Typically, the growth and division of cells is tightly managed and there are many genes that regulate these processes.

When certain genetic changes occur within cells, the way that they grow and divide can become atypical and develop into cancer. There are several factors involved in genetic changes that may lead to developing cancer.

While environmental and lifestyle factors can lead to some of these changes, an individual’s genetics also play an important role. It’s possible to inherit some gene changes that increase your risk of developing certain types of cancer.

Genetic testing is available to help detect some of the genetic changes that can increase the risk of developing cancer. Keep reading to learn more about this testing, its potential benefits, and who’s a good candidate.

What is genetic testing for cancer?

Genetic testing is a tool that can be used to learn about inherited cancer risks. Some examples of cancers where specific genes appear to play a role in cancer risk include:

breast cancer
colorectal cancer
prostate cancer
ovarian cancer
pancreatic cancer

Other cancers where specific genes appear to play a role in cancer risk include some cancers of your:

skin
thyroid
kidneys

Genetic testing looks for variations in genes that are associated with an increased risk of cancer. The National Cancer Institute estimates that inherited gene variants contribute to 5 to 10 percentTrusted Source of all cancers.

There are many options for genetic testing. For example, your healthcare professional may recommend a test to look for variants in a single gene. There are also panel tests that can detect variants in several genes.

What to expect during genetic testing for cancer

There are several components that are associated with genetic testing for cancer. Let’s explore each of them below:

Risk assessment

A healthcare professional, such as a doctor or genetic counselor, will look at both your personal and family medical history to determine if you’re a good candidate for genetic testing.

Genetic counseling

A genetic counselor will work to give you additional information that can help you decide if you want to get tested. This can include information on:

how cancer can be inherited within families
how specific gene variations can increase your risk of developing cancer
the way that genetic testing works
the limits of genetic testing
the pros and cons associated with genetic testing
the potential medical implications of the test results
how your results may affect your mental health or relationships with your family members

Genetic counselors are also important after testing. They can help you interpret your results and discuss what to do moving forward.

Informed consent

If you decide to get tested, you’ll be asked to sign an informed consent document. This document confirms that you’ve been told about things like:

the purpose of the test and why you’re being tested
the accuracy of the test as well as its limitations
the various pros and cons of testing
the potential implications of the results
any potential alternatives to testing
your privacy rights
your right to refuse testing

Sample collection and analysis

The testing procedure typically involves collecting a blood sample from a vein in your arm. However, it may also be a sample of:

blood
saliva
cheek cells

The sample is then analyzed by a lab that specializes in genetic testing. It’s possible that it can take several weeks for results to be ready.

Receiving the results

When results are available, they’re typically sent to your genetic counselor, who will then contact you to discuss them and develop a plan for next steps.

The different results that you can receive are:

Positive. A gene variant that increases the risk of cancer is detected. Your genetic counselor will talk about your risk level as well as potential steps, some of which can include:
getting screened for cancer more frequently or at an earlier age
implementing lifestyle changes that can help reduce your cancer risk
removing potential at-risk tissue, such as having a mastectomy if you’re at a high risk of developing breast cancer
taking medications that lower your cancer risk (chemo prevention)
Negative. The test doesn’t detect a specific variant that increases cancer risk. However, it’s important to remember that a negative test result doesn’t mean that you’ll never develop cancer over the course of your lifetime.
Unknown significance. In this case, a genetic variant is detected, but its significance as far as cancer risk is currently unknown.

What are the benefits of genetic testing for cancer?

Genetic testing for cancer can have several potential benefits. These can include:

Peace of mind. If a certain type of cancer runs in your family, a negative test result can give you peace of mind that you haven’t inherited certain variants.
Preventative actions. Learning that you have a variant that increases your cancer risk can help you to take preventative steps early and look out for potential cancer symptoms, if they develop.
Family testing. It’s possible that immediate family members can learn about their cancer risk from your results. It may also encourage them to get tested.

Who should have genetic testing?

A healthcare professional may recommend genetic testing for cancer when:

you have a family or personal history of a specific cancer
testing can effectively determine the presence of gene variants that increase the risk of developing this cancer
the results of the test can be used to help guide preventative measures or future treatments

Now let’s look at some examples of situations where you may consider genetic testing for cancer.

Family history

Someone with a strong family history of developing certain types of cancer may choose to get tested to find out their risk level. This is typically the case if:

more than one immediate family member (parents, siblings, or children) has developed cancer
multiple people on one side of a family have been diagnosed with the same type of cancer
cancers run in a family and have already been linked to a specific gene variation
people in a family have been diagnosed with multiple types of cancer or have been diagnosed younger than 50 years old

For example, someone with both a mother and sister that have been diagnosed with breast cancer may choose to be tested for variations in the BRCA1 and BRCA2 genes.

If the test has a positive result, this person can then begin to take preventative steps. These can include things like:

more frequent cancer screenings
lifestyle changes specific to their health needs
preventative surgeries

Personal history

A person that’s already been diagnosed with cancer may wish to see if an inheritable factor is present. This is particularly true if they have a family history of certain types of cancer or if they received their diagnosis younger than 50 years old.
Family members

Knowing that a relative has a specific genetic variation that increases cancer risk can be beneficial for family members as well. It may prompt them to get genetic testing themselves.

Is genetic testing accurate?

Genetic testing isn’t perfect. If you do receive a positive test result for a specific gene variant, it doesn’t mean that you’ll develop cancer. It just means that your risk of developing cancer is increased.

Additionally, remember that all cancers are different. Because of this, different types of variations are associated with different levels of risk. Your genetic counselor will discuss this with you when you get your results.

How much does genetic testing cost?

According to Breastcancer.orgTrusted Source, the cost of genetic testing for cancer can vary greatly and can be between $300 and $5,000. How much genetic testing costs can depend on the type of test as well as how complex it is.

What exactly is covered will depend on your specific health insurance plan. Many plans will offer some coverage if genetic testing is considered medically necessary.

If you’re considering genetic testing for cancer, contact your insurance provider before getting tested. They can help inform you about what is and isn’t covered.

What about home-based tests?

Recently, home-based genetic testing has increased in popularity. These tests typically involve using a swab to collect a sample from your mouth. You then mail this sample back and get your results by:

mail
phone
secure website

You may be curious if home-based genetic tests are good for determining your cancer risk.

Overall, it’s best to talk with a healthcare professional if you’re interested in genetic testing to assess your cancer risk. Some reasons for this include:

Receiving genetic testing through your healthcare professional gives you access to counseling that can help you to understand your results and to develop a plan going forward.
Home-based tests often detect common genetic variants that may be associated with a very minor cancer risk. This can potentially cause alarm when you receive your results.
A home-based test may only look at a specific number of variants, meaning that it could miss some others. That means that a negative result could be misleading.
The privacy of your results may not be ensured. If you’re using a home-based test, be sure to carefully review the company’s information disclosure policy first.

Takeaway

Genetic testing can help determine if you have certain genetic variations that place you at an increased risk of developing cancer. It’s often done when you have a family or personal history of certain types of cancer.

There are many benefits to genetic testing. For example, a negative test result may offer some peace of mind. Or, a positive result could help you start taking steps that can prevent cancer from occurring.

Genetic testing does have limitations. A positive test result doesn’t mean with certainty that you’ll develop cancer, Meanwhile, a negative test result doesn’t mean that you’ll never develop cancer over the course of your lifetime.

A healthcare professional or genetic counselor will work with you to help you decide if genetic testing is right for you. If you do decide to get tested, they can also walk you through what the results mean as well as discuss next steps.