Colorectal cancer occurs usually in people aged 50 years or more. Both men and women can get colorectal cancer. Stool test is used to detect the signs of colorectal cancer. It checks for traces of blood that cannot be easily seen by a naked eye. The test should be repeated every year after the age of 50 to prevent the occurrence of colorectal cancer. Most people find a stool test to be easier than other tests, as it is non-invasive and can be easily done at home.
Fecal Occult Blood Test (FOBT)
The fecal occult blood test is done to detect occult (or hidden) blood in stools. Occult blood is the one that is not easily noticed by the naked eye. FOBT is a non-invasive and low-cost test that provides details about the exact quantity of blood in a stool sample. Generally, this test requires the collection of three consecutive stool samples because cancer may not bleed consistently. The FOBT uses the chemical guaiac to detect blood in your stool or faeces.
1. How it is Done?:
The fecal occult blood test can be easily done at your home. You will receive a kit along with the directions that will indicate how to take a stool sample. The stool sample is collected in a container and smeared into small squares of paper provided in the kit. The paper has a thin coating of the chemical guaiac. Once the testing is completed, the kit is returned to the doctor.
Some medications and drugs can interfere with this test.
- Nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, naproxen, and ibuprofen should be avoided for seven days before testing because they can cause bleeding and produce false results.
- Red meats should not be consumed for three days before testing, as the blood in the meat can make the test positive.
- The excessive consumption of vitamin C (250gm) should be avoided for three days before testing. This is because vitamin C can affect the chemical used in testing and gives negative results even when blood is present in stools.
Result is positive if microscopic blood is found in stools. Colonoscopy will be required to find the root cause of rectal bleeding.
Fecal Immunochemical Test (FIT)
The fecal immunochemical test uses antibodies to detect occult (hidden) blood in your stool. The procedure to conduct this test is same as the FOBT. Most people prefer this test over FOBT, since it is easier to do. You need to test multiple stools to ensure accuracy in the test, because many cancers don’t bleed regularly.
1. How it is Done?:
The kit will have all the supplies needed for conducting the test, such as long brushes, test kit, cards, waste bags, and mailing envelope. The instructions provided in the kit should be followed closely to have accurate results.
You first need to flush the toilet before passing your bowel movement. After you have passed the stools, brush the surface of your stool with a brush for several seconds. Shake the brush to remove* the bigger fecal particles and excessive water. Apply the end of the brush on the indicated spot of the test card. Dispose the brush when you have completed the testing. Don’t forget to write your name and date on the card. You may need to repeat the test two more time on the days as instructed by your doctor. Once all the tests are done, seal the envelope and return it to your doctor.
There are no diet and drug restrictions since food, drugs, and supplements do not interfere with the test results of FIT.
The presence of blood in stools indicates that result is positive. In such case, colonoscopoy is needed for further investigation.
Stool DNA Test (sDNA)
The cells of rectum and colon are shed in the stool. Stool DNA test detect abnormal DNA changes from polyp cells or cancer.
1. How it is Done?:
The stool DNA test kit will have all the instructions to conduct this test. The kit carries a container that fixes to the toilet. After the sample is collected, it is returned to the doctor. Only one sample is needed for this testing.
2. How to Prepare?:
There is not much preparation needed for stool DNA test. You can eat and drink normally before the test and continue your regular medicines. Also, there is no need to empty your colon.
A test is positive if DNA markers for pre-cancer and colorectal cancer are found in your stool sample. The patient needs to undergo additional colonoscopy for further investigation.
All types of stool tests are painless, easy to follow, and safe.
Stool test is a recommended screening test for people aged 50 years and above. Blood can be present in stools for many health conditions like haemorrhoids, anal fissures, peptic ulcers, and ulcerative colitis. However, if you are above the age of 50 and traces of blood are detected in your stools, you will need to undergo colonoscopy to check for polyps or colorectal cancer. Get yourself tested today. It could save your life!