Precision Colon Cancer Gene Testing
Approximately 5% of all colon cancer cases develop the disease due to genetic factors, which result from inheriting a faulty gene from either the mother or father. Currently, the two most common forms of genetically inherited colorectal cancer are familial adenomatous polyposis (FAP) and hereditary nonpolyposis colorectal cancer (HNPCC).
- Familial adenomatous polyposis (FAP), accounting for around 0.5–1% of colon cancer cases, is usually caused by a mutation on the APC tumor suppressor gene. This leads to colon polyps forming during the teenage years, of which more than 99% develop into colorectal cancer before the patient reaches the age of 40.
- Hereditary nonpolyposis colorectal cancer (HNPCC), or Lynch syndrome, is like FAP in that it is an inherited genetic disease. However, HNPCC is more common than FAP, responsible for 3–5% of all colon cancers. The disease comes about due to issues with the MLH1, MSH1, MSH6 and PMS2 genes, which are responsible for screening for genes that have undergone mutation. Normally, this condition can lead to an 80% increased lifelong risk of developing colon cancer, although the average age at which the cancer forms is between 40–50 years. Moreover, Lynch syndrome also increases the risk of developing various other forms of cancer, including cancer of the uterus, stomach, small intestine, pancreas, kidney, and urinary tract.
The role of precision medicine using genetics in preventing and diagnosing colon cancer
As a leader in Precision Medicine, Samitivej Hospital currently provides state-of-the-art genetic testing, using advanced technology that allows you to be proactive in your healthcare by screening for genetic abnormalities in the body. This screening method has detection accuracy rates of up to 90% and is used to test for a wide range of cancers. It is beneficial for:
- Cancer patients who wish to know of any abnormal genes that may pass increased cancer risk to their offspring. These test results can also be used to help create a specific, targeted treatment plan.
- Direct relatives of cancer patients who wish to know of any abnormal genes that they may have inherited from their parents in order to take preventive measures. The age range for direct relatives suitable for screening is as follows:
- First-degree relatives aged 12 years or older in a family with a history of FAP cancer
- First-degree relatives aged 20 years or older in a family with a history of HNPCC cancer
- Healthy persons aged 20 years and older who wish to know of any abnormal genes that they may have inherited from their parents in order to take preventive measures for the future.
If you are interested in having a genetic test for colon cancer, you can receive the service without having to fast. A nurse will collect your blood for the lab test. Results will be available within 2-4 weeks, at which time you will meet to have your test results explained by your doctor.