Hereditary ovarian cancer
What is Hereditary ovarian cancer?
Gynecologic cancers include those of the ovary and uterus. About 1.3% of women will develop ovarian cancer and 2.7% will develop uterine cancer. Most cases of gynecologic cancers are sporadic and not inherited; however, approximately 5%-10% of gynecologic cancers are inherited.
Some basic facts about Hereditary ovarian cancer
Variants in two genes, BRCA1 and BRCA2, account for the majority of hereditary ovarian cancer cases in women with a strong family history or an early-onset diagnosis. These variants can increase your lifetime risk by up to 54%. Lynch syndrome is the most common inherited cause of uterine cancer.
A genetic variation in BRCA1 or BRCA2 and/or Lynch syndrome genes can increase the likelihood that a person will develop not just gynecologic cancer, but also several other types of cancer in his or her lifetime.
| Breast Cancer | Ovarian Cancer | Uterine Cancer | Colorectal Cancer | ||
| BRCA genes | BRCA1 | Up to 87% | Up to 54% | No known risk | No known risk |
| BRCA2 | Up to 84% | Up to 27% | Unknown | No known risk | |
| Lynch syndrome genes | EPCAM | Unknown | Elevated | 12%–55%+ | 75%–82% |
| MLH1 | Unknown | Up to 20% | 14%–54% | Up to 82% | |
| MSH2 | Unknown | Up to 24% | 20%–30%, up to 54% | Up to 82% | |
| MSH6 | Unknown | Up to 6%–8% | Up to 71% | ♂: up to 44; ♀: up to 20% | |
| PMS2 | Unknown | Elevated | Up to 15% | Up to 20% |
The genes listed above have also been shown to lead to slightly higher (up to 7%) risk of pancreatic cancer. For full details on genes and their associated cancer risks, including references to published scientific literature, refer to Hereditary Cancer Risks and References.
Role of genetics in diagnosis
Genetic testing may be appropriate if you have:
- ovarian, fallopian tube, or primary peritoneal cancer at any age
- uterine cancer, particularly if early-onset (before 50 years of age)
- breast cancer, particularly if early-onset (before 50 years of age)
- colorectal cancer, if early onset (before 50 years of age)
- multiple primary cancers such as uterine and colon
- a close blood relative who meets the above criteria
- three blood relatives with cancer (particularly ovarian, uterine, breast, colon, gastric, pancreatic, and/or prostate cancer)
Role of genetics in treatment
Knowing if you have an inherited risk for cancer can be a useful tool to guide prevention and risk-reduction. If you have an elevated risk of developing cancer based on your genetic test result, you can work with your healthcare provider to create a plan designed to prevent a cancer entirely, or help to identify a cancer at its earliest, most treatable stage.
In addition, genetic testing produces information that may help you and your healthcare provider:
- provide an explanation for your personal or family history of cancer
- evaluate your risk of developing future cancers
- make informed medical decisions, including treatment for an already-diagnosed cancer and/or surveillance and preventive options to help detect or prevent future cancers
- qualify you for participation in clinical trials or research studies
- identify other at-risk relatives for whom genetic testing is recommended
What can my family do with this information?
Identifying at-risk family members is one of the most important benefits of genetic testing. Screening family members for known familial genetic variants gives those who test positive the opportunity to make informed decisions on prevention strategies. For those who test negative, the results can bring peace of mind. Invitae offers a Family Variant Testing program; please inquire with your doctor.
How do I arrange for genetic testing?
Your physician will assist you in identifying and arranging for the appropriate genetic test(s). If you have specific questions or concerns about the testing, your physician may refer you to a genetic counselor to discuss further. Once you are ready to proceed with genetic testing, you will need to submit either a blood or saliva sample.
