It's no coincidence that you're seeing more information about genetic testing and how advances in the field are leading to a better understanding of your risk for certain diseases. While testing isn't perfect, it can be an important tool in knowing your risk and determining what steps you should take to detect cancer at an early stage. Below are some things you may want to know about genetic testing. For more information or to determine what testing may be right for you, please contact NHO to have an individualized discussion with one of our many trained providers.
What is DNA?
Deoxyribonucleic acid (DNA) is the instruction template that tells our body how to function, develop, and grow.
What is a gene?
A gene is a unit of DNA that provides the instructions for making proteins. These proteins may help the cells in our body communicate, control the chemical reactions in our body, and even make up our bodily tissues. Some genes (e.g. BRCA1 and BRCA2) contain instructions for proteins that protect our body from developing cancers in certain parts of our body.
What is genetic testing?
Genetic testing looks at DNA information in various genes to better understand and manage one’s healthcare. For most patients, genetic testing can be done on a blood or saliva sample. In the cancer setting, genetic testing may be recommended by your doctor to better assess and manage cancer risk or a cancer diagnosis.
Are DNA changes harmful?
Between each of us, there are approximately 3 million DNA changes, also called variants, which make us unique and give us differences in our hair color, height, and many other traits. Most of these changes are not harmful. In some instances, DNA changes in a gene may lead to abnormal protein production, these can be referred to as pathogenic variants or mutations. Pathogenic variants in genes which code for proteins responsible for protecting against the development of cancer can lead to hereditary cancer risk. For those with a strong family history of cancer or rare cancers, these pathogenic variants are what your doctor may recommend testing for to assess if you or your family have an increased risk to develop certain cancers.
Is all cancer genetic?
Yes, all cancer is genetic; cells acquiring abnormal DNA changes and growing uncontrollably. However, all cancer is not hereditary. For families with specific types of cancer (e.g. ovarian, pancreatic, or breast cancers), genetic testing can help in determining if cancers in the family are hereditary. Hereditary cancers typically present at younger ages, have multiple family members with the same or related types of cancer, and may present with multiple primary cancers in the same individual.
How common is hereditary cancer?
Most cancers are not hereditary. Overall, an estimated 5%-10% of cancer can be attributed to an inherited pathogenic variant. Sporadic cancers make up most cancers, followed by ‘familial’ cancers, which are attributed to shared lifestyle or environmental exposures within a family. Regardless of genetic testing status, everyone has some risk to develop cancer in their lifetime.
What does a negative result mean for me and my family?
A negative result does not eliminate the chance that cancer will develop in the family. For those with a strong family history of cancer, increased screening or surveillance may still be recommended. Genetic testing may be indicated for other family members and for you again in the future as testing advances and we better understand how our genes relate to our risk to develop cancer.
I have a positive result, what now?
Positive results may be associated with an increased risk for one, or multiple types of cancer. In response to an increased cancer risk, your healthcare providers can discuss ways to best manage your cancer risk. If a positive result is found in a family, genetic testing is strongly recommended to other family members. Identifying positive results can lead to risk reduction, earlier diagnosis, and better outcomes.
Nebraska Hematology Genetic Counselor Charlie King and a staff of highly-trained providers can assist patients through every step of the genetic testing and genetic counseling process. If you'd like to learn more or talk with someone about genetic testing, call our office at 402-484-4900.
Content for this article was provided by NHO Genetic Counselor Charlie King.