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Some people inherit changes (mutations) in certain genes that increase their risk of prostate cancer (and possibly other cancers).

Genetic testing can look for mutations in some of these genes. Genetic testing can be helpful in some situations. But not everyone needs to be tested, and it’s important to understand what genetic testing can and can’t tell you before these tests are done.

Inherited gene changes that can increase prostate cancer risk

Inherited mutations in several genes have been linked to an increased risk of prostate cancer, including:

• BRCA1 and BRCA2
• CHEK2
• ATM
• PALB2
• DNA mismatch repair genes (such as MSH2, MSH6, MLH1, and PMS2) (linked with Lynch syndrome, also known as hereditary non-polyposis colorectal cancer, or HNPCC)
• HOXB13

Other inherited gene mutations may account for some hereditary prostate cancers as well. To learn more about these genes, see What Causes Prostate Cancer?

Why might genetic counseling and testing be helpful?

The main benefit of genetic testing is that it can help you better understand your risk for a certain disease, such as prostate cancer. Genetic testing isn’t perfect, but it can often help you make decisions about your health. Here are some ways in which the results of genetic testing might be helpful:

If testing shows you have a gene mutation that raises your risk of prostate cancer (and possibly other cancers, depending on the gene change), it might lead you to:

• Take steps that could lower your risk.
• Start getting screening tests at a younger age, which might help find cancer early.
• Be aware of possible signs and symptoms of cancer, so you can see your health care provider earlier if you have them.
• Inform your family members about the gene mutation, so they can decide if they want to be tested for it as well.

If you have prostate cancer and genetic testing shows you have an inherited mutation, this might affect your treatment options. For example, some targeted drugs are only likely to be helpful if your cancer cells have certain gene mutations. The test result might also lead you to inform your family members, who can then decide if they want to be tested.

If testing does not find a gene mutation, it can help reassure you and might help lessen your anxiety about your prostate cancer risk (as well as that of your family members). At the same time, it’s important to know that genetic testing has limits. For example, not all tests look for the same gene changes. Tests often look for the most common gene mutations, but they don’t look for every gene change that might affect your risk. This means it’s possible you might still have an inherited gene mutation even if testing doesn’t find one.

And of course, not having an inherited gene mutation doesn’t mean your prostate cancer risk is zero. It means you have about the same risk as most other men, and you can decide what steps you want to take based on this information.

The results of genetic testing aren’t always straightforward. This is why genetic counseling is an important part of the genetic testing process. Before testing, a health care provider trained in genetic counseling can explain what the tests can tell you, which can help you decide if testing is right for you. Then, if testing is done, they can help you understand the results and what could they mean for you.

Who might be advised to get genetic testing?

Not all men need genetic testing for prostate cancer risk. Genetic counseling and testing is more likely to be recommended if there’s reason to think you could have an inherited gene change that raises your risk of prostate cancer.

Some expert groups have developed guidelines for who should consider genetic counseling and testing for prostate cancer risk. These guidelines can be complex, and they vary slightly between groups, but in general they include two main groups of people:

If you’ve never had prostate cancer, genetic counseling and testing might be recommended if, for example:

• There is a known gene change (such as in one of the BRCA genes) that runs in your family.
• You have a strong family history of prostate cancer (or certain other cancers) that suggests one of these gene changes might run in your family. For example, if many family members (related by blood) have had cancer, if there have been unusual cancers in your family (such as breast cancer in a man), or if cancers have appeared at a younger age than usual.

If you have prostate cancer, genetic counseling and testing might be recommended if, for example:

• Either of the conditions above are true.
• You’ve also had another type of cancer (especially breast cancer).
• You are of Ashkenazi Jewish descent (and therefore at higher risk for a BRCA gene mutation).
• Your prostate cancer has spread to other parts of your body.
• Your prostate cancer has high-risk features, or it includes intraductal carcinoma.
• Your prostate cancer cells have been tested and found to have a gene change that might have been inherited. In this case, genetic testing can show if the change is inherited (and therefore in all the cells of your body), or if it’s only in the cancer cells.

Considering genetic counseling and testing for prostate cancer risk

If you’re concerned about your risk because of a personal or family history of prostate cancer, talk with your doctor about whether genetic counseling and testing might be a good option for you.

Your doctor will probably want to know more about your family history and other factors to get a better idea about your risk of having an inherited gene mutation that increases prostate cancer risk.

Your doctor might suggest that you could benefit from speaking with a genetic counselor or other health care professional trained in genetic counseling. They can review your family history in detail to see how likely it is that you might have an inherited gene mutation.

The counselor can also describe genetic testing to you and explain what the tests might (and might not) be able to tell you, which can help you decide if genetic testing is right for you.

Genetic testing is covered by many health insurance plans, but it might not be covered (or might be covered only partially) by some of them.

If you do decide to get tested, the genetic counselor (or other health professional) can also help explain what the results mean, both for you and possibly other family members. To learn more about genetic testing in general, see Genetic Testing for Cancer Risk.

How genetic testing is done

Genetic testing can be done on samples of blood or saliva, or from a swab of the inside of a cheek. The samples are sent to a lab for testing.

There are many different mutations in genes known to be related to prostate cancer risk. Testing can be done to look for one (or a few) specific mutation(s), or more extensive testing can be done to look for many different mutations. For example:

• If someone is being tested because they have a family member with a known BRCA gene mutation, testing might focus only on that specific mutation.
• In people of Ashkenazi Jewish descent, testing might focus on the specific BRCA mutations that are most common in this group of people.
• If there’s no reason to suspect a specific gene change, testing will likely look for many different gene mutations.

Getting the results of genetic testing

Genetic test results are usually available within 2 to 3 weeks. The results might come back as:

• Positive for a mutation that was tested for. If the test does find an important mutation, there might be steps you can take to help lower your risk of prostate cancer (or other cancers), or to find it early, when treatment is most likely to be successful. If you’ve already been diagnosed with prostate cancer, a positive result might affect your cancer treatment options. A positive result might also have implications for your family members.
• Negative for the mutation(s) tested for. It can be reassuring to find out that the test didn’t find a mutation that increases your risk. But it’s important to know that genetic test results can’t always guarantee that you’re not at increased risk. For instance, you might have a gene change that was not tested for.
• Inconclusive. In some cases, the test might not be able to tell for sure if you have a gene mutation.
• Positive for a variant of unknown significance (VUS). This means that the test found a gene change (variant), but it’s not known if this particular change affects your risk.

The results of genetic testing can sometimes be complex or confusing, which is why it’s important to go over them with a genetic counselor or another health care professional trained in genetic counseling. They can explain what the results might mean for you (and possibly other family members).

To learn more about the process of genetic testing and the different types of test results, see What Happens During Genetic Testing for Cancer Risk?