Asking if ovarian cancer is genetic is a bit of a loaded question.
Technically, all cancer is genetic. That’s because the disease develops when a single cell acquires a genetic change that spurs it to grow out of control. Yet while all cancers are caused by damage to the genes, only some are caused by damaged genetic material that’s inherited, meaning it’s passed down in families. Instead, most cancers develop from gene damage that’s caused by environmental or lifestyle factors.
Still, ovarian cancers have a greater hereditary susceptibility, or a cause linked to inherited genetic damage, than most cancers. Rachel Reagle, MS, CGC, a licensed certified genetic counselor at City of Hope®, puts the range at 10 percent to 25 percent—compared to most cancers’ range of 5 percent to 10 percent.
For that reason, genetic testing is especially important when it comes to detecting and preventing cancer of the ovaries.
In this article, we’ll explore:
If you’ve been diagnosed with cancer and are interested in a second opinion on your diagnosis and treatment plan, call us or chat online with a member of our team.
Is ovarian cancer genetic?
Although up to 25 percent of ovarian cancers are linked to an inherited genetic change, or mutation, the majority occur due to other factors. Some of these cancers develop because of an environmental exposure or lifestyle factors. Others begin to grow completely by chance.
Other cancers develop in several members of the same family due to a shared but unknown factor that may be traced to lifestyle or the environment but can’t be linked to a common genetic mutation.
“I don’t know if we have an answer to the question of why ovarian cancer’s percentage range is higher than others when it comes to a genetic link, but one of the things that comes to mind is that ovarian cancer, overall, is just a rare type of cancer to get,” Reagle says, noting the average risk for breast cancer is about 1 in 8, or about 13 percent. The average risk of developing ovarian cancer is about 2 percent.
BRCA and other genes
Most ovarian cancers that are hereditary—between 65 percent to 85 percent of them—are associated with a BRCA1 or BRCA2 gene mutation. “Those are still the main common cause of hereditary ovarian and breast cancer,” Reagle says.
But changes to the BRCA genes aren’t the only gene mutations tied to an increased risk for developing ovarian cancer. Others include mutations in the five genes (MLH1, MSH2, MSH6, PMS2 and EPCAM) present in people with Lynch syndrome, a rare genetic condition that increases the risk for developing certain types of cancer, especially colorectal and endometrial.
Mutations in the tumor suppressor gene, TP53, in Li-Fraumeni syndrome —another rare genetic condition linked to an increased risk for multiple types of cancer—and other genes, including CHEK2, RAD51, BRIP1 and PALB2, are also associated with a higher risk for developing ovarian cancer.
Is an ovarian cancer screening test available?
Unfortunately, there’s no good screening test available for ovarian cancer, Reagle says. That’s why genetic testing is recommended for women with a personal or family history of the disease.
“It’s important to know your history and seek genetic testing if indicated because ovarian cancer is hereditary a higher percentage of the time,” she says. “And it’s important to get genetic testing because, if we know you have a higher risk to begin with, we might decide a preventive measure, like ovary or fallopian tube removal, is right for you.”
Genetic testing for hereditary ovarian cancer is recommended for women who have:
- A strong family history of breast and ovarian cancer
- A moderate family history of breast and ovarian cancer and are of Ashkenazi or Eastern European Jewish descent
- A personal history of breast cancer and meet certain other criteria, including those related to age at diagnosis
- A personal history of ovarian, fallopian tube or primary peritoneal cancer
- A known mutation in the BRCA genes in someone in your family
Ovarian cancer prevention
In addition to genetic risks, other factors are associated with a lower chance for developing ovarian cancer including:
- A history of a tubal ligation (having your tubes tied), the removal of both the ovaries or fallopian tubes, or a hysterectomy (having your uterus and, sometimes, your cervix removed)
- Breastfeeding
- Giving birth
- Using estrogen- and progesterone-containing birth control pills for five or more years
Still, you should always talk to your doctor about your individual risk for ovarian cancer and the best ways to reduce it.
“As genetic counselors, we often get questioned a lot about risk factors, but we always encourage people to have conversations with their doctor,” Reagle says. “Not all preventions are recommended for everyone. It should definitely be specific to each individual.”
If you’ve been diagnosed with cancer and are interested in a second opinion on your diagnosis and treatment plan, call us or chat online with a member of our team.
