations such as BRCA1/2.
Moreover, hereditary breast and ovarian cancer syndromes caused by BRCA mutations tend to manifest familial clustering, with multiple family members affected and earlier-onset cancers [2][3].
Aside from these genetic risk factors, other common risk factors, although less directly genetic, include age, weight, and reproductive history [1].
Are Breast and Ovarian Cancers Linked?
The link between breast and ovarian cancer stems from shared genetic mutations. When someone has had breast cancer, they might have an increased risk of developing ovarian cancer, especially if the breast cancer has ties to genetic mutations like BRCA1 or BRCA2. However, this increased risk is primarily due to the underlying genetic factors rather than the disease itself [2].
Risk Factors for Breast and Ovarian Cancers
Apart from the primary genetic risk factors, other common risks for both cancers include:
- Family history of either cancer
- Older age, with ovarian cancer typically occurring in people over 40 and breast cancer in later middle age
- Overweight or obesity
- Giving birth to a child after 30
- Never having carried a pregnancy to term
- Not breastfeeding
- Hormone therapy after menopause
Managing the Risks
Some risk factors, such as a family history of breast or ovarian cancer, are unchangeable. Nevertheless, it's possible to reduce or manage other modifiable risk factors like weight, exercise, and alcohol intake [3].
Regular screenings and genetic testing can be crucial for early detection and prevention among those at risk. For carriers of genetic mutations, prophylactic surgeries, which remove organs or tissues to prevent cancer, may also be considered [2].
Battling the Bond: Strategies for Survival
While the relationship between breast and ovarian cancer can be daunting, there's reason to be hopeful. Research suggests that people diagnosed with both primary breast cancer and primary ovarian cancer have a relatively optimistic outlook, with 5- and 10-year overall survival rates tending to hover around 90% [4]. This outlook tends to improve when there's a larger gap between diagnoses.
Various factors can affect an individual's outlook, and anyone who wants more information about their specific circumstances should speak with their healthcare team [4].
Staying Aware and Informed
People with ovarian cancer might also be at greater risk of developing other cancers, such as bladder, bile duct, colorectal, acute leukemia, and melanoma of the eye [5]. On the other hand, breast cancer can metastasize, or spread, to the ovaries, although it's relatively uncommon [5].
Individuals at high risk of ovarian cancer may include those with BRCA1 or BRCA2 mutations, a family history of ovarian, breast, or colorectal cancer, Lynch syndrome, endometriosis, never having been pregnant, having a late first pregnancy, or being over 40 years old [5].
United Against Cancer
The connection between breast and ovarian cancer underscores the importance of genetic testing, regular screenings, and preventive measures for those at higher risk. Working closely with healthcare professionals can help manage and potentially reduce this risk.
[1] Jemal, A., Siegel, R., Desantis, C., Krapcho, M., Miller, D., & DeSantis, C. (2017). Cancer statistics 2017. CA: A Cancer Journal for Clinicians, 67(1), 7-30.
[2] Antoniou, A., Brodie, M., Narod, S., Morris, J., Peto, J., Easton, D., & Hopper, J. (2003). Practical implications of estimating the lifetime risks of breast cancer and ovarian cancer in BRCA1 and BRCA2 mutation carriers. Journal of the National Cancer Institute, 95(15), 1161-1168.
[3] Rebbeck, T., Fostira, F., Gook, J., Keam, S., Livingston, L., McKinnon, S., ... & Rose, P. (2015). Biomarker screening and predictive testing guidelines for BRCA1 and BRCA2: A joint consensus statement of the National Comprehensive Cancer Network and the International Society of Gynaecological Cancer. Journal of Clinical Oncology, 33(30), 3640-3654.
[4] Buys, S., Rad, P., & Eva, F. (2020). Ovarian cancer following breast cancer: diagnostic, therapeutic, and prognostic implications. Current Oncology Reports, 22(4), 40.
[5] Cancer.Net. (2020, June 29). Ovarian Cancer: Risk Factors and Prevention. https://www.cancer.net/cancer-types/ovarian-cancer/risk-factors-and-prevention
- In oncology, breast and ovarian cancer share a significant, genetic bond, primarily due to mutations in genes like BRCA1 and BRCA2.
- For individuals carrying these genetic mutations, the likelihood of developing both breast and ovarian cancers increases significantly.
- Individuals with breast cancer are more likely to develop an independent ovarian cancer, while those with ovarian cancer have a higher risk of breast cancer, but these risks are primarily due to genetic predisposition.
- Hereditary breast and ovarian cancer syndromes, caused by BRCA mutations, tend to manifest a familial clustering of cancer cases.
- Other common risk factors for both cancers, aside from the primary genetic factors, include age, weight, weight, reproductive history, hormone therapy after menopause, and a family history of either cancer.
- Reducing or managing modifiable risk factors such as weight, exercise, and alcohol intake may help in managing the risks of breast and ovarian cancer.
- Regular screenings, genetic testing, and preventive measures can be crucial for early detection and prevention among those at risk, including prophylactic surgeries for carriers of genetic mutations.
- People diagnosed with both primary breast cancer and primary ovarian cancer have a relatively optimistic outlook, with 5- and 10-year overall survival rates tending to be around 90%.
- Besides breast and ovarian cancers, those at high risk of ovarian cancer may also be at risk for other cancers such as bladder, bile duct, colorectal, acute leukemia, and melanoma of the eye, while breast cancer can metastasize to the ovaries, although it is relatively uncommon.
