Connection between Breast and Ovarian Cancer: Causes and Risk Factors
Breast and ovarian cancer share a considerable genetic connection, particularly among individuals carrying mutations in the BRCA1 and BRCA2 genes. These genetic mutations increase the likelihood of developing both cancers.
Research indicates that people who have undergone breast cancer treatment may face an elevated risk of developing ovarian cancer, specifically if their breast cancer is linked to BRCA1 or BRCA2 mutations. This increased risk stems from the shared genetic factors, rather than the disease itself, as research suggests those with breast cancer are approximately twice as likely to develop subsequent primary ovarian cancer.
Similarly, individuals with ovarian cancer might have a 1.6-fold increased risk of subsequent breast cancer, although this risk can vary based on the time elapsed since their initial cancer diagnosis.
Mutations in the BRCA1 and BRCA2 genes are the most significant shared risk factors between these cancers. Research estimates that around 50% of families with both ovarian and breast cancer carry BRCA1 gene mutations, while about 20% have BRCA2 mutations.
Other common risk factors for breast and ovarian cancers may include a family history of either cancer, older age, overweight or obesity, having a first child over the age of 30, never having children, not breastfeeding, and hormone therapy after menopause.
While some risk factors, such as age and family history, are unchangeable, others, such as maintaining a moderate weight, regular exercise, and reducing alcohol intake, can be managed to potentially lower the risk of both cancers.
Individuals at higher risk, including those with a history of breast or ovarian cancer, may benefit from more regular and comprehensive screenings, including mammograms, breast MRI scans, pelvic exams, transvaginal ultrasounds, and CA-125 blood tests.
For those carrying genetic mutations, preventive measures such as prophylactic surgeries may be considered to minimize the risk of cancer occurrence or spread.
While the shared risk factors and increased risks associated with BRCA1 and BRCA2 mutations are significant, there are also protective factors. Pregnancy and breastfeeding, for example, can help reduce the risk of ovarian cancer by interrupting ovulation cycles.
A 2020 observational study suggests that people diagnosed with both primary breast cancer and primary ovarian cancer have relatively favorable overall survival rates of around 90% for both the 5-year and 10-year periods. The outlook is generally more optimistic when the interval between the two cancers is longer. However, ovarian cancer following breast cancer often involves later-stage diagnosis, which can negatively affect survival.
Individuals should consult a healthcare professional if they experience symptoms of breast or ovarian cancer, especially in light of a personal or family history of these diseases. Regular screenings, preventive measures, and close monitoring are crucial for early detection and improved outcomes.
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PEOPLE CARRYING GENETIC MUTATIONS MAY BE AT INCREASED RISK OF DEVELOPING OTHER TYPES OF CANCER, SUCH AS BLADDER, BILE DUCT, COLRECTAL, ACUTE LEUKEMIA, AND MELANOMA OF THE EYE. BREAST CANCER CAN METASTASIZE TO THE OVARIES, THOUGH THIS OCCURS RELATIVELY RARELY AND IS MORE LIKELY IN ADVANCED BREAST CANCER CASES, PARTICULARLY IN THOSE THAT ARE HORMONE RECEPTOR-POSITIVE OR IN THOSE WITH BRCA MUTATIONS. THOSE WITH HIGH RISK OF OVARIAN CANCER INCLUDE INDIVIDUALS WHO HAVE BRCA1 OR BRCA2 GENE MUTATIONS, A FAMILY HISTORY OF OVARIAN, BREAST, OR COLRECTAL CANCER, LYNCH SYNDROME, ENDOMETRIOSIS, NEVER BEEN PREGNANT, HAD A LATE FIRST PREGNANCY, OR ARE AGE 40 OR OLDER.
- People carrying genetic mutations, such as BRCA1 and BRCA2, might be at increased risk of developing other types of cancer, including bladder, bile duct, colorectal, acute leukemia, and melanoma of the eye.
- Breast cancer can metastasize to the ovaries, though this occurs relatively rarely and is more likely in advanced breast cancer cases, particularly in those that are hormone receptor-positive or have BRCA mutations.
- Individuals who have BRCA1 or BRCA2 gene mutations, a family history of ovarian, breast, or colorectal cancer, Lynch syndrome, endometriosis, never been pregnant, had a late first pregnancy, or are age 40 or older may have a higher risk of developing ovarian cancer.
- Preventive measures, such as prophylactic surgeries, may be considered for those at higher risk, including those with a history of breast or ovarian cancer, to minimize the risk of cancer occurrence or spread.
- Pregnancy and breastfeeding can help reduce the risk of ovarian cancer by interrupting ovulation cycles.
- Regular screenings, preventive measures, and close monitoring are crucial for early detection and improved outcomes, especially for individuals with personal or family histories of breast or ovarian cancer.
