Genetic testing can help people identify risk factors for developing certain conditions, including ovarian cancer. Research has evolved significantly beyond the initial identification of the
Dr. Kristin Zorn, gynecologic oncologist, spoke with Healthline about the current state of genetic testing for ovarian cancer and what it means for people and their families.
“We used to feel that personal and family history of cancer could very reliably help us find people who had hereditary cancer syndromes.
“Over the years, especially for King syndrome and
“Now, any woman who has had ovarian cancer is eligible for genetic testing,” Zorn says.
King syndrome is also known as hereditary breast and ovarian cancer syndrome. Lynch syndrome was once known as hereditary nonpolyposis colorectal cancer.
“Genetic counselors have a college degree and then a master’s specifically in genetic counseling. They have tremendous expertise in how genes work and the ins and outs of genetic testing,” Zorn says.
There’s been a big increase in the number of companies that offer genetic testing. But as tests have become more accessible, the availability of people who can accurately interpret those tests has not gone up, Zorn explains.
She says that genetic counselors are experts one can rely on to do this interpretation.
“By definition, genetic counselors have been trained in this arena. So for some folks, that’s just the easiest way to know that they’ve got someone who this is really their bailiwick.”
“When I first started out, we tested for BRCA1 and BRCA2, and that was pretty much it. They remain the most common genes that when they’re mutated, [there’s an] increased risk for ovarian cancer.
“But there’s now a larger number of genes that can contribute to ovarian cancer risk, and many times breast cancer risk travels in parallel.
“Now, people are taking a panel test. A panel has multiple genes that are part of that syndrome. Most people are somewhere in the neighborhood of 20 genes that they include in that panel, and that continues to change,” Zorn says.
Panel sizes can include as many as 80 genes, covering every one that has been shown to increase human cancer. Zorn says there are a few factors that help determine how many genes to include in the panel.
“We want to make sure that we’re covering the cancers that have been seen in that patient and/or their family members.
“But the more genes you include in the panel, the more likely you are to get a somewhat ambiguous result called a variant of uncertain significance,” she says.
A variant of uncertain significance (VUS) has yet to be classified as a damaging mutation or a harmless one. The process of classification can take years.
“The key point is that you don’t make medical decisions based on that VUS. So, if a woman can tolerate that gray zone result, then I have no problem doing the larger panel,” Zorn says.
She notes that larger panels can also reveal risks for other types of cancers not known to be present in the family. When that situation arises, the doctor has to work with the person to decide whether steps should be taken, or not, because of the result.
Genetic testing can help people and their care teams to:
- diagnose ovarian cancer earlier
- choose treatment options for ovarian cancer
- identify changes they can make to reduce risk factors for ovarian cancer
Earlier diagnosis might be achieved through enhanced screening for people with a genetic risk for ovarian cancer.
In terms of risk factors, doctors may prescribe medication to reduce the risk.
“Birth control pills can cut the risk for endometrial and ovarian cancer by at least 50 percent. So that’s powerful medicine,” Zorn says.
In some cases, healthcare professionals may also recommend certain surgeries as a preventive measure.
In terms of treatment, Zorn offers the PARP inhibitor medications for ovarian cancer as an example of how knowledge of a mutation can inform treatment options.
Zorn noted, “we’re using PARP inhibitors for almost regardless of where the tumor starts. It’s instead based on this biomarker of carrying a BRCA mutation,” she says.
“Traditionally, people have had to go through a healthcare provider to get access to genetic testing. Now, it’s not just geneticists or genetic counselors who are specifically ordering the tests, but sometimes primary care physicians, OB-GYNs, other providers.
“There’s also direct-to-consumer genetic testing. Companies like Invitae and Color Genomics offer very high-quality [tests], essentially the same test that I could order as a healthcare professional,” Zorn says.
But Zorn notes that, even with high-quality direct-to-consumer testing, a person needs to find a healthcare professional to help make medical decisions based on those results.
The costs of tests have drastically decreased, Zorn says.
“These tests have gone from something like $4,500 for BRCA1 and 2 alone, to us being able to get almost anybody tested for $250 or less.”
She also emphasizes the importance of understanding genetic testing and its implications before going forward.
“I’ve heard some people say, ‘Oh, well, this is just another test.’ I don’t believe that at all. I believe that this is a very different kind of test that has implications not just for you, but also for your family.
“I do think people need to be aware of that going in, make an informed choice to take the test in the first place, and then have help interpreting the result and knowing what it means for themselves and for their family,” Zorn says.
People in the United States are protected from discrimination on the basis of genetic testing for some types of insurance, but not others.
“We fortunately have federal law that protects against discrimination based on the presence of a genetic mutation. That’s called GINA, the Genetic Information Nondiscrimination Act. Under the Affordable Care Act, you cannot be denied health insurance or kicked off your health insurance based on the presence of a mutation.
“The insurance company can factor in the presence of a mutation. But some companies don’t ask, and you’re not required to disclose if they don’t ask. Some companies already factor in your family history. If that family history of cancer is there, it may already be impacting your rates,” Zorn says.
However, genetic test results can be factored in for policies that cover life insurance, disability insurance, and long-term care, according to Zorn.
“There are a lot of women who had genetic testing 10, 15, 20 years ago and may have had BRCA1 and 2 [testing] only and been told that they didn’t carry a mutation. Well, our testing techniques have improved to the point that some mutations that couldn’t be detected in the past can now be detected.
“Genetic testing is not a one-time event. It’s a process,” Zorn says.
She encourages people who were tested in the past to reevaluate whether they should pursue testing using more current methods.
“We’ve had an enormous expansion in tumor testing. The tumor testing is somatic testing.
“But those are gene mutations that are only in the tumor itself. That test is not giving you an answer about the germ line,” Zorn says.
She recommends people understand whether their genetic test was a germ line or a somatic test before encouraging other family members to also receive testing.
“Someone who had tumor testing to start with may need to have a blood or a saliva sample collected to confirm what’s going on in the germ line,” Zorn says.
“I’ve tried to beat the drum about expanding access to genetic testing, because this is our chance for being proactive about cancer risk.
“We have disparities, unfortunately, for access to genetic testing. If you are from a minority population, from a rural population, if you’re male, you are much less likely to be offered genetic testing in the first place.
“So many patients are going to have to be proactive for themselves and really push this concept with their providers.
“Right now, patients may still have to be the ones who help to push for this and say, ‘Hey, I’ve got ovarian cancer. Don’t we need to think about genetic testing for me?’ and then understand what the implications are for your family members, if you test positive,” Zorn says.