What is genetic testing?
Genetic testing is a blood test that looks for changes, called alterations or mutations, in genes. These changes can cause disease, or place someone at higher risk of getting a certain disease, such as cancer. All cancer starts with gene changes at the cell level. Most of these gene changes are not inherited – about 80 percent of all cancer happens because of damage to cells and their genes acquired over a lifetime.
But, some people can inherit a specific gene change that puts them at risk to get cancer. About 5 to 10 percent of cancers are influenced by an inherited gene change. Genetic testing can tell you if you inherited a gene change that could cause cancer. Our doctors may suggest genetic testing to individuals who have a family history of a particular cancer, or patterns of disease. Genetic testing, as part of cancer risk assessment, is done in specialized laboratories by trained professionals.
Your genetic counselor will review your medical and family history in order to determine the personal and inherited factors that could affect your risk of developing cancer.
The counselor will help you understand the influence of these different risk factors and help to coordinate genetic testing, if appropriate.
How can genetic testing be helpful?
With the help of one of our cancer risk counselors, genetic testing can:
- Tell you if you inherited a specific genetic change
- Tell you If you did not inherit a specific genetic change
- Help explain your risk of getting cancer
- Identify what you can do to lower your risk of cancer
If you already have cancer, genetic testing can
- Help you with your treatment plan
- Help you learn your risk of getting a second type of cancer
- Help your family members learn if they have inherited a specific genetic change
- Help explain other family members’ test results
How long does it take to get my genetic test results?
Genetic testing can take anywhere from two weeks to several months to complete.
What are multigene panels?
A multigene panel is a genetic test that looks at dozens of genes related to specific or related types of cancer in a single test, through new technology called Next Generation Sequencing. Fox Chase began offering multigene panels to all eligible patients in 2013 and created new education tools to help patients understand these panels. Our team is here to provide support and education to make sure every patient is comfortable with the information they receive from multigene testing.
Some of the most common cancer genetic tests are for the BRCA1 or BRCA2 genes related to inherited breast and ovarian cancer, or the Lynch syndrome genes related to inherited colon, stomach, uterine, and ovarian cancers. This type of testing is often costly and testing for more than one genetic syndrome is can be difficult to do, which is why multigene panels can be a way to keep costs down.
Multigene panels can also test for more recently-discovered genes that may have been too expensive to test for in the past. Patients who have had negative genetic testing in the past may want to consider further testing with a multigene panel.
But there are some drawbacks of multigene panels. One challenge comes with the discovery of new genes, about which the medical community has little information. Multigene panels also carry a higher possibility of an unclear test result called a genetic variant of uncertain significance. This type of result is often too difficult for doctors to interpret for healthy family members.
We continue to offer syndrome-specific testing because this type of test has the lowest possibility of an unclear result, and is sometimes faster, which is important for cancer patients who need genetic testing information to help shape their treatment. If you’re unsure about whether a multigene panel is right for you, our genetic counselors are here to help. Our Risk Assessment Program offers genetic counseling to patients with a personal or family history of cancer. They will review your testing options, so you can make a decision that’s right for you and your family.