Genetics and Cancer Risk
Cancer Genetic Counseling is for individuals with cancer or individuals with a family history of cancer who are concerned about their personal risk for cancer, risk for a secondary cancer or risk for other family members. Many of us have either been affected by cancer personally or have friends or family members affected by cancer. There are many things that can put us at an increased risk to develop cancer. However research shows that up to 5-10% of all cancer has a hereditary component, which can run in the family. Individuals with or family member of individuals with a hereditary cancer have difference cancer risks. Fortunately, there have been many advances in recent years in the prevention, diagnosis, and treatment of cancer. Genetic testing is also available in order to test for some hereditary cancers.
Who is at risk for hereditary cancer?
Important points to consider in evaluating your family history for the possibility of hereditary cancer include:
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Cancer occurring at a younger age than the average in the general population. This usually means under age 50.
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The same type of cancer or related cancers in multiple blood relatives (example: breast and ovarian or colon and endometrial).
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Cancer occurring in both organs of a pair (example: both breasts).
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More than one occurrence of cancer in the same person.
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Cancer in two or more generations.
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Careful evaluation of your family history is the most important factor in determining a risk for hereditary cancer.
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In many cases a young age of onset is more significant than the number of people with cancer. Enlist the help of family members and try to get specific information. For example, "female cancer" could mean cancer of the cervix, uterus, or ovaries. When patterns of cancer are identified in a family, a hereditary form of cancer may be suspected.
What is cancer-related genetic testing?
Genes are the basic units of heredity. We all have approximately 30,000 genes in each of our cells. Some genes are involved in offers us some protection against cancer. If these genes have changes (mutations) in them that do not allow them to work correctly, this increases a person’s risk for developing cancer. Genetic testing looks at some of the genes that are known to cause an increased risk for cancer. The testing can identify individuals at increased risk for specific types of cancer who will benefit from increased cancer surveillance. A negative test result does not mean that a person well never develop cancer, but may indicate that the cancer risk is no higher than the risk in the general population. Testing is usually performed on a blood sample taken from a person’s arm or a small aliva sample. It is important that individuals interested in genetic testing carefully evaluate the benefits and limitations of the test and consider how the test results will impact their family. A genetic counselor can help with this.
How can genetic counseling help?
Genetic counseling can help assess your cancer risk and determine if you could benefit from genetic testing. An initial genetic consultation includes taking a detailed family history, assessing the risk for hereditary cancer, reviewing basic cancer genetics, and discussing options for surveillance and testing. Some people will be relieved to find out that the risk for cancer is lower than they anticipated. Other people who are at increased risk for cancer may choose to pursue genetic testing and feel empowered to make lifestyle and medical management decisions to lower their cancer risk or increase the chance for early detection and treatment.