Theresa L. Werner, MD
Medical Director, Clinical Trials Office, Huntsman Cancer Institute
Associate Professor, Division of Oncology, University of Utah Department of Medicine
Ovarian cancer is the second most common gynecologic malignancy in the U.S., but unfortunately it's the most deadly, or most lethal, of the gynecologic cancers that we have. And the reason for this is we don't have good screening for ovarian cancer, like we have in cervix cancer, for example with the pap test. And we don't usually get warning signs like postmenopausal bleeding like we have in endometrial cancer.
A common misconception too is that the pap test that people get for cervix cancer screens for uterine cancer, ovarian cancer, and that's not true. Because of that, most women, actually 75% of women, present with very advanced stage ovarian cancer. So, as cancer becomes more advanced, meaning it's spread to more places, it's harder to cure, for example.
Women ask me, "What's my risk of getting ovarian cancer?" An average risk is about 1.3% in U.S. women will get ovarian cancer. And that can actually increase if there are other risk factors and genetic syndromes. If you have a family member who's had ovarian cancer, a first degree relative, your risk increases from that 1% range to 5%. So, if you have a first degree relative with ovarian cancer, that is something to consider that your risk is slightly higher.
Other protective factors though for ovarian cancer, people always ask me, "What can I do to prevent ovarian cancer?" And taking oral contraceptive pills has been shown to decrease the risk of ovarian cancer. Having your ovaries and your tubes removed clearly reduces your risk of ovarian cancer as well.
One of the risk factors that we talk about a lot in ovarian cancer is genetics. So there are certain genetic syndromes that will increase your risk of developing ovarian cancer. Lynch syndrome, which also can cause an increased risk of uterine cancer, also may lead to an increased risk of ovary cancer.
But the most common syndromes that people think about in ovarian cancer is something called BRCA1 and BRCA2 syndromes. Actually, the BRCA 1 and 2 genes are important for making proteins that help repair DNA and so your body has to be able to repair DNA and not let mistakes get carried on. And, for example, in these genetic syndromes if you are missing that protein, then your body is more prone to have mistakes in the DNA, and that over time can lead to a risk of cancer. About 15 to 20% of ovarian cancers that we see are related to BRCA1 or BRCA2-like genetic syndrome.
So it's actually something that we screen all of our ovarian cancer patients that we see here to see if they have BRCA 1 or 2. It's actually a very easy test — it can either be done on blood or it can be done on saliva, and so it's a painless test and very easy to do. And we refer all of our patients, because it not only affects them because they could be at an increased risk of other kind of cancers, but it has a direct impact on their family members including their siblings and their children, both daughters and sons. So there's a 50 % chance of passing this mutation on to the children so it's actually very important for the family.
People ask me, "If I've got a BRCA mutation what's my risk of developing ovarian cancer?" In the BRCA1 mutations it's about 40% lifetime risk of developing ovarian cancer, so actually very high, If you think about an average person's risk being about 1%. And if you have a BRCA2 mutation your lifetime risk is around 15% or so for developing ovarian cancer, so still very significant. I know we're focused on ovarian cancer but these mutations can also lead to other cancers, including breast cancer, for example.
And interestingly, in the last year or so in the ovarian cancer world, we have some new targeted therapy that actually works extremely well if you have one of these BRCA mutations. This is a therapy known as PARP inhibitors and it sort of revolutionized some of the care and treatment now that we're giving ovarian cancer patients. So it's really easy testing to do and we recommend our patients speak with genetic counselors to talk about what their risk is and pursue testing if that's the right answer for them.