Digital Editor, Inspire
Nisha Isaac, M.S., is a certified genetic counselor at the University of Maryland’s St. Joseph Medical Center who focuses on cancer patients. I spoke with her about the role of genetic counselors in understanding cancer risks and the counseling process.
Briefly, what is genetic counseling?
The goal of cancer genetic counseling is to educate patients about genetic testing options and the implications of testing. The majority of cancers are not inherited. However, if someone has cancer or a family history of cancer that is caused by an inherited problem, then they might be at increased risk for developing the same or other cancers. These individuals and families are considered high risk and need to be managed and treated differently. Management and treatment options for individuals at high risk include increased screening, preventative medications and surgical options. Our goal with genetic testing is to detect cancer at an early stage or even prevent it in some cases.
Who should get genetic counseling and when?
Individuals who have been diagnosed under the age of 50 years, have a family history of different cancers (breast, ovarian, prostate, pancreatic, colon etc.) or who are from high risk populations such as the Ashkenazi Jewish population might be candidates for genetic testing. Testing can be offered to individuals who have cancer or to unaffected individuals, although individuals with cancer are the more ideal candidates for testing. Fifty percent of my patient population is affected, meaning they are currently diagnosed with cancer or have a history of a cancer diagnosis. Testing criteria has been established by the National Comprehensive Cancer Network. Insurance companies base their own criteria on these guidelines.
Genetic counseling provides the patient with a detailed evaluation that looks at the bigger picture. This results in the patient being offered the appropriate gene tests and allows for a more accurate interpretation of the genetic test results.
What happens in a counseling session?
Prior to the genetic counseling session, patients are asked to fill out a family history questionnaire that collects personal and family history information and asks about possible concerns and questions. Sessions are personalized to fit the needs of the patient. The time for each session ranges depending on the size of the family history and how many questions the patient might have. Other issues such as dementia or current health might also impact the length and content of the session.
Genetic counseling also has a psychosocial component to it. A newly diagnosed cancer patient who is 32 years old with young kids has different needs and concerns than a 68-year-old. They are both coming to me to discuss genetic testing but how they feel is generally very different so they need to be treated differently. We discuss not only genetic risk factors but also environmental risk factors such as lifestyle. I also explore whether the patient needs any additional support such as a nutritionist or social worker.
Is there a measurable difference in how genetic counseling can affect your treatment options?
The short answer to this question is yes. Let me tell you about one of my patients. I had a 29-year-old patient with colon cancer. Her father died at 41 years from metastatic colon cancer. I offered her genetic testing and she had a hereditary colon cancer syndrome. Several years later, her children were having gastrointestinal problems and came to me for testing. Both her daughters tested positive for the same gene problem. The elder, 12 years old, has polyps all through her colon and is having her colon removed. She will live with a colostomy and have a different quality of life because she will need to be careful about her diet. But, if she did not have the genetic testing and did not know about her diagnosis, she would have had an almost 100% chance of developing colon cancer. Thankfully, she’s a well-adjusted young girl and her life will be saved. She won’t die like her maternal grandfather did from metastatic colon cancer.
That’s an extreme example so to give you another, I have counseled several Jewish families with a family history of pancreatic cancer. If they test positive for certain gene problems we send them to a pancreatic screening specialist. Last year, the specialist found two early stage pancreatic cancer cases and saved their lives.
Once you begin to explore your genome, what is the extent to which immediate and even extended family become involved?
Once the patient has been tested we have a better idea about what might we might be able to offer their family. Genetic testing offers patients information about health care risks not only for themselves but also for their family. When you can pinpoint the cause of disease, it ripples outwards to affect the wider family. Hopefully this information can be used to catch the disease early or to stop that pattern of disease through preventative options.
Do patients have to know about statistics, probability, and genetics to understand testing and counseling?
It’s my job to make medical information understandable to everybody. I try to keep the information simple. I do talk about probabilities, risk factors, benefits, and limits of genetic testing and treatment and management options. In our sessions, I use slides and summarize the information at the end, making sure to touch base with patients to see if there are any questions. I also provide them with a summary handout in case they want to review what was discussed.
How do you feel about genetic tests from private companies like 23andMe?
In private companies, the sequencing and analysis technology is different from what we use*, which is a test validated based on a set of standards. Also, test results might be different between companies depending on what markers they use. In addition, the risk assessment might be more appropriate for some populations than others. The limits of testing by companies such as 23andMe are complex and usually found buried in the small print.
Can you seek genetic counseling after you’ve gotten test results from a private company?
Yes, you can. I mostly see families who have a reason to seek genetic counseling outside curiosity. But the National Society of Genetic Counselors provides a resource to find counselors in different geographical areas to talk with about these kinds of results.
How do you help patients manage the stress of knowing or not knowing their genetic risk of cancer?
Whether the test results are considered “good” or “bad” depends on the person and their situation. Some patients really want a positive result because it gives them an explanation with can result in relief. Others are happy to get a negative result and not have to worry about passing on increased cancer risks to their children, so they can also feel relief.
I try to help patients understand that If they have genes that put them at increased risk for cancer, then they’ve always had them – that hasn’t changed. But once they know about the cancer risks, they can be proactive in how they use the information. The information can be used to prevent a second cancer in the affected patient or for earlier detection or prevention of cancer in the patient or their close and extended family members.
Do you ever not recommend genetic testing?
Not often, but sometimes – if a patient isn’t interested in early detection through screening or preventative options then there’s no point in doing the testing. I also don’t recommend testing if patients have a low likelihood of finding an answer, even if really want to do it and are willing to pay for the testing out of pocket. That being said, I will not deny patients the option of testing if they want to pay for it out of pocket.
What does the future of genetic testing and counseling look like to you?
As I look forward, I see the potential for population based whole genome sequencing and whole exome** sequencing that will let people get that personalized health care report card they are looking for. We’re just not there yet. With the expansion of genetic testing options, we’ll need genetic counselors who can analyze a broader spectrum of genetic diseases so that they can provide services more effectively.
*Private companies examine single nucleotide polymorphisms – errors or variations at singular spots throughout the genome – to generate a report. Genetics counselors typically work with labs that do next-generation sequencing, which maps out multiple pieces of DNA at once, and deletion/duplication analysis to look for those types of changes in specific genes.
**Whole exome sequencing targets the parts of the genome that make proteins.
If you have had experience with genetic counseling or genetic testing, please share them in the comments!
This content is for general informational purposes only and does not necessarily reflect the views and opinions of any organization. The content should not be used as a substitute for professional medical advice, diagnoses, or treatment. Please consult your healthcare provider about any questions you may have regarding a medical condition