Genetic Testing for Cancer Risk Notes

Understanding Genetic Testing for Cancer Risk

Genetic testing can be valuable for individuals with a family history of cancer or those diagnosed with cancer without a clear family history. However, it's not universally recommended. Genetic tests can reveal risk factors for certain cancers. Before undergoing testing, it's crucial to understand the test's purpose and limitations in determining cancer risk.

What is Genetic Testing?

Genetic testing involves medical tests that identify specific mutations or changes in a person's genes. These tests are versatile, but in the context of cancer, they're used to detect gene changes associated with the disease. Understanding genes and how mutations can lead to cancer is fundamental to interpreting genetic test results.

Genetic Testing to Evaluate Cancer Risk

Predictive genetic testing identifies inherited gene mutations that elevate a person's risk of developing particular cancers. It may be recommended for:

• Individuals with a strong family history to check for inherited mutations. If a mutation exists, enhanced screening or risk-reduction strategies may be employed. For instance, testing for $BRCA1$ and $BRCA2$ gene mutations is common in families with a history of breast cancer, as these genes increase the risk of breast cancer and other cancers.
• Cancer patients, especially if the cancer was diagnosed early, is uncommon, or if there's a strong family history, to determine if an inherited mutation caused the cancer. This information can assess the risk of developing other cancers and inform testing decisions for family members.
• Family members of individuals with known inherited gene mutations to assess their risk and guide screening or risk-reduction efforts.

Most people, even those with cancer, don't require this type of testing unless there's a family history suggesting inherited cancer. Genetic counseling and testing might be advised for individuals with specific cancers or cancer patterns in their family.

Who Might Benefit from Genetic Testing?

Consider genetic counseling and testing if you have:

• Several first-degree relatives (parents, siblings, children) with cancer.
• Many relatives on one side of the family with the same cancer type.
• A cluster of cancers (e.g., breast, ovarian, and pancreatic) linked to a single gene mutation like $BRCA$.
• A family member with multiple cancer types.
• Family members diagnosed with cancer at a younger age than typical.
• Close relatives with cancers linked to rare hereditary cancer syndromes.
• Rare cancers (e.g., male breast cancer or retinoblastoma) in you or a family member.
• A particular ethnicity linked to higher mutation risks (e.g., Ashkenazi Jewish ancestry and $BRCA$ mutations).
• Physical findings associated with inherited cancer (e.g., numerous colon polyps).
• A known genetic mutation in a family member.
• Lab tests indicating a potential inherited gene mutation.

If concerned about your family's cancer history or risk factors, consult a healthcare provider about genetic counseling and testing. Remember, not all cancers have known mutations linked to increased risk.

What is Genetic Counseling?

Genetic counseling provides information to aid decisions about genetic testing. Counselors are trained and certified in this field, though other health professionals may offer counseling with varying training levels. It's appropriate to inquire about a counselor's training.

What Does a Genetic Counselor Do?

Genetic counselors offer guidance before and after testing:

• Assess your risk based on family history.
• Discuss risk management strategies.
• Explain available genetic tests.
• Interpret test results.
• Address privacy concerns.

They explain the testing process, its capabilities and limitations, and the emotional and familial impact of results, helping you decide if testing is suitable. Ultimately, testing and subsequent decisions are yours.

Before You Get Tested

Determine genetic testing's potential value for your situation by consulting your healthcare provider and seeking genetic counseling to understand what to expect. Your counselor can outline risks, benefits, potential results, and available options. Your healthcare provider can refer you to a genetic counselor, or you can find one through the National Society of Genetic Counselors.

Testing Cancer Cells for Gene Changes

Doctors may test cancer cell samples for gene or protein changes post-diagnosis. These tests inform prognosis and treatment decisions, focusing on acquired changes within cancer cells, distinct from inherited risk tests.

Home-Based Genetic Tests

Direct-to-consumer genetic tests are available but require careful consideration. Understand what the test assesses, its limitations, and reliability. Even accurate tests may have limited scope. These tests don't provide a comprehensive assessment of cancer risk and may overstate their helpfulness. A negative result may not fully account for your overall cancer risk. Genetic counselors offer crucial context to test results. Home-based tests shouldn't replace cancer screening or professional genetic counseling based on individual risk. Always consult your doctor, as genetic counselors can clarify expectations for test results.

What Might I Learn from Genetic Testing?

The value of genetic testing depends on your objectives and the test's capabilities. It can enhance understanding of disease risk and guide health decisions. A negative result can reduce anxiety for at-risk families, while a positive result can inform proactive risk management. If positive, your healthcare provider may recommend:

• Earlier and more frequent cancer screening.
• Specialized screening tests for high-risk individuals.
• Monitoring for specific signs and symptoms.
• Risk-reducing measures like medication, surgery, or lifestyle changes.

Early cancer detection often improves treatment success. Genetic testing indicates the presence of a gene variant or mutation, not a definitive cancer diagnosis. Therefore, testing reveals potential risks but not certain outcomes. A positive result doesn't guarantee disease development, and a negative result doesn't eliminate cancer risk, as lifestyle, environment, and age also play roles.

How Might the Results Affect My Family?

Consider the impact on your family before testing, including emotional and informational management. Discovering a potential for serious illness can be distressing, especially with prior family losses. Gene inheritance can evoke guilt or anger. A positive result may prompt testing among family members, informing their risk and management strategies. If the mutation isn't familial, testing can reassure relatives. However, not all family members may want to know their risk, particularly if management options are limited. Testing can induce anxiety and uncover sensitive family information like paternity or adoptions.

What if I Don't Know My Family's Medical History?

Disclose any lack of family medical history due to adoption, estrangement, or deceased relatives. An unknown history isn't equivalent to no family history. Adoptees can check for state laws allowing anonymous medical records from biological families. Estranged individuals can attempt contact for family history details, possibly through a doctor or mediator. While family history influences risk, lifestyle factors like tobacco or alcohol use, diet, exercise, weight, chemical exposure, infections, and radiation also significantly contribute. Your doctor will assess your overall risk and create a plan, potentially including genetic testing.

Will Testing Lead to More Medical Tests?

Genetic testing might lead to additional medical tests or procedures. For example, a gene variant increasing colorectal cancer risk may necessitate more frequent colonoscopies. While beneficial for prevention or early detection, these tests involve time, cost, and potential risks.

Is Genetic Testing Covered by Insurance?

Genetic testing can be expensive. While most insurance plans offer some coverage, it depends on individual factors and medical criteria. Certain extensive tests incur higher costs. Federal laws mandate coverage for some women at high risk for $BRCA1$ or $BRCA2$ mutations. Determine potential costs and coverage details beforehand. A genetic counselor can clarify coverage likelihood, pre-authorization, and billing policies. Some individuals opt to pay privately to maintain confidentiality.

Could the Test Results Lead to Discrimination?

The Health Insurance Portability and Accountability Act (HIPAA) protects genetic information in medical settings. The Genetic Information Nondiscrimination Act (GINA) further safeguards against workplace and health insurance discrimination based on genetic information for non-governmental organizations with over 15 employees. GINA defines genetic information as personal and family genetic test results, and knowledge of family genetic disorders. GINA prevents employers from discriminating in hiring, pay, or promotions based on genetic information, regardless of how it's obtained. Employers can't mandate testing or collect genetic information, except in limited situations like family leave or workplace hazard monitoring, and must maintain confidentiality. Health insurers can't deny coverage or raise premiums based on genetic information or services, including counseling and testing. GINA applies to various health insurance plans but doesn't override stronger state laws. It excludes life, disability, and long-term care insurance, and doesn't mandate genetic testing coverage. GINA doesn't apply to small employers (under 15 employees), military health plans, the VA, Indian Health Service, or Federal Employees Health Benefits Plans.

What About Other Privacy Issues?

Medical and pharmaceutical researchers require informed consent for studies involving tissue samples and DNA. Some labs offer options to allow or deny the use of leftover DNA for research post-testing. Employers can request genetic testing to monitor exposure to toxic chemicals, but not for hereditary cancer syndromes.

What Happens During Genetic Testing for Cancer Risk?

Genetic testing proceeds when deemed appropriate by you and your healthcare team, involving several steps and potentially multiple visits or calls:

• Information gathering
• Risk evaluation
• Education and informed consent
• Specimen collection and lab testing
• Sharing results with family members

Information Gathering

A genetic counselor, doctor, or nurse trained in genetic counseling gathers personal and family medical history. This includes your medical history (biopsies, surgeries, screening tests, gynecologic history, lifestyle factors, carcinogen exposure) and, if applicable, cancer details (type, biomarkers, occurrence of multiple cancers). A detailed family history is crucial, often collected via questionnaire, inquiring about cancer diagnoses and ages at diagnosis on both sides of the family. Confirm family illnesses with medical records or death certificates where possible.

Risk Evaluation

Based on gathered information, the counselor determines:

• Your cancer risk
• The potential benefits of genetic testing
• The specific gene changes to test for (single gene or panel testing)

The reasons behind these recommendations will be clarified.

Education and Informed Consent

The genetic counselor explains inheritance patterns, risks, benefits, costs, and limitations of testing, and identifies suitable candidates for testing within the family. Consider how results may affect you and your relatives, and discuss these concerns with the counselor. The counselor may suggest risk management strategies (lifestyle changes, early detection, symptom monitoring, risk-reducing medications, or preventive surgery). Expert counseling addresses concerns like increased risk, potential discrimination, and familial attitudes toward cancer. Cultural beliefs, support systems, and finances are also considered. The counselor helps you cope with test results, addresses fears, and aids in communicating results to family members. Confirm insurance coverage for genetic counseling and testing. Remember, genetic testing is a personal choice. After risk assessment and counseling, you can decide whether to proceed. If you proceed, you'll provide written informed consent. The informing process includes:

• The purpose of the test
• The rationale for offering the test
• The nature of the genetic condition being tested
• Test accuracy
• Benefits and shortcomings of testing including limitations of results
• Alternative testing options
• Screening or treatment options when applicable
• Further decision possibilities after results are given
• Consent choices to using results for future research purposes.
• Availability of support and further assistance
• Your right to refuse testing
• The timeframe for test results and discussions
• Genetic discrimination and protections

Specimen Collection and Lab Testing

After consent, lab tests are conducted on bodily samples typically including blood, saliva, or cheek cells but other tissues may be used. Individuals with active blood cancer or a history of bone marrow transplant may need alternative samples. No dietary restrictions are put in place before the test. Inquire about result turnaround time and follow-up appointments.

Getting the Test Results

The genetic counselor shares the test results with you, possibly via phone or at a scheduled appointment, usually 2-3 weeks later. Request a copy of the test result. Consider bringing a support person to emotional support, understanding, note taking, and/or to help share results with family members. Testing outcomes include:

• Positive
• Negative
• Variant of uncertain significance (VUS)

If a result is positive

A positive result signals a mutated gene that may increase cancer risk or may explain an already existing cancer. It could also predispose an individual to developing other cancers. After discovering a risk for developing cancer, many people commonly become concerned. Results, if positive, may also indicate higher risks for certain family members, inducing more stress. After testing, uncertianty will still exist. Results from the test will not change what state of health you are in and do not indicate whether an individual has cancer or not currently. Further steps can be discussed with the support of a healthcare expert to determine best plans to reduce risk or discover the on-set of cancer early.

If a result is negative

A negative result indicates no mutation was found in the tested genes. But this could also mean that your mutation is linked to cancer, but it cannot be located using current known testing methods. Testing only tests the genes it looks for and not every possible gene mutation.

In families with a known gene mutation
If positive that you do not contain the family's known result can be very comforting. Though this does not mean that cancer risk is zero.

In families without ak known gene mutation
a negative result can mean that you might have a mutation still that is linked to cancer in the family but cannot be found in current testing measures. Another possible reason being you have a mutation in a gene that has not been found or discovered yet.

If a result is VUS

Can cause frustration, anger, and anxiety in users as the result isn't clear and there is not timeline in when it may become clear. Usually remaining in contact with a health care provide is important for the updates that may become apparent.

What if Genetic Testing Shows an Increased Cancer Risk?

Risk management becomes a priority if the results show a positive gene mutation that could increase cancer risk. Strategies and options include: lifestyle changes, chemoprevention, and preventive surgery, Your health care provider may recommend one or many of the options listed above. The risk and benefits should be weighted and discussed before deciding the best decision and course of action.

Lifestyle changes: healthy choices and/or behaviors to mitigate cancer risk

Chemoprevention: medicine is used to prevent certain cancer types

Preventive/prophylactic suregery: removal of healthy glands to help prevent cancers from starting in those areas.

Sharing Results with Family Members

It is important to think ahead and make a plan to share the information with others so it is easily accessible to the family members who are also at risk.

Sharing Results with Family Members About Genetic Testing

Sharing genetic test results with family members is allows them to learn what the individual being tested went through and offer valuable context that the tested family members can use to estimate their own potential risk to cancer.

Risk between relatives

• First-degree biological relatives have about a $50\%$ chance of sharing these same gene mutations.
• Second-degree biological relatives have about a $25\%$ chance of sharing these same gene mutations.

Sharing conversation and ways to have it
The counsellor can help develop a family member lettter. This letter can be sent on it's own or given and discussed in a more personal setting. People can talk with family about genetic testing and test results in many ways, such as a phone call, face-to-face conversation, text, email, or letter. Some people may come up with valid reasons for not sharing results with family because the time isn’t quite right. But there really is no best time for everyone and every family.

Ways to encourage opening the conversation

• I recently had genetic testing. Would you be interested in hearing about it? I’d like to tell you about my genetic test results. I think my results could help you too
• I learned some information that might be important for you to know, too. Can I tell you about it?
• After my cancer diagnosis, my doctor had me meet with a genetic counselor. They helped me understand that my cancer risk was higher because I have a gene mutation. They told me my close relatives could have the same gene mutation. Can I give you some information so you can talk to your doctor about it?
• I am going to send you an email that has my recent genetic test results. I want you to have this information so you can decide if genetic testing might be something you could benefit from having. Your doctor can help you decide.

Tips to stay comfortable while sharing results

1. Make a list of who you want to share your genetic test results with. Decide how you will share the information: in person, or by phone, email, text or letter.
2. Pick a date and write it on your calendar. Consider choosing an upcoming family get together or sending your family member an email or text in advance.
3. Write down what you are going to say ahead of time or practice with a friend. Your doctor or genetic counselor can give you advice on how to explain your results, since they know your situation best.
4. Prepare for possible reactions It’s important to understand and address your own feelings before talking to your family members. It’s also important to be aware that your family members might feel differently. It’s hard to know how family may react to the news. It’s common for people to feel a range of emotions when learning about a positive genetic test result or family cancer syndrome – whether it’s a family member who was tested or if they were tested themselves.

Sharing results with children
When and how much to tell a child, it's best to consult with medical experts such as pediatricians, genetic counselors, and doctors to help with discussing options.

Questions to Answer Before Talking to Family Members

• Do I have all the information I need? What specific information am I going to share?
• Who is at risk in my family? Are there certain family members to reach out to? What information am I comfortable sharing in person? What information would I prefer to share by letter or email or text?
• How do my family members like to be communicated with? Would they prefer a chat over coffee or an email?
• How am I feeling about sharing this information? Would it be helpful if I talked to someone else before talking to family or helpful to talk to one family member before others?
• Are there any family or cultural beliefs I need to consider before telling my family?
• What emotions might my family member(s) feel when I tell them about this?
• Do I have good resources handy to share with my family members? Would it be helpful to have my genetic counselor write a family letter for me that includes the details of my test results?