Here we answer some commonly-asked questions about genetic testing for cancer.
Q: Is cancer hereditary?
Not all cancers are hereditary. It is estimated that only 5-10% of all cancers are considered to be inherited. That is, individuals within a family may inherit a predisposition to develop a certain type of cancer. This inherited factor is called a gene. Inheriting an altered (or mutated) gene is what may predispose a person to develop a certain type of cancer.
Q: What are the most common features of hereditary cancer?
Hereditary cancers typically are ones that:
- affect multiple relatives on the same side of the family
- appear at a relatively early age, usually before age 50
- affect different generations within the family
- involve multiple cases of cancer occurring in the same relative
- may show up as unusual or “rare” types of cancer occurring in multiple relatives within a family
If several of these “hereditary” features are present, it may increase the likelihood that a gene mutation is present in the family.
Remember, it is not uncommon for a person to have a relative with cancer. Having a relative with breast cancer, for example, does not necessarily mean that there is a breast cancer gene in your family.
Q: What is genetic testing and how might it be helpful?
Genetic testing looks for mutations within specific genes. Having a gene mutation indicates that a person is at increased risk of developing a particular type of cancer. For individuals who have had cancer, this test result may indicate an increased risk for another cancer. Having a gene mutation does not mean a 100% chance that cancer will develop.
Genetic testing can be helpful in guiding the medical management decisions
patients and their family members choose to make. For instance, carriers of
a particular gene may choose to have more aggressive screening tests done on
a regular basis. Or, they may consider other options that may lower the risk
of cancer. It may also provide cancer risk information to family members.
Q: What are the most common genetic tests for cancer?
Currently, genetic testing is available for:
- Hereditary Breast and Ovarian Cancer
- Hereditary Colon Cancer
- Hereditary Melanoma
It’s also possible to test for certain other rare cancer syndromes, sometimes through research studies.
Q: Who may be at hereditary risk for breast and ovarian cancer?
There are a number of factors that might suggest that a person has a hereditary risk of breast or ovarian cancer. These include the presence of:
- breast and ovarian cancer on the same side of the family
- multiple cases of breast and/or ovarian cancer on the same side of the family
- early age at diagnosis (particularly breast cancer)
- male breast cancer
- bilateral breast cancer (cancer in both breasts)
- Ashkenazi Jewish ancestry
Q: What are the indicators of hereditary colon cancer?
The following characteristics may indicate that a person has a predisposition
for a particular type of colon cancer known as hereditary nonpolyposis colon
- multiple cases of colon cancer in successive generations
- early onset colon cancer
- right-sided colon cancers
- presence of other HNPCC-associated cancers (endometrial, ovarian, stomach, urinary tract)
Q: I’ve heard that before having genetic testing that it’s a good idea to meet with a genetic counselor. What is genetic counseling?
Deciding to pursue genetic testing can be a personal decision. By meeting with
a genetic counselor, patients and their families have an opportunity to consider
all the aspects of genetic testing. This can include information about the inheritance
of cancer genes, the medical facts of a particular type of cancer, the risk
of cancer associated with a particular gene, and all the available options.
A meeting with a genetic counselor provides:
- a detailed family history and risk factor assessment
- counseling about the pros/cons of testing
- a review of possible cancer management strategies
- information about cancer screening guidelines and preventive options
- emotional and psychosocial support
If the decision is made to proceed with genetic testing, the individual gives
his or her written consent before a blood test is done. Results are usually
available within 3-4 weeks. The genetic counselor then meets with the patient
to discuss the results and its implications.
Q: What is the cost of genetic testing?
The cost can range from about $300 to $3,000, depending on the type of test being performed.
Q: Is genetic testing usually covered by health insurance?
More and more insurance companies are covering genetic testing for cancer susceptibility genes. A genetic counselor can help determine what type of coverage you may expect to receive.
Q: How do I find out if I should have genetic testing?
If you are concerned that your personal or family history of cancer may be hereditary, our staff is available to provide guidance and counseling on risk factors and available genetic testing options. For more information or to make an appointment to speak with a genetic counselor, please call 410-328-2294 or 410-328-7855.