PROSTATE PROS Episode 11: Applying Genetic Therapy

Listen: https://soundcloud.com/prostate-oncology/applying-genetic-therapy

“Someday in the future we may not define the cancers as prostate cancer, ovarian, or lung.  We might start to define the cancers based on the genetic abnormality that’s discovered with biopsies or blood testing.  The reason is that it opens the doorway to knowing what the right treatment is.”– Dr. Scholz

Genetic testing and genetically targeted therapy can be beneficial for men with prostate cancer. Genetic tests can tell us all sorts of information from how your prostate cancer may behave to if you are genetically predisposed to getting a future prostate cancer.  

How genetic tests are performed:

1. Mouth Swab 
2. Tissue tests (lymph node or biopsy tissue–you will not need another biopsy to have a genetic test performed)
3. Spots on bone
4. Blood tests

There are two main categories of application for genetic tests: genetic tests for newly diagnosed men and genetic tests for men with advanced prostate cancer. 

Genetic Testing for the Newly Diagnosed: 

For newly diagnosed men there are three tests: Prolaris, Decipher, and Oncotype.  These tests tell newly diagnosed men if their cancer is ok to be watched using modern active surveillance protocol or if their prostate cancer will require further treatment.  The results are reported as the percentage likelihood that the cancer will spread outside of the prostate.

Keep in mind that sometimes the finding of these tests don’t line up with the understanding your doctors have of your cancer based on accurate staging using your labs, PSA, Gleason Score, etc.  This can lend to confusion about the next steps to take. These tests benefit men with favorable Gleason 7 prostate cancer the most. Gleason 7 is a type of prostate cancer that bridges the gap between needing treatment and eligibility of active surveillance.  The genetic tests mentioned above can help indicate the best steps for these patients. 

Men in these categories should be aware that there is a one percent chance their genetic slides will be confused with someone else’s.  Luckily there is a test called know error® which is a cheek swab that will compare your genetic samples and make sure that your results are yours.  

Advanced Prostate Cancer: 

So, why are genetic tests typically reserved for men with advanced prostate cancer?  Well, right now the types of medicines available to treat the known genetic mutations all have potentially very significant side effects; therefore, it is really only people who have more serious prostate cancer who can justify taking them. 

For advanced prostate cancer the issue is connecting the mutation to a treatment.  Not all mutations have treatments, so sometimes knowing about genetic mutations can’t help guide treatment, but instead just provides (sometimes frightening) knowledge of a mutation of which there is no known treatment.  

Here are some examples of the genes these tests look for and the considered treatment if that gene is present: 

1. ATM and BRCA– The recommended treatments for men with these mutations are the ovarian cancer drugs Olaparib (Lynparza) or Rucaparib.
2. Microsatellite instability– This mutation is found in 1% of men but if found, KEYTRUDA works extremely well. 
3. Genes present in other types of cancers that have known treatments.
4. KRAS-variant–  This indicates how well a patient will respond to immunotherapy (ImuDx).   

Genetic testing for family history: 

Genetic testing has become increasingly popular over the last several years when direct-to-consumer genetic tests like 23andMe came on the market.  These tests can tell you about what genetic mutations you have. While a lot of genetic mutations are harmless, some do indicate a heightened risk for certain illnesses.  Finding out information about your DNA can come with a lot of anxiety and knowledge of which nothing can be done with. Before getting genetic testing in this capacity it may be smart to consult with a genetic professional called a genetic counselor.

For more on ImuDx listen to the Intelligence of Immunotherapy podcast episode: https://www.prostateoncology.com/2020/02/03/prostate-pros-episode-9-the-intelligence-of-immunotherapy/  

Watch the PCRI Mid-Year Update online: https://pcri.org/2020-midyear-update 

Have questions or topics you think would be great for PROSTATE PROS? Email podcast@prostateoncology.com

Subscribe, rate, and review on Apple Podcasts

Check out more episodes on podcast.prostateoncology.com 

Join the conversation, follow us on twitter: @keepprostate

The purpose of this podcast is to educate and inform.  The information presented on this podcast and corresponding blog posted on prostateoncology.com/blog should not be used in place of a physician consult. Guests on the podcasts present their own opinions and conclusions, these views do not necessarily represent that of Prostate Oncology Specialists.