About the Test
Purpose of the test
The purpose of at-home colorectal cancer testing is to look for signs of cancer in people who do not have any symptoms. This is known as screening.
The goal of colorectal cancer screening is to find abnormal growths before they can become cancer or to find cancer at an earlier point when it is easier to treat. Cancer in the colon or rectum usually starts as an abnormal growth called a polyp. Screening tests are designed to detect bleeding that can not be seen visually and may indicate the presence of a polyp.
At-home tests are one type of colorectal cancer screening. Other types of screening tests can only be performed by a health care provider in a medical setting like a hospital or doctor’s office.
Several factors affect which type of screening test is most appropriate for a specific person, so it is important to talk with a doctor about the best option for you.
Purpose of an at-home colon cancer test
Some at-home colorectal cancer tests detect blood while others detect certain DNA biomarkers in a person’s stool.
Polyps that are cancerous or may become cancer often cause the release of trace blood or abnormal DNA into the stool. At-home tests can check the stool to see whether these are present.
At-home colorectal cancer tests allow for a stool sample to be collected at home and sent to a laboratory where it can be analyzed. Some self-test kits are also able to check for signs of blood in the stool at home without sending the sample to a laboratory.
In many cases, at-home colorectal cancer testing is prescribed by a doctor and the test kit is sent by mail. Often the doctor can prescribe the test without an in-person appointment. Test kits can also be purchased online or in many pharmacies without a prescription.
It is important for patients to share any results from at-home tests with their doctor. In addition, colorectal cancer screening tests are intended to be repeated periodically. A doctor can describe the recommended schedule for ongoing screening.
Purpose of a physician-ordered colon cancer test
The purpose of a physician-ordered colorectal cancer screening test is to check for indications of abnormal growths in the colon that are cancerous or could become cancer.
There are several different options for colorectal cancer screening that a doctor can prescribe. Screening tests are available that provide visual images of the colon and rectum must be performed by health care professionals. These tests can more effectively detect polyps that at-home tests and can only be performed in a medical setting.
Options for colorectal cancer screening ordered by a doctor and conducted in a medical setting include:
- Colonoscopy: This test uses a flexible tube with a camera to look at the inside of the colon and rectum and a tool that can be used to remove tissue (polyps). Air is pumped into the colon to expand it and make the lining more visible. The colon must be fully cleansed before the test.
- Virtual colonoscopy: This test uses computed tomography (CT) to take multiple x-rays and create a detailed image of the inside of the colon and rectum. While less invasive, it still requires a full cleansing of the colon. Virtual colonoscopy may not always detect small polyps.
- Sigmoidoscopy: This test is similar to a colonoscopy but only provides images of the rectum and lower third of the colon. Though less invasive and requiring less bowel preparation, less information is collected about the health of the full colon.
Each type of colorectal cancer screening test has benefits and drawbacks. For example, a colonoscopy is the most accurate at finding polyps, but it is also the most invasive. For this reason, a colonoscopy does not need to be repeated as frequently as other types of screening if no abnormalities are initially found.
No single screening test is the best for everyone. An advantage of physician-ordered colorectal cancer screening is that doctors and patients can discuss the pros and cons of testing options to determine the preferred choice based on a patient’s risk level and preferences.
What does the test measure?
At-home colorectal cancer tests detect blood that may be due to the presence of polyps in the colon or rectum. Each type of at-home test involves self-collecting a stool sample and testing as described in the following sections.
Fecal occult blood test
A fecal occult blood test (FOBT) measures whether there are microscopic traces of hemoglobin in the stool. Hemoglobin is a protein found in blood.
This test works by applying a small amount of stool to a test card that includes a chemical called guaiac. When analyzed in the laboratory, the guaiac changes color if the stool contains hemoglobin. For this reason, the test may also be called a guaiac FOBT or gFOBT.
In most cases, an FOBT includes three test cards that are meant to be used with three consecutive bowel movements. Depending on the test manufacturer, an FOBT may require temporary dietary changes before testing, such as avoiding red meat or high doses of vitamin C, to improve accuracy of the test measurement.
Fecal immunochemical test
A fecal immunochemical test (FIT) can detect blood in the stool by measuring the presence of antibodies to the hemoglobin, a protein that is found in blood. FIT is considered to be better at detecting blood than FOBT. FIT is performed on a sample from one bowel movement and does not require any changes to diet before the test.
A FIT-DNA test, also known as a multitarget stool DNA test, includes two measurements:
- Blood in the stool: The FIT-DNA test uses the same method as the FIT to look for evidence of blood in the stool.
- Abnormal DNA: The FIT-DNA test also checks the stool for DNA from the cells inside the lining of the colon and rectum. Abnormal DNA or genetic mutations from these cells can be a sign of colorectal cancer.
A FIT-DNA test requires the collection of an entire bowel movement that is sent to a laboratory for analysis. The test does not require any changes to diet beforehand.
When should I get an at-home colon cancer test?
At-home colorectal cancer tests are a form of screening, which means that they are intended for patients who do not have any symptoms of colon or rectal cancer.
Expert groups now recommend that all adults have colorectal cancer screening beginning at age 45 and continue until at least age 75. At-home screening tests should be repeated at specific intervals depending on the type of test used:
- FOBT or FIT tests should be repeated every year
- FIT-DNA tests should be repeated every 1 to 3 years
People who have a higher risk of developing colorectal cancer may be advised to start screening at a younger age, have screening tests more frequently, and/or have screening with a colonoscopy. Risk factors for colorectal cancer including having:
- A family history of colorectal cancer
- A personal history of concerning polyps
- An inherited condition such as Lynch syndrome or familial adenomatous polyposis
- An inflammatory bowel disease such ulcerative colitis or Crohn’s disease
- A history of cigarette smoking, excess alcohol use, or obesity
You should talk with your doctor about your risk for colon and rectal cancer and the best plan for screening in your situation, including whether you should use at-home tests.
At-home colorectal cancer tests are not appropriate if you have gastrointestinal symptoms such as visible blood in the stool, persistent abdominal pain, or a change in bowel habits. If you have any of these issues, you should talk with your doctor.
Benefits and Downsides of At-Home Colon Cancer Testing
At-home colorectal cancer testing offers certain benefits and drawbacks that are important to consider when deciding if this type of screening is right for you.
Potential benefits of at-home colorectal cancer testing include:
- Convenience: You can take the test from home at a time that fits your schedule without having to make an appointment or travel to a medical office.
- Noninvasive testing: At-home testing does not require any invasive procedure and does not cause any discomfort or side effects.
- Multiple options: Because there are several types of at-home stool tests, you can choose from different options based on your preferences, price, and recommendations from your doctor.
- Effective cancer screening: When performed regularly, at-home stool tests are considered by medical experts to be a dependable method of early detection of colorectal cancer for those who are at average risk for colorectal cancer.
- Supports working with your doctor: At-home tests can help advance conversations with your doctor about your risk of colorectal cancer. In many cases your doctor can order a test kit to be sent to your home.
Some of the potential downsides of at-home colorectal cancer screening include:
- Unpleasant sample collection: Some people may find the process of collecting a stool sample to be unpleasant. For some types of at-home tests, you are required to obtain a sample from three consecutive bowel movements or to collect an entire bowel movement.
- Repeat testing: At-home stool tests need to be repeated about every year, so it is necessary to perform the test much more often than some other types of colorectal cancer screening.
- May need follow-up tests: If an at-home test is abnormal, then follow-up testing is necessary, almost always with a colonoscopy.
- Detects fewer polyps: At-home tests do not detect polyps as well as a colonoscopy, so people who have a higher risk of developing colon and rectal cancer may be advised to be screened with a colonoscopy instead of stool-based tests.
- Possible dietary restrictions: For a FOBT at-home test, you may need to restrict your diet to avoid red meat and limit vitamin C intake for a few days before the test.
Your doctor can review these pros and cons with you to help decide which type of screening is best for you.
Types of At-Home Colon Cancer Tests
Three types of at-home colorectal cancer tests are available. Each involves self-collection of a stool sample, but there are important differences in how the sample is prepared and how the testing is carried out.
Fecal occult blood tests (FOBTs) and fecal immunochemical tests (FITs) can be obtained with or without a prescription. FIT-DNA tests are only available with a prescription.
Instructions for properly preparing for and taking the test can vary based on the type of test and the manufacturer, so it is important to look closely at the specific directions and materials included in any test kit.
Below you can find information about several of the best at-home colorectal cancer tests that are currently available.
Labcorp OnDemand Colorectal Cancer At-Home Test
Tests for: Blood in stool
Results timeline: Within about 2 days after sample is received by lab
The Labcorp OnDemand Colorectal Cancer At-Home Test uses fecal immunochemical testing (FIT) to detect blood in the stool. This technique can help find signs of polyps and colorectal cancer.
After you place an order, Labcorp OnDemand will send a full test kit directly to your home. The kit includes detailed instructions and all the materials needed to collect your test sample.
You can take the test when you are having a normal bowel movement. Place a collection paper into your toilet to catch your stool specimen. Remove the small collection wand from inside the plastic tube included in the test kit. Scrape your stool with the wand to collect a tiny sample and place the collection wand back into the tube. Package your sample in the included mailer and send it to the laboratory.
Once the CAP-accredited, CLIA-certified lab receives your sample, it will conduct the FIT to check for blood in the stool. Results are usually available within two days after your sample arrives.
You can access your test result through a secure website, and you may also receive a follow-up call or email if needed.
Free shipping is included both ways, and the test can be paid for by many HSA and FSA plans.
Since the test checks for blood, it’s important to wait to take it if you have blood in your stool from hemorrhoids or blood in your urine. These symptoms should be discussed with your physician. You should also wait to take the test if you just started your menstrual cycle.
Best Prescription-Only Option
Price: Varies based on insurance
Sample: Full stool sample
Tests for: Blood in stool and abnormal DNA
Results timeline: Within 14 days after mailing your sample
Cologuard is an at-home FIT-DNA test that can detect both blood in the stool and abnormal DNA that can come from colon polyps. It is a widely accepted, FDA-approved method of colorectal cancer screening.
Cologuard is only available with a prescription. Your primary care provider can order the test, and you can also work with a telemedicine provider who can help prescribe the test if you meet the criteria for colorectal cancer screening.
Once the test is prescribed, Cologuard ships you a box containing all the materials you need to prepare your sample. The kit includes a container and brackets to place it properly in your toilet. You will need to collect a full bowel movement while avoiding urine or putting any toilet paper in the container.
After you’ve finished going to the bathroom, use the enclosed device to scrape up a small sample of stool and place that device in the provided tube. Add the liquid from the test kit to the container and close it securely. Seal the container and tube in a plastic bag, then put the bag into the prelabeled box and ship the test back to the lab.
The Cologuard test includes an FIT analysis that checks your stool for traces of blood. It also analyzes your sample for any abnormal DNA that could come from colorectal polyps. Results are available within two weeks and are usually sent directly to your health care provider.
Cologuard is available for free or at a low cost for most people with health insurance in the United States, but the exact amount that you will pay depends on your insurance plan.
There are no required pretest preparations for the Cologuard test, but you should wait to take this test if you are on your period, have recently noticed blood in your stool or urine, or have hemorrhoids.
Best for FSA/HSA Payments
LetsGetChecked – Colon Cancer Screening Test
Price: $89 (Get 25% off with your exclusive Testing.com discount code. Use code TESTING25 at checkout.)
Tests for: Blood in stool
Results timeline: Within 2 to 5 days after sample arrives at lab
The LetsGetChecked Colon Cancer Screening Test is an FIT that provides a straightforward way to conduct colorectal cancer screening. Since LetsGetChecked accepts FSA and HSA payments directly through their website, this test is our pick for the best choice for people looking to use these accounts to pay for testing.
LetsGetChecked offers free shipping to send the test kit to your home. The kit has all the information and materials needed to collect a sample and send it back to their CAP-accredited, CLIA-certified lab with a prepaid return shipping label.
Please contact UPS to arrange a pickup before you collect your sample. You should collect your sample on the same day as the pickup is scheduled for. Visit the UPS pickup scheduling page or call 1-800-742-5877 to schedule a pickup to return your sample. You’ll be asked to provide some information including your tracking number, pickup address and pickup day and time. Please keep your tracking number to help you track your package.
To collect a sample, place a piece of collection paper into your toilet when you anticipate having a bowel movement. Defecate into the toilet and onto that paper. Then remove the collection wand from the kit’s small tube and use it to lightly scrape your stool.
Once you have a small sample of stool on the collection wand, put it back into the tube. Place the sealed tube into a biohazard bag, then seal and package the sample for shipping.
When the sample arrives at the lab, a fecal immunochemical test is performed to look for any indications of blood in your stool sample. The results are accessible within 5 days on a secure online account with the ability to see the test report on your smartphone. LetsGetChecked has a team of nurses you can contact with questions before, during, or after taking your test.
There are no special precautions or dietary changes required before taking the LetsGetChecked Colon Cancer Screening Test, but you should not take the test if you have blood in your stool or urine or if you are on your period.
Best for People Over 45
Everlywell – FIT Colon Cancer Screening Test
Sample: Stool swab
Tests for: Blood in stool
Results timeline: Within 5 days after sample arrives at the lab
The Everlywell FIT Colon Cancer Screening Test is an at-home test that lets you quickly obtain a stool sample that can be sent to a laboratory for testing.
This fecal immunochemical test (FIT) checks for signs of blood in the stool that can’t be seen by the naked eye. The test kit includes a special test card, two long-handled brushes to help obtain your sample, and a waste bag.
To take the test at-home, flush the toilet and then have a normal bowel movement. All used toilet paper should be placed in the waste bag instead of into the toilet. Use the brushes to obtain small samples of stool and apply them to the test card. Then seal and ship your test card to the lab.
Everlywell offers this test as a form of colorectal cancer screening, and it is only available to people who are over age 45. Results are provided within five days after the laboratory receives your sample. You can access your results through the company’s smartphone app, but the test report is also printable, making it easier to share with your doctor.
The cost of the test includes free shipping both ways, and Everlywell accepts HSA and FSA payments. Both written and video instructions are available to help you properly collect your test sample.
As with other FITs, you do not need to change your diet or medications before taking this test. However, if you have recently had hemorrhoids, blood in your urine, or started your menstrual cycle, you should wait before taking it.
Pinnacle BioLabs Second Generation FIT® test
Tests for: Blood in stool
Results timeline: Within 7 minutes
Because it’s a self-test, meaning you can collect the sample and conduct the analysis at home without sending anything to a lab, the Pinnacle BioLabs Second Generation FIT offers the fastest results of our top picks.
The test kit contains all of the materials needed to carry out the self-test and see if there is blood in your stool.
After placing a collection paper in the toilet, go to the bathroom normally and allow your stool to fall onto the paper. Then use a collection wand to scrape the stool and collect a very small sample. Place the collection wand in the provided tube, which contains a small amount of a chemical reagent. Shake the tube several times, and then place three drops from the tube onto the test cassette.
After 4 to 7 minutes, the results should be available. You can tell whether the test is positive or negative by looking at the test cassette and seeing how many lines are visible. Make sure to check for results no later than seven minutes after taking the test. Any results after this time period may not be valid.
Pinnacle BioLabs manufactures every test kit in the US, and the company will ship the kit to your home for free.
As with the other tests on our list, you should wait to conduct the test if you have recently had hemorrhoids or any other health issue that might cause blood in your stool. You should also wait if you have started your menstrual cycle or have recently had blood in your urine.
Interpreting At-Home Colon Cancer Test Results
The results of an at-home colorectal cancer screening test will typically be listed as either positive or negative.
- A positive result on an FOBT or FIT test means that traces of blood were detected in your stool. A positive result on a FIT-DNA test means that blood and/or abnormal DNA were found.
- A negative result means that no blood or abnormal DNA were detected.
A positive test result does not mean that you have cancer. No at-home test alone can determine whether you have colorectal cancer.
If your at-home test is positive, it means that you may have a polyp that is cancerous or could become cancer. However, other things besides cancer can cause a positive result. For this reason, you will need follow-up testing to determine the underlying cause of the abnormal test finding. Most often, a colonoscopy is performed for follow-up.
If your at-home test is negative, it means that there were no signs of polyps in your colon or rectum that are at risk of developing into cancer at this time.
A doctor is in the best position to interpret an at-home colorectal cancer test. They can discuss your risk factors for colorectal cancer, the findings of your test, and any recommended follow-up tests or future screening.
Are test results accurate?
At-home tests can be an effective form of colorectal cancer screening, but these tests are not able to detect all polyps or cases of colorectal cancer.
Stool tests cannot accurately detect polyps as well as a colonoscopy. This means that the test may be negative when a person actually has an abnormal polyp. This is known as a false negative result.
Because at-home stool tests do not detect as many polyps, they are only effective for colorectal screening when they are repeated at regular intervals. Many experts recommend that these tests be performed about every year.
It is also possible for an at-home test to have a positive result in someone who does not have an abnormal polyp. This is called a false positive result. For example, blood may be found in the stool of people with hemorrhoids and other conditions that are not cancer. As a result, follow-up tests are always needed after an abnormal at-home test to determine the cause.
Do I need follow-up tests?
Follow-up testing is needed if an at-home colorectal cancer test is positive. The most common type of follow-up test is a colonoscopy. During a colonoscopy, polyps can be removed for further analysis. Analyzing a sample of tissue from a polyp is the only way to determine if the polyp is cancerous.
A repeat at-home test may be necessary if your test sample was deemed inadequate. This may occur if there was a problem in how the test kit was prepared or if an insufficient sample was provided.
It is important to talk with a health care provider about any specific at-home test result and what kind of follow-up testing is most appropriate.
Questions for your doctor after at-home colon cancer testing
The following questions may be helpful when talking with your doctor about the results of your at-home colorectal cancer screening test:
- What was the result of my at-home test?
- Do you recommend any follow-up testing?
- How often should I be screened for colorectal cancer?
- Should I take another at-home test in the future?
- Is there anything that I can do to reduce my risk of colorectal cancer?
At-home colon cancer testing vs. colon cancer testing in a medical setting
A key difference between at-home colorectal cancer tests and screening conducted in a medical setting is the types of testing available.
Stool-based tests are the only kinds of tests that can be taken at home. In a medical setting, tests like a colonoscopy, virtual colonoscopy, or sigmoidoscopy can be used to generate and analyze images of the inside of the colon and rectum. A sample of tissue from a polyp can also be taken during a colonoscopy or sigmoidoscopy.
A standard colonoscopy is widely regarded as the most accurate way of finding polyps that are cancerous or could develop into cancer. However, it is more invasive and requires bowel preparation, which may mean taking laxatives and avoiding solid foods for a few days before the test.
At-home tests are typically more convenient. But because they are not as effective at detecting polyps, they need to be repeated more frequently than a colonoscopy. For most people, stool-based tests are done about every year, while a colonoscopy is recommended once every ten years.
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