Genetic Counseling: A Tool for Decoding Inherited Cancer Risk

Health Writer
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When Angelina Jolie announced in 2013 that she had the inherited gene mutation, BRCA1, which greatly increased her risk for breast and ovarian cancer, she shone a spotlight on the topic of inherited cancer. If you have multiple cases of cancer in your family, you may also question whether you have an inherited gene mutation that heightens your cancer risk. Genetic counseling can give you crucial answers.

A genetic mutation or inherited cancer syndromes may confer a 20 percent to 80 percent increased risk for cancers such as breast, ovarian, colon, prostate, and thyroid cancers. Yet even if you have multiple cases of cancer in your family, your fears of an inherited cancer syndrome may be overblown or unrealistic.

A genetic counselor, in one or two sessions, can provide an accurate assessment of your risk for inherited cancer.

“Genetic counseling is a tool to understand the pattern of cancer within a family, and to understand if your risk for inherited cancer is elevated enough to merit genetic testing,” says Joy Larsen Haidle, past president of the National Society of Genetic Counselors and a certified genetic counselor at North Memorial Cancer Center in Robinsdale, Minnesota.

“At the end of a genetic counseling assessment, people will walk away with a more complete understanding of their level of risk, and steps they can take to modify that risk. So, it can feel very empowering,” Larsen Haidle adds.

Just to be clear, however, most cancer cases are not due to an inherited genetic mutation. They are often due, instead, to mutations in our genes that come from the environment, lifestyle, or old age — as cancer is most common in the elderly. Yet increasing numbers of people are interested in and seeking out genetic counseling and testing for inherited cancer syndromes. The reasons are myriad, including the increased publicity surrounding Angelina Jolie’s case, as well as the improved technology and lower costs for genetic testing, according to Larsen Haidle.

Genetic counselors analyze your family tree for evidence of the signs of genetic cancer — or diagnoses and deaths from cancer in four generations of your family, including parents, siblings, grandparents, great-grandparents, and first cousins. Genetic counseling also includes a discussion of preventive health steps you can take to reduce your cancer risk. These steps can include lifestyle changes, surveillance with tests such as mammography (often performed more frequently than in the general public), or even preventive surgeries, according to Larsen Haidle.

People are referred to a genetic counselor by their physician, or they may seek out a genetic counselor because they are concerned or worried about their cancer risk.

“Patients sometimes walk into a genetic counseling session with a very accurate sense of their risk, while others have wildly exaggerated guesses about their risk, or greatly underestimate it,” says Nicolette Chun, senior genetic counselor in the cancer genetics and genomics division of Stanford Healthcare in Palo Alto, California.

The signs of an inherited cancer syndrome in you or your family can include:

  • Cancer at a young age (before age 50).

  • Multiple close family members with the same type of cancer or with rare cancers.

  • Cancer in a gender that is usually not affected, such as breast cancer in males.

  • Bilateral cancer, or cancer on both sides of the body, such as cancer in both breasts.

  • Two or more types of cancer in the same family member.

How to assemble a family history

Assembling a family history of cancer may take some detective work on your part. Although you may know about cancer diagnoses in your immediate family, you may not have much information about diagnoses and deaths from cancer in more far-flung relatives, such as grandparents, great-grandparents, and cousins. If possible, it helps to speak to relatives who you think are the most knowledgeable about the cancers in your family.

You can also request medical records if you know where your family member was treated, or your grandparents’ or great-grandparents’ death certificates from city health departments. In many cases, you can obtain these medical records if you are the executor on the estate, or if you have permission from the executor. You may also need to submit documents, such as your relative’s will, to obtain medical records.

In previous generations, cancer was often shrouded in secrecy. So, cancer — particularly female cancers — may have been described in vague terms within a family, such as a “female condition,” “abdominal cancer,” or “stomach cancer.” These illnesses may have been simply a benign growth, such as a uterine fibroid, or more serious ovarian or uterine cancer, according to Larsen Haidle. That’s why obtaining health records or a death certificate can be crucial, as they can provide an exact diagnosis or cause of death.

A pattern of inherited cancer is not always obvious to the untrained eye, so a genetic counselor will work with you to obtain information about cancer cases on both sides of your family. Yet multiple cases of cancer on one side of your family does not always mean an inherited cancer syndrome, particularly if they occurred over age 60, because cancer is such a common disease, according to Chun.

If any of your relatives have undergone a genetic test for a cancer mutation, it’s also vital for you to obtain the results if they are willing to share them. The records of such tests, including what genes were tested and whether a mutation was found, are important pieces in the puzzle of your family history of cancer. These facts can help illuminate whether you might have enough risk to undergo your own genetic test, Chun adds.

Reasons for genetic testing

Even without a clear family history of cancer, patients diagnosed with cancer early (before age 40 or 50) are often encouraged to undergo genetic counseling. Cancer at a young age is one of the strongest signs of inherited cancer, Larsen Haidle says. For a cancer patient, discovering a genetic mutation may not only provide important information for the future, but can change his or her treatment plan.

The presence of a mutation in a young cancer patient may mean a heightened risk for being diagnosed with a second cancer. So these patients may want to consider preventive measures that will reduce their risk of another cancer diagnosis as part of their treatment or follow-up plan. These measures may include stepped up surveillance tests or preventive surgeries, such as total mastectomy, in which most of the breast tissue is removed.

“Undergoing genetic testing while you are also dealing with a new diagnosis of cancer can demand fortitude,” Chun says.

“A genetic counselor will help you decide the pros and cons of undergoing genetic testing right away, or whether it might be better to wait for a less stressful time,” she adds.

As recently as several years ago, genetic testing was often prohibitively expensive — costing as much as $4,000 for each mutation tested, Larsen Haidle says. Now, however, gene sequencing tests are available that will assess mutations in panels of genes known to enhance risk for one or more cancers. These tests cost between several hundred dollars to $5,000, depending on what is tested, and are usually covered by insurance. If you don’t qualify for insurance coverage of a genetic test based on your risk factors, however, the cost of some tests is low enough that you may choose to pay out-of-pocket.

Scientific advances have greatly expanded our understanding of which mutations may contribute to inherited cancer risk, and how much a given mutation can heighten cancer risk. Years ago, genetic tests could only provide results on mutations in a handful of gene mutations known to contribute to inherited cancer. Yet now testing can analyze a wide variety of genetic mutations that may confer moderate to high risk for cancer at lower cost than ever before. As a result, genetic counseling and testing has become more accessible and informative, according to Larsen Haidle.

Chun recalls the case of a woman who had early breast cancer years ago, and did not go through genetic counseling or testing when she was diagnosed.

“Now that there is better testing available, she decided it was time to come in for genetic counseling, and possibly genetic testing," Chun says. "It was a real relief for her to finally get answers about her inherited risk for cancer."

To find a genetic counselor in your area, or one who provides counseling sessions by phone, visit the National Society of Genetic Counselors website.

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