Colorectal Cancer: Which Screening Test Should I Have?

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You may want to have a say in this decision, or you may simply want to follow your doctor's recommendation. Either way, this information will help you understand what your choices are so that you can talk to your doctor about them.

Colorectal Cancer: Which Screening Test Should I Have?

Get the facts

Your options

Key points to remember

  • All of the screening tests work well to lower your risk of getting and dying from colorectal cancer. No matter what test you choose, regular testing can find signs of cancer early, when the cancer may be easier to treat.
  • The tests differ in how they are done, how often they are done, and how you prepare for them. Your preferences are important in choosing what test to have. Think about what matters most to you as you look at what each test involves.
  • No matter which test you choose, it's important that you have the test on the recommended schedule and have any follow-up visits or tests as needed. That gives you the best chance of reducing the risk of dying from colorectal cancer.
  • Routine testing is recommended for everyone age 50 and older who has an average risk for colorectal cancer. Your doctor may recommend getting tested earlier or more often if you have a higher risk. If you are older than 75 or have serious health problems, you and your doctor might decide that it's best for you not to be screened.
FAQs

What is colorectal cancer?

Colorectal cancer happens when cells that are not normal grow in your colon or rectum. Most people just call it "colon cancer."

These cancers usually begin as polyps. Polyps are growths attached to the inside of the colon or rectum. Colon polyps are common. Most of them don't turn into cancer. Polyps are found during some screening tests. And polyps found during a colonoscopy usually can be removed at the same time.

Why is regular screening important?

Colorectal cancer is easier to treat when it is found early through screening tests.

With colorectal cancer, symptoms often don't show up until the cancer is advanced. So regular screening—no matter what test you choose—makes it more likely that cancer will be found early.

Why is your family history important?

A family history of colorectal cancer makes you more likely to get it. You may need to be screened at an earlier age—and be tested more often—than other people if:

  • You have a close relative with colorectal cancer. You are more likely to get colorectal cancer if:
    • One of your parents, brothers, sisters, or children had it before the age of 60.
    • Two or more of your parents, brothers, sisters, or children had it at any age.
  • You have a family history of certain colon problems. These include familial adenomatous polyposis (FAP) and hereditary nonpolyposis colon cancer (HNPCC). Most people who inherit these conditions will get colorectal cancer if they are not screened and treated.

What are stool tests?

Stool tests involve checking your stool for tiny amounts of blood or other signs of colorectal cancer.

Most stool tests need to be done once a year. These tests can usually be done in your home.

There are different types of stool tests:

  • Fecal immunochemical test (FIT). This test checks for signs of blood in the stool. The test kit contains the things that you need for collecting small samples of stool.
  • Fecal occult blood test (FOBT). This test also checks for signs of blood in the stool. The test kit contains the things that you need for collecting small samples of stool. With an FOBT, you will be given instructions about foods to avoid in the days before the test.
  • Stool DNA (sDNA/Cologuard). This test checks the stool for blood and genetic changes in DNA that could be signs of cancer. The test kit has a container for collecting an entire stool sample. This test is recommended every 3 years.

You can get an at-home stool test from your doctor or your local drugstore, or you can order one online. Your test kit will have instructions about how to do the test, including how to return your stool samples. Some tests provide the results right away. If your test shows a positive result (blood was found), call your doctor as soon as possible.

Risks of stool tests

There is no risk from the stool test itself. For this test, you put a sample of stool on a card or you collect a stool sample.

But there are some important things to think about. If your test is positive, you will need to have a colonoscopy. This would be used to see if the stool test result is from colorectal cancer. But blood in the stool is more often caused by something other than cancer. These other causes could include hemorrhoids, ulcers, or taking aspirin. A positive test result could lead you to worry. And you might have a colonoscopy that you didn't need.

What is colonoscopy?

Colonoscopy (say "koh-luh-NAW-skuh-pee") is a test that lets your doctor look at the inside of your entire colon. The doctor looks through a lighted tube that can bend around the corners of the colon.

With this test, the doctor can find and remove polyps, which are growths inside the colon that can turn into colorectal cancer.

When used as a screening test for colorectal cancer, this test is usually done every 10 years. If you have a colonoscopy, you won't need to have a yearly stool test. A colonoscopy may be done more often if your risk is higher than average.

Getting ready for a colonoscopy involves a very thorough cleansing of the colon. The colon must be completely empty.

  • For 1 to 2 days before the test, you will be on a clear liquid diet.
  • On the night before the test, your doctor may have you take a prescription laxative tablet or drink a large container of laxative solution. This will make you use the bathroom often.

During the test, you may be given medicine to help you relax. Many people don't remember the test afterward because they are so relaxed.

The test usually takes 30 to 45 minutes. But it may take longer if polyps are found and removed.

Risks of colonoscopy

There is a small risk of problems from having a colonoscopy. The scope or a small tool may tear the lining of the colon or cause bleeding. Although these problems are rare, they happen more often with colonoscopy than with sigmoidoscopy.footnote 1

What is sigmoidoscopy?

Sigmoidoscopy (say "sig-moy-DAW-skuh-pee") is a test that lets your doctor look at the inside of the lower part of your colon. The doctor looks through a lighted tube that can bend around the corners of the colon.

When used to screen for colorectal cancer, this test is usually done every 5 years. Most people who get this test also get a yearly stool test.

Getting ready for a sigmoidoscopy involves cleaning out the colon.

  • For 1 to 2 days before the test, you may be on a clear liquid diet.
  • You will likely have an enema before the test.

This test usually takes 5 to 15 minutes. It may take slightly longer if polyps are found and removed.

Risks of sigmoidoscopy

There is a small risk of problems from having a sigmoidoscopy.

There is a slight chance of piercing the colon (perforation) or causing severe bleeding by damaging the wall of the colon. But this is rare. There is also a very rare chance of a colon infection.

A sigmoidoscopy only looks at the lower part of your colon, which is where most polyps grow. But sometimes polyps grow in the upper part of your colon. Those polyps would not be seen with this test.

If your doctor finds polyps during a sigmoidoscopy, you will need to have a colonoscopy to see if there are more polyps farther up in your colon. And that test also has possible risks.

What is CT colonography?

CT colonography uses pictures taken during a CT scan to look at the colon. A thin tube is inserted into the rectum, and air is pumped through the tube into the colon. The air expands the colon so that it is easier to see on an X-ray.

This test is not done everywhere, so it may not be an option for many people. When used as a screening test, it is usually done every 5 years.

Getting ready for this test involves the same cleansing of the colon that is needed for a regular colonoscopy.

If anything is found during the CT scan, you may need to have more tests, such as a colonoscopy, to make sure that you don't have cancer.

Risks of CT colonography

There is a very small risk that the lining of the colon may be injured or torn when air is pumped into the colon. This may cause bleeding.

CT colonography may find things outside the colon that might never have caused a problem if they had not been found through screening. But this test can't tell whether the problem is harmless. So you may need more tests or treatment. This can cost a lot and cause worry.

You will be exposed to radiation during this test. There is a small chance of getting cancer from having repeated CT colonographies or other CT scans.footnote 2 The chance is higher in people who have many radiation tests.

What do experts recommend?

Experts recommend stool tests, sigmoidoscopy or sigmoidoscopy with stool tests, colonoscopy, or CT colonography to screen for colorectal cancer.

Recommendations from the U.S. Preventive Services Task Force

The USPSTF recommends that you have one of the screening tests on its suggested schedule.footnote 3 They don't recommend one test over another. Talk with your doctor to decide which test is right for you.

  • People ages 50 to 75 should have a screening test for colorectal cancer starting at age 50.
  • People ages 76 to 85 can choose whether to be screened.
  • People ages 86 and older should not be screened for colorectal cancer.

Recommendations from other groups

  • The American Cancer Society (ACS), the American Gastroenterological Association (AGA), and the American College of Gastroenterologists (ACG) recommend routine testing for people age 50 and older who have a normal risk for colorectal cancer.
  • Your doctor may recommend being tested earlier or more often if you have a higher risk for colorectal cancer. Talk to your doctor about when you should be tested.

Compare your options

Compare

What is usually involved?









What are the benefits?









What are the risks and side effects?









Stool test Stool test
  • You do the FIT or the FOBT test every year. Or you do the sDNA test every 3 years.
  • It's done at home.
  • You take samples of your stool. You may find out your results right away. Or you may need to mail the sample to a lab or your doctor's office to get the results.
  • Screening tests work well to lower your risk of getting and dying from colorectal cancer. For example, with the FIT stool test (over 30 years):
  • It's easy to do at home.
  • A stool test costs less than other tests.
  • You don't need to use laxatives or enemas.
  • A "positive" result means you will need a colonoscopy, which also has risks.
  • You may have a "positive" result from conditions that are not cancer, such as hemorrhoids or colon polyps. This could lead to worry and having a colonoscopy to make sure that you don't have cancer.
Colonoscopy or other procedures Colonoscopy or other procedures
  • You have one of the following procedures:
    • A colonoscopy every 10 years. It will likely be done more often if you have things that increase your risk for colorectal cancer or if polyps are found.
    • A sigmoidoscopy every 5 years, or every 10 years with the FIT stool test every year.
    • A CT colonography every 5 years.
  • These procedures are done in a doctor's office, clinic, or hospital.
  • You use laxatives to clean out your bowels.
  • With colonoscopy, you are given drugs to relax. You may not remember the test at all.
  • Screening tests work well to lower your risk of getting and dying from colorectal cancer. For example, with colonoscopy (over 30 years):
  • You don't have to do these tests as often as a stool test.
  • These procedures can find polyps before they turn into cancer. Polyps anywhere in the colon usually can be removed during a colonoscopy. During a sigmoidoscopy, a doctor may be able to remove polyps from the lower colon.
  • For all procedures
    • Bleeding problems and a tear in the colon are rare. But they are more common with colonoscopy than with sigmoidoscopy or CT colonography. With colonoscopy, this happens in less than 3 out of 1,000 people.footnote 4, footnote 5
    • These procedures cost more than stool tests.
  • For sigmoidoscopy
    • This test only sees the lower part of the colon.
    • There may be some discomfort during the test.
    • If polyps are found, you will need a colonoscopy to see if there are more polyps farther up in your colon.
  • For CT colonography
    • If polyps are seen during this test, you will need a colonoscopy.
    • There may be some discomfort during the test.
    • This test may show problems that are outside the colon. Then other tests or treatment may be needed.
    • You are exposed to some radiation.

Personal stories about test methods for colorectal cancer

These stories are based on information gathered from health professionals and consumers. They may be helpful as you make important health decisions.

No one in my family has ever had colon cancer. I try to eat a balanced diet and get plenty of exercise. I decided on FIT, since I've heard that doing this test yearly is just about as good as having a colonoscopy, but with fewer risks. And I don't have to do the bowel prep.

Patrick, age 56

I've had a fecal occult blood test every year for the past 4 years, and I'm going to continue with this test. My doctor gives me the kit every year and I know what foods to avoid, so it isn't a big deal.

Jose Luis, age 54

When I turned 50, my doctor recommended a yearly FIT with a sigmoidoscopy every 10 years. I'm okay with that. I live in a rural area and I'd have to travel quite a ways to have a colonoscopy. I'd rather have my medical care close to home.

Frank, age 52

I had a colonoscopy. I didn't care for the prep. I had to drink lots of fluid and stay close to the bathroom for the whole time. But the test itself was no big deal. They didn't find any polyps. I like knowing that I don't have to do this again for 10 years.

Stella, age 58

I chose the stool DNA test. My medical plan offers several options. I decided on the stool DNA test since I can do this one at home. My doctor said I'd need to do this test every 3 years. Now that I've done it once, I'm fine with that. The test was simple to do, and the directions were easy to follow.

Edna, age 55

What matters most to you?

Your personal feelings are just as important as the medical facts. Think about what matters most to you in this decision, and show how you feel about the following statements.

Reasons to have a stool test

Reasons to have a colonoscopy or other procedure

I'm afraid of a test that involves putting anything into my colon.

I'm not too worried about having a test that involves putting something into my colon.

More important
Equally important
More important

I'm okay with doing a test that only checks for signs of blood in my stool.

I want to have a test that is going to see as much as possible.

More important
Equally important
More important

It's important to me to do testing at home, in private.

I don't mind going to a clinic or hospital to have a colonoscopy or other procedure.

More important
Equally important
More important

I don't like the idea of drinking a lot of laxative solution (bowel prep) and spending a long time in the bathroom before a test.

I don't mind having to do the bowel prep before a test.

More important
Equally important
More important

I don't want to miss any work for this test.

I'm not worried about missing work to have this test.

More important
Equally important
More important

I'm willing to do a stool test every year.

I want to get the test over with and not think about it for another 10 years.

More important
Equally important
More important

I'm worried about the cost of having a colonoscopy or other procedure.

I'm not worried about the cost of having a procedure.

More important
Equally important
More important

My other important reasons:

My other important reasons:

More important
Equally important
More important

Where are you leaning now?

Now that you've thought about the facts and your feelings, you may have a general idea of where you stand on this decision. Show which way you are leaning right now.

Using a stool test

Having a colonoscopy or other procedure

Leaning toward
Undecided
Leaning toward

What else do you need to make your decision?

Check the facts

1, Will having regular screening tests lower your chances of dying from colorectal cancer?
2, Is colonoscopy a lot better at preventing deaths from cancer than the other screening tests?
3, Does having a stool test mean that I won't need to have a colonoscopy?
4, Will you have to do stool tests more often than you'll have to get a colonoscopy or other procedure?

Decide what's next

1,Do you understand the options available to you?
2,Are you clear about which benefits and side effects matter most to you?
3,Do you have enough support and advice from others to make a choice?

Certainty

1. How sure do you feel right now about your decision?

Not sure at all
Somewhat sure
Very sure

Your Summary

Here's a record of your answers. You can use it to talk with your doctor or loved ones about your decision.

Your decision 

Next steps

Which way you're leaning

How sure you are

Your comments

Your knowledge of the facts 

Key concepts that you understood

Key concepts that may need review

Getting ready to act 

Patient choices

Credits and References

Credits
AuthorHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Primary Medical ReviewerKathleen Romito, MD - Family Medicine
Specialist Medical ReviewerKenneth Bark, MD - General Surgery, Colon and Rectal Surgery

References
Citations
  1. Dinh T, et al. (2013). Health benefits and cost-effectiveness of a hybrid screening strategy for colorectal cancer. Clinical Gastroenterology and Hepatology, 11(9): 1158–1166. DOI: 10.1016/j.cgh.2013.03.013. Accessed January 13, 2015.
  2. Einstein AJ, et al. (2007). Estimating risk of cancer associated with radiation exposure from 64-slice computed tomography coronary angiography. JAMA, 298(3): 317–323.
  3. U.S. Preventive Services Task Force (2016). Screening for colorectal cancer: U.S. Preventive Services Task Force recommendation statement. JAMA, 315(23): 2564–2575. DOI:10.1001/jama.2016.5989. Accessed June 27, 2016.
  4. Warren JL, et al. (2009). Adverse events after outpatient colonoscopy in the Medicare population. Annals of Internal Medicine, 150(12): 849–857. DOI: 10.7326/0003-4819-150-12-200906160-00008. Accessed February 2, 2015.
  5. Rabeneck L, et al. (2008). Bleeding and perforation after outpatient colonoscopy and their risk factors in usual clinical practice. Gastroenterology, 135(6): 1899–1906. DOI 10.1053/j.gastro.2008.08.058. Accessed February 13, 2015.
You may want to have a say in this decision, or you may simply want to follow your doctor's recommendation. Either way, this information will help you understand what your choices are so that you can talk to your doctor about them.

Colorectal Cancer: Which Screening Test Should I Have?

Here's a record of your answers. You can use it to talk with your doctor or loved ones about your decision.
  1. Get the facts
  2. Compare your options
  3. What matters most to you?
  4. Where are you leaning now?
  5. What else do you need to make your decision?

1. Get the Facts

Your options

Key points to remember

  • All of the screening tests work well to lower your risk of getting and dying from colorectal cancer. No matter what test you choose, regular testing can find signs of cancer early, when the cancer may be easier to treat.
  • The tests differ in how they are done, how often they are done, and how you prepare for them. Your preferences are important in choosing what test to have. Think about what matters most to you as you look at what each test involves.
  • No matter which test you choose, it's important that you have the test on the recommended schedule and have any follow-up visits or tests as needed. That gives you the best chance of reducing the risk of dying from colorectal cancer.
  • Routine testing is recommended for everyone age 50 and older who has an average risk for colorectal cancer. Your doctor may recommend getting tested earlier or more often if you have a higher risk. If you are older than 75 or have serious health problems, you and your doctor might decide that it's best for you not to be screened.
FAQs

What is colorectal cancer?

Colorectal cancer happens when cells that are not normal grow in your colon or rectum . Most people just call it "colon cancer."

These cancers usually begin as polyps. Polyps are growths attached to the inside of the colon or rectum. Colon polyps are common. Most of them don't turn into cancer. Polyps are found during some screening tests. And polyps found during a colonoscopy usually can be removed at the same time.

Why is regular screening important?

Colorectal cancer is easier to treat when it is found early through screening tests.

With colorectal cancer, symptoms often don't show up until the cancer is advanced. So regular screening—no matter what test you choose—makes it more likely that cancer will be found early.

Why is your family history important?

A family history of colorectal cancer makes you more likely to get it. You may need to be screened at an earlier age—and be tested more often—than other people if:

  • You have a close relative with colorectal cancer. You are more likely to get colorectal cancer if:
    • One of your parents, brothers, sisters, or children had it before the age of 60.
    • Two or more of your parents, brothers, sisters, or children had it at any age.
  • You have a family history of certain colon problems. These include familial adenomatous polyposis (FAP) and hereditary nonpolyposis colon cancer (HNPCC). Most people who inherit these conditions will get colorectal cancer if they are not screened and treated.

What are stool tests?

Stool tests involve checking your stool for tiny amounts of blood or other signs of colorectal cancer.

Most stool tests need to be done once a year. These tests can usually be done in your home.

There are different types of stool tests:

  • Fecal immunochemical test (FIT). This test checks for signs of blood in the stool. The test kit contains the things that you need for collecting small samples of stool.
  • Fecal occult blood test (FOBT). This test also checks for signs of blood in the stool. The test kit contains the things that you need for collecting small samples of stool. With an FOBT, you will be given instructions about foods to avoid in the days before the test.
  • Stool DNA (sDNA/Cologuard). This test checks the stool for blood and genetic changes in DNA that could be signs of cancer. The test kit has a container for collecting an entire stool sample. This test is recommended every 3 years.

You can get an at-home stool test from your doctor or your local drugstore, or you can order one online. Your test kit will have instructions about how to do the test, including how to return your stool samples. Some tests provide the results right away. If your test shows a positive result (blood was found), call your doctor as soon as possible.

Risks of stool tests

There is no risk from the stool test itself. For this test, you put a sample of stool on a card or you collect a stool sample.

But there are some important things to think about. If your test is positive, you will need to have a colonoscopy. This would be used to see if the stool test result is from colorectal cancer. But blood in the stool is more often caused by something other than cancer. These other causes could include hemorrhoids, ulcers, or taking aspirin. A positive test result could lead you to worry. And you might have a colonoscopy that you didn't need.

What is colonoscopy?

Colonoscopy (say "koh-luh-NAW-skuh-pee") is a test that lets your doctor look at the inside of your entire colon . The doctor looks through a lighted tube that can bend around the corners of the colon.

With this test, the doctor can find and remove polyps, which are growths inside the colon that can turn into colorectal cancer.

When used as a screening test for colorectal cancer, this test is usually done every 10 years. If you have a colonoscopy, you won't need to have a yearly stool test. A colonoscopy may be done more often if your risk is higher than average.

Getting ready for a colonoscopy involves a very thorough cleansing of the colon. The colon must be completely empty.

  • For 1 to 2 days before the test, you will be on a clear liquid diet.
  • On the night before the test, your doctor may have you take a prescription laxative tablet or drink a large container of laxative solution. This will make you use the bathroom often.

During the test, you may be given medicine to help you relax. Many people don't remember the test afterward because they are so relaxed.

The test usually takes 30 to 45 minutes. But it may take longer if polyps are found and removed.

Risks of colonoscopy

There is a small risk of problems from having a colonoscopy. The scope or a small tool may tear the lining of the colon or cause bleeding. Although these problems are rare, they happen more often with colonoscopy than with sigmoidoscopy.1

What is sigmoidoscopy?

Sigmoidoscopy (say "sig-moy-DAW-skuh-pee") is a test that lets your doctor look at the inside of the lower part of your colon. The doctor looks through a lighted tube that can bend around the corners of the colon.

When used to screen for colorectal cancer, this test is usually done every 5 years. Most people who get this test also get a yearly stool test.

Getting ready for a sigmoidoscopy involves cleaning out the colon.

  • For 1 to 2 days before the test, you may be on a clear liquid diet.
  • You will likely have an enema before the test.

This test usually takes 5 to 15 minutes. It may take slightly longer if polyps are found and removed.

Risks of sigmoidoscopy

There is a small risk of problems from having a sigmoidoscopy.

There is a slight chance of piercing the colon (perforation) or causing severe bleeding by damaging the wall of the colon. But this is rare. There is also a very rare chance of a colon infection.

A sigmoidoscopy only looks at the lower part of your colon, which is where most polyps grow. But sometimes polyps grow in the upper part of your colon. Those polyps would not be seen with this test.

If your doctor finds polyps during a sigmoidoscopy, you will need to have a colonoscopy to see if there are more polyps farther up in your colon. And that test also has possible risks.

What is CT colonography?

CT colonography uses pictures taken during a CT scan to look at the colon. A thin tube is inserted into the rectum, and air is pumped through the tube into the colon. The air expands the colon so that it is easier to see on an X-ray.

This test is not done everywhere, so it may not be an option for many people. When used as a screening test, it is usually done every 5 years.

Getting ready for this test involves the same cleansing of the colon that is needed for a regular colonoscopy.

If anything is found during the CT scan, you may need to have more tests, such as a colonoscopy, to make sure that you don't have cancer.

Risks of CT colonography

There is a very small risk that the lining of the colon may be injured or torn when air is pumped into the colon. This may cause bleeding.

CT colonography may find things outside the colon that might never have caused a problem if they had not been found through screening. But this test can't tell whether the problem is harmless. So you may need more tests or treatment. This can cost a lot and cause worry.

You will be exposed to radiation during this test. There is a small chance of getting cancer from having repeated CT colonographies or other CT scans.2 The chance is higher in people who have many radiation tests.

What do experts recommend?

Experts recommend stool tests, sigmoidoscopy or sigmoidoscopy with stool tests, colonoscopy, or CT colonography to screen for colorectal cancer.

Recommendations from the U.S. Preventive Services Task Force

The USPSTF recommends that you have one of the screening tests on its suggested schedule.3 They don't recommend one test over another. Talk with your doctor to decide which test is right for you.

  • People ages 50 to 75 should have a screening test for colorectal cancer starting at age 50.
  • People ages 76 to 85 can choose whether to be screened.
  • People ages 86 and older should not be screened for colorectal cancer.

Recommendations from other groups

  • The American Cancer Society (ACS), the American Gastroenterological Association (AGA), and the American College of Gastroenterologists (ACG) recommend routine testing for people age 50 and older who have a normal risk for colorectal cancer.
  • Your doctor may recommend being tested earlier or more often if you have a higher risk for colorectal cancer. Talk to your doctor about when you should be tested.

2. Compare your options

 Stool test Colonoscopy or other procedures
What is usually involved?
  • You do the FIT or the FOBT test every year. Or you do the sDNA test every 3 years.
  • It's done at home.
  • You take samples of your stool. You may find out your results right away. Or you may need to mail the sample to a lab or your doctor's office to get the results.
  • You have one of the following procedures:
    • A colonoscopy every 10 years. It will likely be done more often if you have things that increase your risk for colorectal cancer or if polyps are found.
    • A sigmoidoscopy every 5 years, or every 10 years with the FIT stool test every year.
    • A CT colonography every 5 years.
  • These procedures are done in a doctor's office, clinic, or hospital.
  • You use laxatives to clean out your bowels.
  • With colonoscopy, you are given drugs to relax. You may not remember the test at all.
What are the benefits?
  • Screening tests work well to lower your risk of getting and dying from colorectal cancer. For example, with the FIT stool test (over 30 years):
  • It's easy to do at home.
  • A stool test costs less than other tests.
  • You don't need to use laxatives or enemas.
  • Screening tests work well to lower your risk of getting and dying from colorectal cancer. For example, with colonoscopy (over 30 years):
  • You don't have to do these tests as often as a stool test.
  • These procedures can find polyps before they turn into cancer. Polyps anywhere in the colon usually can be removed during a colonoscopy. During a sigmoidoscopy, a doctor may be able to remove polyps from the lower colon.
What are the risks and side effects?
  • A "positive" result means you will need a colonoscopy, which also has risks.
  • You may have a "positive" result from conditions that are not cancer, such as hemorrhoids or colon polyps. This could lead to worry and having a colonoscopy to make sure that you don't have cancer.
  • For all procedures
    • Bleeding problems and a tear in the colon are rare. But they are more common with colonoscopy than with sigmoidoscopy or CT colonography. With colonoscopy, this happens in less than 3 out of 1,000 people.4, 5
    • These procedures cost more than stool tests.
  • For sigmoidoscopy
    • This test only sees the lower part of the colon.
    • There may be some discomfort during the test.
    • If polyps are found, you will need a colonoscopy to see if there are more polyps farther up in your colon.
  • For CT colonography
    • If polyps are seen during this test, you will need a colonoscopy.
    • There may be some discomfort during the test.
    • This test may show problems that are outside the colon. Then other tests or treatment may be needed.
    • You are exposed to some radiation.

Personal stories

Personal stories about test methods for colorectal cancer

These stories are based on information gathered from health professionals and consumers. They may be helpful as you make important health decisions.

"No one in my family has ever had colon cancer. I try to eat a balanced diet and get plenty of exercise. I decided on FIT, since I've heard that doing this test yearly is just about as good as having a colonoscopy, but with fewer risks. And I don't have to do the bowel prep."

— Patrick, age 56

"I've had a fecal occult blood test every year for the past 4 years, and I'm going to continue with this test. My doctor gives me the kit every year and I know what foods to avoid, so it isn't a big deal."

— Jose Luis, age 54

"When I turned 50, my doctor recommended a yearly FIT with a sigmoidoscopy every 10 years. I'm okay with that. I live in a rural area and I'd have to travel quite a ways to have a colonoscopy. I'd rather have my medical care close to home."

— Frank, age 52

"I had a colonoscopy. I didn't care for the prep. I had to drink lots of fluid and stay close to the bathroom for the whole time. But the test itself was no big deal. They didn't find any polyps. I like knowing that I don't have to do this again for 10 years."

— Stella, age 58

"I chose the stool DNA test. My medical plan offers several options. I decided on the stool DNA test since I can do this one at home. My doctor said I'd need to do this test every 3 years. Now that I've done it once, I'm fine with that. The test was simple to do, and the directions were easy to follow."

— Edna, age 55

3. What matters most to you?

Your personal feelings are just as important as the medical facts. Think about what matters most to you in this decision, and show how you feel about the following statements.

Reasons to have a stool test

Reasons to have a colonoscopy or other procedure

I'm afraid of a test that involves putting anything into my colon.

I'm not too worried about having a test that involves putting something into my colon.

       
More important
Equally important
More important

I'm okay with doing a test that only checks for signs of blood in my stool.

I want to have a test that is going to see as much as possible.

       
More important
Equally important
More important

It's important to me to do testing at home, in private.

I don't mind going to a clinic or hospital to have a colonoscopy or other procedure.

       
More important
Equally important
More important

I don't like the idea of drinking a lot of laxative solution (bowel prep) and spending a long time in the bathroom before a test.

I don't mind having to do the bowel prep before a test.

       
More important
Equally important
More important

I don't want to miss any work for this test.

I'm not worried about missing work to have this test.

       
More important
Equally important
More important

I'm willing to do a stool test every year.

I want to get the test over with and not think about it for another 10 years.

       
More important
Equally important
More important

I'm worried about the cost of having a colonoscopy or other procedure.

I'm not worried about the cost of having a procedure.

       
More important
Equally important
More important

My other important reasons:

My other important reasons:

  
       
More important
Equally important
More important

4. Where are you leaning now?

Now that you've thought about the facts and your feelings, you may have a general idea of where you stand on this decision. Show which way you are leaning right now.

Using a stool test

Having a colonoscopy or other procedure

       
Leaning toward
Undecided
Leaning toward

5. What else do you need to make your decision?

Check the facts

1. Will having regular screening tests lower your chances of dying from colorectal cancer?

  • Yes
  • No
  • I'm not sure
That's right. When colorectal cancer is found early through screening tests, it is more easily treated.

2. Is colonoscopy a lot better at preventing deaths from cancer than the other screening tests?

  • Yes
  • No
  • I'm not sure
That's right. All of the screening tests are good at preventing deaths from colorectal cancer.

3. Does having a stool test mean that I won't need to have a colonoscopy?

  • Yes
  • No
  • I'm not sure
That's right. If blood is found in your stool, you need to have a colonoscopy to make sure that the blood isn't caused by cancer.

4. Will you have to do stool tests more often than you'll have to get a colonoscopy or other procedure?

  • Yes
  • No
  • I'm not sure
That's right. Depending on the test, you have to do a stool test every 1 to 3 years.

Decide what's next

1. Do you understand the options available to you?

2. Are you clear about which benefits and side effects matter most to you?

3. Do you have enough support and advice from others to make a choice?

Certainty

1. How sure do you feel right now about your decision?

     
Not sure at all
Somewhat sure
Very sure

2. Check what you need to do before you make this decision.

  • I'm ready to take action.
  • I want to discuss the options with others.
  • I want to learn more about my options.
 
Credits
ByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Primary Medical ReviewerKathleen Romito, MD - Family Medicine
Specialist Medical ReviewerKenneth Bark, MD - General Surgery, Colon and Rectal Surgery

References
Citations
  1. Dinh T, et al. (2013). Health benefits and cost-effectiveness of a hybrid screening strategy for colorectal cancer. Clinical Gastroenterology and Hepatology, 11(9): 1158–1166. DOI: 10.1016/j.cgh.2013.03.013. Accessed January 13, 2015.
  2. Einstein AJ, et al. (2007). Estimating risk of cancer associated with radiation exposure from 64-slice computed tomography coronary angiography. JAMA, 298(3): 317–323.
  3. U.S. Preventive Services Task Force (2016). Screening for colorectal cancer: U.S. Preventive Services Task Force recommendation statement. JAMA, 315(23): 2564–2575. DOI:10.1001/jama.2016.5989. Accessed June 27, 2016.
  4. Warren JL, et al. (2009). Adverse events after outpatient colonoscopy in the Medicare population. Annals of Internal Medicine, 150(12): 849–857. DOI: 10.7326/0003-4819-150-12-200906160-00008. Accessed February 2, 2015.
  5. Rabeneck L, et al. (2008). Bleeding and perforation after outpatient colonoscopy and their risk factors in usual clinical practice. Gastroenterology, 135(6): 1899–1906. DOI 10.1053/j.gastro.2008.08.058. Accessed February 13, 2015.

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