What Is Genetic Testing?
Genetic testing plays a major role in precision oncology. The information they provide is instrumental in selecting the best targeted therapies for your unique form of cancer. Genetic testing is sometimes also referred to as genomic testing, genetic screening, and diagnostic testing.
- Genetic tests:
- Detect changes (mutations) in the DNA of cancer cells
- Provide crucial information about what mutations are present in your genes
- Help your treatment team to select the best possible targeted therapy for you
- Can predict which treatments will benefit you the most
- Can predict which treatments your genes will not respond to
The importance of genetic testing cannot be underestimated. Knowing all of the genetic mutations involved in driving your cancer is the only way to know which targeted therapies will provide you with the most successful treatment outcome.
In order to choose the best targeted therapy, your treatment team must know:
- Which mutations are triggering your cancer
- Which mutations are supporting your cancer to proliferate
- How each mutation interacts with one another
Genetic testing provides all of this information, enabling us to choose the most effective treatment for you.
The interaction between gene mutations is complex. Problems with treatment plans can arise if your doctor doesn’t understand the interplay between the different gene mutations driving your cancer. For example, you need to know that a treatment targeting one genetic mutation will not have unintentionally adverse effects on other mutations.
- Consequence of NOT using genetic testing
Failing to consider the interplay between mutations has consequences. It can lead to choosing a treatment plan that targets one genetic mutation successfully while inadvertently causing increased growth in another gene mutation.
This is why successful targeted therapy regimes require genetic testing. Happily, medical science has developed a variety of genetic tests that detect mutations in cancer tissue. These genetic tests show whether a specific targeted therapy is likely to benefit a cancer patient.
Best Genetic Tests for Cancer
Typically speaking, these are the two main forms of genetic tests for cancer:
- Liquid Biopsy
A sample of your blood plasma is obtained through a simple blood draw, and that sample is then tested for a short list of common mutations.
- Turnaround time is fast, typically less than a week
- It can confirm whether certain common mutations are driving your cancer
- It can confirm whether the treatment you are on is right for you
- Also sometimes referred to as: Circulating tumour DNA test (ctDNA) or Cell free DNA test (cfDNA)
- A liquid biopsy is incredibly useful when your treatment team suspects a certain mutation is involved in your cancer – and wants to know for sure, as soon as possible.
- Genetic Panels
A slide of your tumour tissue (from a previous biopsy) is tested for a large panel of genetic mutations.
- Provides a far more detailed panel than a liquid biopsy test
- Shows us the key mutations involved in your cancer
- Presents options for targeted therapies
- Turnaround time is slower than a liquid biopsy, typically taking about 3 weeks, once the lab has received a sample of your tumour tissue
- CTOAM uses a Detailed Genetic Testing panel that looks at over 300 possible mutations. These mutations:
- Are known to influence the development of cancer
- Are considered targetable (i.e. there are specific treatments available that target those mutations directly)
- A Detailed Genetic Testing panel provides us with a very clear picture of the key mutations involved in driving your cancer. Significantly, it allows our cancer specialists to explore all possible targeted cancer therapy options available for you.