Understanding the relationship between different types of cancer is key to advancing our approach to prevention, diagnosis, and treatment. Breast and ovarian cancer are two of the most significant health concerns for women worldwide. When we focus on these two forms of cancer, it becomes clear that while they are distinct in nature and impact, emerging research and clinical observations have uncovered a web of genetic and biological links that bind them.
This genetic connection is often referred to as hereditary breast and ovarian cancer (HBOC) syndrome.
What is hereditary breast and ovarian cancer syndrome?
Hereditary breast and ovarian cancer (HBOC) syndrome is a genetic condition that significantly elevates the risk of breast cancer and ovarian cancer. This syndrome is primarily linked to mutations in two genes: BRCA1 and BRCA2.
“About 5-10% of breast cancers are attributed to genetic mutations, such as BRCA1 or BRCA2. One in 400 women have the BRCA mutation, making their chances of developing breast and ovarian cancer much greater,” says Dr. Candy Arentz, a breast surgeon at Houston Methodist.
Some risk factors in a patient’s medical record or family history may indicate a genetic tendency to develop ovarian cancer, including:
- A diagnosis of breast cancer at age 50 or earlier
- Bilateral breast cancers, either in you, a family member or a close relative
- A close blood relation (mother, daughter, sister, grandmother, granddaughter, niece) diagnosed with ovarian cancer
- Father, brother, uncle or grandfather with male breast cancer
- Triple-negative breast cancer diagnosed at age 60 or younger (a tumor that lacks estrogen, progesterone and HER2 receptors)
- Ashkenazi Jewish ancestry
- A previously identified BRCA mutation in the family
If any of these apply to you, you may want to talk to your doctor about cancer screening and genetic counseling.
How common is cancer with hereditary breast and ovarian cancer syndrome?
We know those affected by HBOC syndrome are at a higher risk of a cancer diagnosis. But just how much higher is that increased risk?
HBOC syndrome & breast cancer risk
According to the National Cancer Institute, about 1 in 10 women will develop breast cancer sometime during their lifetime. The risk rises for women who inherit a harmful BRCA variant. Around 6 in 10 women with a BRCA1 mutation and 4 in 10 women with a BRCA2 mutation will develop breast cancer by 70–80 years of age.
HBOC syndrome & ovarian cancer risk
The National Cancer Institute also estimates ovarian cancer risk, stating that just over 1% of women will develop the cancer sometime during their lives. Similar to how HBOC affects breast cancer risk, the risk of ovarian cancer rises for women who inherit a harmful BRCA variant. Up to 44% of women with a BRCA1 mutation and up to 17% of women with a BRCA2 mutation will develop ovarian cancer by 70–80 years of age.
How do you know if you have mutated BRCA genes?
Determining if you have gene mutations involves genetic testing, which is typically recommended based on a risk assessment. This assessment considers your personal and family medical history, looking for indicators like a history of breast or ovarian cancer, or ancestry linked to higher BRCA mutation rates. Genetic counseling is advised both before and after testing to help understand the implications of the test results. The test itself usually requires a blood or saliva sample, analyzed in a lab for BRCA mutations.
A positive result has significant implications, often leading to more rigorous cancer screenings and discussions about preventive strategies. It’s crucial to navigate this process with healthcare professionals, particularly genetic counselors, to fully understand the results and their impact on your health and family.
What are the symptoms of ovarian cancer?
“Early symptoms are subtle and mimic other benign common conditions,” says Dr. Tarrik Zaid, gynecologic oncologist at Houston Methodist Cancer Center. “But if you experience any of these for several weeks, a thorough work-up with your doctor may be needed to determine the underlying cause and to rule out the rare possibility of ovarian cancer."
Ovarian cancer symptoms to look out for:
- Shortness of breath
- Abdominal bloating or swelling
- Pelvic, abdominal or lower back pain
- Painful intercourse
- Frequent need to urinate
- Difficulty eating or getting full quickly
“Early detection improves prognosis and cure rates,” says Dr. Zaid. “Unfortunately, however, most women present at an advanced stage due to the vague symptoms.”
How is ovarian cancer treated?
Typically, treatment for ovarian cancer involves surgery to remove the tumor or tumors, and chemotherapy to kill remaining cancer cells. Additional therapies may include bevacizumab, which starves the tumor of its blood supply, and PARP inhibitors, a type of targeted therapy that may improve survival rates.
“Women diagnosed with mutations prior to the onset of cancer can undergo procedures to lower their risk,” Dr. Zaid says.
“Some women at very strong risk undergo preventive (prophylactic) surgery to help avoid future cancers,” Dr. Arentz explains. “For example, a preventive mastectomy may lower future breast cancer risk as much as 90%. Oophorectomy (surgical removal of the ovaries) may reduce ovarian cancer risk as much as 80-90% in women with a BRCA mutation.”
(Related: Why My BRCA1 Mutation Led Me to a Preventive Mastectomy)
Being in control means being aware
It’s important to remember that not every woman who carries genetic mutations associated with breast and ovarian cancer will develop the disease. The best approach is to be aware of your high risk, discuss it with your doctor, know the symptoms and have regular screenings, such as mammograms and gynecological exams.
