What is Cancer Genetic Testing?


Patient Education

What is Cancer Genetic Testing?

Genetic testing is the use of medical tests to look for certain mutations (changes) in a person’s genes. The results of a genetic test can tell you if you have a higher risk of developing specific diseases, such as cancer. Results of the genetic test may also guide your doctor in how your cancer is treated.  Doctors may recommend genetic testing for people who have certain types of cancers or those who have a family history of certain cancers.

Genetic testing is a complex process and the results of a test can be hard to interpret. A medical professional can help you understand the risks and benefits of genetic testing and interpret the results of your test.

Genetic Testing For Cancer Risk

Knowing your cancer risks can help you take steps to lower your chances of developing the disease. For some people, that knowledge comes from family history. If several relatives have been diagnosed with cancer, it may be worth doing cancer testing to see if you have a higher-than-average risk.

Most genetic tests for cancer are done using a blood or saliva sample performed at a medical clinic or at home.

At-Home Cancer Genetic Tests

In recent years, the availability of at-home genetic testing kits has increased dramatically. Individuals have the opportunity to learn about their genetic heritage and health risks with a simple saliva sample. Advances in genetic testing have made it possible to test for cancer at home using simple kits. These kits work by analysing a person's DNA for abnormalities that are associated with cancer.

While at-home cancer tests are not yet fully accurate, they represent a major step forward in the fight against this disease and may potentially save lives. Overall, there are pros and cons to home cancer genetic test kits, and more research is needed to determine their role in healthcare.

They can be ordered online or over the counter, and the results are typically available within a few weeks. In addition, home cancer genetic test kits provide people with a sense of control over their health. They can choose to take the test in the privacy of their own home, and they don’t have to wait for an appointment with a doctor.

However, the major downside of home cancer genetic test kits is the lack of accuracy. False positives can lead to unnecessary anxiety, and false negatives can give people a false sense of security. Home cancer genetic test kits are also not well regulated, and so there is no guarantee that they will meet certain standards of quality. Regardless of the outcome, you can always talk to your doctor about the test and the result.

Professionally Administered Cancer Tests

While home cancer genetic test kits are convenient and inexpensive, they do have limitations because they’re not as comprehensive or accurate as professionally administered cancer risk tests done in a clinic.

Before embarking on genetic testing, your doctor will usually assess your cancer risk and advise if genetic testing is right for you. They will also ensure that the correct genetic tests are ordered and the results are interpreted correctly.

The results of the genetic test can help your doctor come up with a personalized plan. For example, women at a higher risk of breast cancer due to a defect (mutation) in the BRCA gene may opt to undergo more frequent breast cancer screening to detect pre-cancer or early cancer. These women may also consider preventative measures, such as oral medications or even surgery, to reduce their cancer risks. These measures in turn help to save lives. For those already diagnosed with cancer, knowing if your cancer is hereditary in nature, may help your doctor fine-tune your cancer treatment, as certain hereditary cancers may respond better to particular types of anti-cancer drugs. For example, hereditary breast or ovary cancer due to a defective BRCA gene, responds well to a type of anti-cancer drug called the PARP inhibitor. Hereditary colon or womb (uterine) cancer respond exceptionally well to immunotherapy drugs.

Keep in mind that no genetic test can say if you will develop cancer for sure as there are many other factors besides your genes that determine your risk – age, diet, lifestyle all part a part. But it can tell you if you have a higher risk than most people.

For peace of mind and accuracy, get professionally administered cancer and genetic testing at OncoCare Cancer Centre in Singapore. Our experienced doctors and clinical staff provide screening and treatment options according to your individual preferences and requirements, with a focus on patient care. Schedule a genetic screening or cancer testing consultation today at one of our conveniently located clinics.

“Expert knowledge means better care for cancer”

Written by:
Dr Lim Sheow Lei
MBBS (Australia, Honours)
MRCP (United Kingdom)
MD (United Kingdom)