Genetics Can Help Determine Brain Tumor Risk
Genetics can help determine a patient's risk of developing a brain tumor, as well as what treatments may work.
BY Shannon Connelly
PUBLISHED January 19, 2017
Genetic counselors can help with the complex process of assessing an individual’s risk for tumors, such as brain tumors, says Krista Qualmann, M.S., C.G.C.
Qualmann’s work as a genetic counselor at Memorial Hermann Mischer Neuroscience Institute and McGovern Medical School at The University of Texas Health Science Center at Houston includes trying to identify which patients have an inherited, genetic predisposition that could have caused them to be diagnosed with brain cancer. She also selects patients that could benefit from undergoing genetic testing.
Qualmann discussed the syndromes she is identifying in patients in her clinic, as well as how they could impact treatment, in an interview with CURE.
Can you tell us a little bit about the syndromes you are trying to identify in your patients?
We’re trying to identify patients who have an inherited, genetic, predisposition that explains why they had their brain tumor. When I’m doing this, I’m looking for patients who have some sort of red flag because the majority of our patients with brain tumors don’t have one of these syndromes. Part of my role in our clinic is to try to identify which patients would benefit the most from genetic testing.
What are some of the mutations you might see?
In the neuro-oncology world, there are a lot of different types of genetic mutations that people might be talking about. The most common genetic testing that neuro-oncologists might be talking to their patients about is the molecular genetic testing of their tumor.
The genetic testing that I’m talking to patients about is genetic testing either on a blood or saliva sample to look for a gene mutation that they were born with. Very common syndromes could include things like Li-Fraumeni syndrome, von Hippel-Lindau disease, Lynch syndrome, and a couple more.
Is this different for a pediatric patient with brain cancer?
Yes. We test for different syndromes depending on the picture of the patient in front of us. There are a lot of different hereditary cancer syndromes, so we have to narrow it down a little bit.
I narrow things down by asking a lot of questions about the patient’s past medical history and their family history. If they have characteristic patterns of cancers in their family — certain types of tumors happening together — those can lead me to be more suspicious of specific syndromes.
How do the results of genetic testing influence the therapeutic approach?
For some syndromes, knowing that a patient has a genetic predisposition syndrome tells us that maybe some therapies would be better served or should actually be avoided. For example, avoiding ionizing radiation is something we can consider, however, that is very dependent on that patient’s individual treatment plan. For patients with high-grade tumors, like glioblastomas, ionizing radiation is part of their standard of care, and so they should absolutely receive that type of treatment. For patients with lower-grade tumors, or benign tumors, if we can avoid ionizing radiation in specific syndromes, it could be beneficial for them long term.
The other thing that we can gain from identifying these genetic syndromes in patients is determining whether or not they have a higher risk for other types of cancers—other systemic diseases. For example, Li-Fraumeni syndrome is a rare syndrome, but patients are at very high risk, not only for brain tumors, but other types of cancers as well, such as early onset breast cancer in women, and sarcomas in both men and women. Those are the types of things they could be screened for if we identify that syndrome.
For Li-Fraumeni syndrome, almost every type of cancer that you can think of has been seen in at least a couple of patients. I think they have narrowed it down to four or five of the most common, but then they’re also at a very high risk for other cancers. For women specifically with Li-Fraumeni syndrome, they have a very high lifetime risk of any cancer because of their really high risk for breast cancer, which isn’t necessarily seen in men.