Approximately 10% of all cancers have a strong hereditary component, according to the Society of Gynecologic Oncologists (SGO), which estimates that more than 500,000 American women are at high risk of developing hereditary cancers, such as breast, ovarian, colon and uterine cancers. Usually testing can indicate whether or not you have a gene abnormality or mutation. That information, taken in conjunction with your health profile and family history, must be evaluated by a trained genetic counselor who can then analyze and predict your risk of developing the disease. Other variables that affect development of the disease — such as environmental exposure, diet and lifestyle — are also very relevant to risk. According to Danielle Campfield, MS, a genetic counselor at Yale University School of Medicine in New Haven, Connecticut, you may want to consider genetic testing if you have any of the following…
- A personal or family history of cancer at unusually early ages (e.g., breast cancer under 45 or colon cancer under 50).
- Multiple relatives on the same side of the family with the same cancer or related cancers (e.g., breast and ovarian, or colon and uterine/ovarian).
- A family history of rare cancer (e.g., male breast cancer).
- More than one diagnosis of cancer in the same individual (e.g., breast and ovarian cancer in one person or colon and uterine cancer in one person).
- Jewish ancestry in combination with a personal or family history of breast or ovarian cancer.
- A family history of a known genetic mutation.
BENEFITS AND RISKS OF TESTING
While the actual process of taking the test is simple (a sample of DNA is taken from blood, bodily fluids or tissue scraping), what you do before and after the test takes great thought and consideration. The first step is always a consultation with a genetic counselor, who will discuss the pluses and minuses of genetic testing — for there are certainly two sides to the decision. He/she will review your personal and family medical history and help you make a decision about whether to go forward.
But, says Naomi G. Tamerin, MD, a bioethicist in Greenwich, Connecticut, no one should think of this as merely "a simple lab test" since there are many ramifications, including emotional and legal ones. In her view, the downside pales compared with the benefits. These can include…
- Reduction of uncertainty. Positive or negative, many people find having the information provides relief, delivering more control and the ability to make informed decisions about future screenings and preventive measures, if any are known.
- For negative results, better survival odds. If results indicate that you’ve inherited a genetic predisposition for a certain disease, your physician can screen you more often — most diseases are more easily cured or managed when diagnosed early, even if they can’t be prevented.
- Reduction of risk. In many cases, if you know you are at risk to develop a particular disease, you can make lifestyle changes, increase your surveillance, take medication or consider other preventive steps. For example, people at risk for colon cancer can schedule earlier and more comprehensive screenings, follow a stricter diet and work with their physician on other preventive measures.
However, others feel that genetic testing isn’t always helpful and have concerns that this kind of screening is a double-edged sword. Here are some of the commonly cited issues, along with our experts’ reactions to them…
- Uncertain results. The results of testing are not always black and white. "Surprisingly," Campfield says, "we have found that one of the greatest risks of genetic testing is the possibility that your test results will be misinterpreted." She reports that the Yale Cancer Genetic Counseling Program has now seen several patients who have either had prophylactic surgery or considered it, based on results wrongly interpreted by their physician. Why? One of the main issues is that genetic testing companies are aggressively targeting provider offices and encouraging them to order their own genetic testing services. This is why test results should always be evaluated by a certified genetic counselor, explains Campfield, who has received extensive, specialized training.
- Anxiety, guilt and family dissension. Dr. Tamerin points out that genetic testing may or may not be what’s best for everyone in the family. Individuals often vary in how they react to the news they get. Your decision to pursue genetic testing, not the results of your test, certainly affects your siblings and children as well. Here again, a genetic counselor can be helpful in discussing and resolving probabilities and issues.
- Cost. In the past, the costs for these tests (which can range up to several thousand dollars) were rarely covered by insurance. The good news, says Campfield, is that this is beginning to change. Some health insurance plans cover genetic testing when recommended by your doctor. Check in advance with your insurance carrier to see whether it will cover these tests. If not, your physician may be able to negotiate coverage in the face of a strong family history.
- Discrimination. Although there have been few documented cases of discrimination due to genetic testing, this is a particular concern among patients pursuing genetic counseling and testing for hereditary cancer syndromes. However, despite well-documented patient concerns and anecdotal reports of discrimination based on genetic information, there is little or no solid data to support these concerns. If this issue arises with an employer or insurance company, consult your genetic counselor — or your attorney — about federal and state laws that prohibit discrimination.
SLOW TO SPREAD THE WORD
Given the speed at which genetic discoveries are being generated, it is understandable that much of the public knows little about what’s available — but surprisingly, the medical community, too, may not be aware of the conditions for which tests now exist. People continue to die from cancers with suspected genetic links that might have been prevented. For example, 5% to 10% of breast cancers are linked to detectable genetic mutations that may run in a family. In particular, breast cancer BRCA1 and BRCA 2 mutations increase the lifetime risk of breast cancer to between 36% and 85% of women, and ovarian cancer from 16% to 60%, according to the National Cancer Institute. Yet few women, even in families with a history of ovarian or breast cancer, get tested for this mutation, and as a result, many may unnecessarily put themselves at greater risk of losing their lives to the hereditary forms of these cancers, since these may be prevented or detected at an early, treatable stage.
While there are certainly benefits to genetic testing for treatable and sometimes preventable diseases such as cancer, the issues become considerably weightier with devastating, unpreventable and incurable illnesses such as Huntington’s disease — especially since this is a genetic disease where presence of the gene mutation confers virtually 100% likelihood of developing the disease. Even in this case, however, proponents argue that knowing what the future holds enables you to make practical plans. Often siblings make different decisions, with some choosing to learn their results and others opting to wait and see what happens.
In the long run, it’s always up to you. If you are concerned about the possibility of developing a hereditary disease, consider making an appointment with a genetic counselor to discuss whether testing is right for you. Most major hospitals and cancer centers have genetic counseling and testing services. Campfield cautions that some genetic testing companies advertised on TV or in magazines may not have counselors that are adequately trained in genetic testing. To find a genetic counselor in your area, log on to the National Society of Genetic Counselors Web site, http://www.nsgc.org/resourcelink.cfm. To find out if a counselor has certification, go to the American Board of Genetic Counseling’s Web site, www.abgc.net.
A great center for genetic testing, natural healing, and detoxing is SANOVIV, www.Sanoviv.com
Naomi G. Tamerin, MD, physician-bioethicist in Greenwich, Connecticut.
Danielle Campfield, MS, genetic counselor, Yale University School of Medicine, New Haven, Connecticut.