At-Home Colon Cancer Tests vs Colonoscopy: What’s the Difference?
Colorectal cancer often develops quietly, and many people have no warning signs until the disease is more advanced. That’s what makes screening so important. When colorectal cancer is found early, treatment is often simpler, and outcomes are better. Colonoscopy screening can also stop cancer before it starts by finding and removing precancerous growths.
There are multiple options available to screen for this type of cancer. Some tests can be done at home while others are done in a medical office. Each has its benefits, limitations, and recommended uses. Understanding how the different types of testing compare can help you make an informed choice about what’s best for you.
Colorectal cancer screening falls into two general categories. One group of tests looks for signs of cancer in stool. The other looks directly inside the colon.
At-home stool tests check for hidden blood or abnormal DNA that may come from cancer or large polyps. The most common options include fecal immunochemical tests and stool DNA tests. These tests are done at home and mailed to a lab for results:
- Fecal Immunochemical Test (FIT) – This noninvasive test can detect small amounts of hidden blood in your stool by collecting a sample at home and shipping it directly to the lab. It is advantageous in that it is noninvasive and simple. However, detections of precancerous polyps are poor. FIT tests are typically done every year.
- Cologuard – This is a noninvasive screening option that is taken at home by collecting a stool sample and shipping it to the lab in specialized containers. This test looks for DNA in the stool, which are linked to colon cancers. The test does not detect precancerous polyps. Stool DNA tests are usually done every three years if results are normal.
The U.S. Preventive Services Task Force and most experts recommend screening beginning at age 45 if you’re at average risk. Average risk means no personal history of colorectal cancer or polyps, no strong family history, and no inflammatory bowel disease.
PIH Health Gastroenterologist Preeya Goyal MD says, “At home tests work for some people because they’re easy to do in the privacy of your home. There’s no bowel prep and no need to take time off work, but they can’t prevent cancer. They only look for signs that cancer or advanced polyps may already be present. A positive result always needs follow-up with a colonoscopy.”
A colonoscopy is an in-office procedure where a doctor uses a small camera to examine the entire colon and rectum. If polyps or abnormal tissue are found, they can usually be removed during the procedure.
Colonoscopy is the recommended colorectal cancer screening and is typically repeated every 10 years if nothing abnormal is found. It’s best for those with a family history of the disease, a personal history of polyps or certain genetic conditions. It’s also the next step after an abnormal at-home test.
Dr. Goyal also says, “While preparation to clean your colon is involved, a colonoscopy has a major advantage. It can find small polyps that may not be detected during at-home tests. And during your procedure, we can remove them, before they cause problems. Prevention is key.”
For some people, being able to do an at-home test means they’re more likely to get screened. For others, colonoscopy offers reassurance and longer-lasting protection, and the bottom line is that a preventive approach is preferred to help keep you healthy. Talk to your healthcare provider to decide which test is right for you.
To schedule a colonoscopy, call 562.967.2656 in Whittier; 562.904.4445 in Downey; or 213.977.4256 in Los Angeles. Visit PIHHealth.org/Colonoscopy to learn more.
