Some prostate cancer patients will need help understanding the complexity of genetic results, a new study finds.
As genetic testing for various diseases gains in popularity, researchers are finding that there can be confusion about what the test results really mean, how much they increase a person’s risk of disease, and whether there’s any important action to take. A recent report from the Genetic Evaluation of Men (GEM) study led by Sidney Kimmel Cancer Center (SKCC) at Jefferson Health researchers shows that while men who have inherited genetic mutations related to their prostate cancer are more likely to have a good understanding of general genetic test results, some men had confusion about a subcategory of genetic results – genetic variants of uncertain significance (VUS). The study was recently published in the journal The Prostate.
“This is another example of how important it is guide patients through their test results so that men and their families aren’t unduly worried when the risk is not great, and take appropriate action when there is a strong risk,” said first author and medical oncologist Veda Giri, MD, Director of the Jefferson Clinical Cancer Genetics Service and the Men’s Genetic Risk Clinic at SKCC.
Here’s a breakdown of the difference:
Genes provide a blueprint for the building blocks, or proteins, of a cell. Genetic mutations are changes in the genetic code that are associated with disease development or risk, such as cancer. When mutations related to prostate cancer are identified from genetic testing, a man – and members of his family – can have a higher risk of developing the disease and potentially other linked cancers.
Variants of uncertain significance (VUS) are changes in the DNA where the interpretation isn’t clear regarding their association to disease. These VUS are reported to patients in their genetic test results, and do not influence cancer risk or management recommendations at the time of reporting. VUS are tracked over time by genetic testing laboratories for evidence of association to cancer. Over time, VUS can be reclassified to “benign” or “mutation.” If a VUS is reclassified to “mutation,” there may be cancer risk and management implications for patients and their families.
In the GEM study, Giri and colleagues are performing genetic testing for men where results may identify mutations or VUS. Therefore, men need to understand the implications of these various types of genetic test results for appropriate cancer screening, cancer management, and familial discussions of genetic testing.
Their study showed that men can be confused about the difference between genetic mutations and genetic variations of uncertain significance, which may cause unnecessary anxiety and potential inappropriate management, pointing to the importance of discussing genetic testing and results with a trained healthcare professional or cancer genetic specialist.
“Genetic test results can be complex, and patients need expertise and support for understanding their results, such as through a genetic counselor or trained healthcare professional,” Giri said.
“The pace of breakthroughs in linking genetic alterations to cancer risk is intensifying. As such, the Sidney Kimmel Cancer Center has developed strategies to not only provide the most advanced testing, but to convey information about cancer risk through patient-centric exceptional genetic counseling,” said SKCC Director Karen E. Knudsen, PhD.
The study was completed in collaboration with researchers from the Fox Chase Cancer Center. Elias Obeid, MD, of Fox Chase, was co-first author on the paper.