Published on July 23, 2021

Colon Cancer Screening: Colonoscopy vs. Home Screening

group of adults

Why is colon cancer screening important?

  • Colon cancer is the third most common cancer in both men and women in the U.S.
  • One in 20 people will be diagnosed with colon cancer in their lifetime
  • Screening allows cancer to be diagnosed and treated sooner, before symptoms develop or cancer spreads

What symptoms can be seen with colon cancer?

  • Changes in bowel habits that last for more than a few days
  • Blood in the stool
  • Abdominal pain
  • Unintentional weight loss
  • Fatigue and weakness

When should I start screening for colon cancer?

  • Typically, colon cancer screening should start at age 50. However, the American Cancer Society recommends screening start earlier at age 45 because of the incidence of colon cancer now occurring in younger age groups. Discuss this decision with your doctor and check with your insurance carrier.
  • If you have a family history of colon cancer, an inherited polyposis syndrome, or a form of inflammatory bowel disease (such as Crohn’s or ulcerative colitis), colon cancer screening should be started earlier. Again, discuss this with your doctor.

What is expected with colonoscopy screening?

  • A colonoscopy is a procedure that allows a gastroenterologist to use a scope with a camera to look inside the colon. During this procedure, biopsies can be taken and polyps removed. This makes colonoscopy screening the gold standard.
  • The day before your test, you will need to drink a bowel prep that cleanses out the colon to allow for optimal visualization of the colon.
  • You may also have to hold medications such as blood thinners or insulin, but this will be discussed with your doctor prior to the test.
  • Sedation is necessary, so you will need someone to drive you home after the procedure.
  • As with any procedure, there is a small risk of complication. This includes infection, bleeding and tears in the bowel. However, this risk if quite small and does not outweigh the risks associated with undiagnosed colon cancer.

How often should I get a colonoscopy?

  • If you are at average risk for colon cancer, then colonoscopy screening is every 10 years.
  • Colonoscopy should be continued until age 75 or until life expectancy is less than 10 years.
  • If adenomatous or serrated polyps are found, colonoscopy is recommended sooner because of a higher risk of malignancy (this depends on the size of the polyps and how many were removed, so discuss screening interval recommendations with your physician).
  • If symptoms develop between screening intervals, you may need to have colonoscopy done sooner.

What is expected with a FIT (fecal immunochemical test)?

  • FIT is done at home and detects blood in the stool.
  • FIT should be performed every year starting at age 50.
  • FIT cannot detect polyps and does not allow for direct visualization of the colon, or biopsies, which can miss some cancers.
  • No sedation, bowel prep, dietary modifications or medication restrictions are indicated.
  • There is a risk of false-positive results with FIT.
  • If the test returns positive, then colonoscopy screening is indicated.

What is Cologuard screening?

  • Cologuard is a stool DNA test that is done every three years.
  • Cologuard test is done at home with no bowel prep, sedation, or dietary or medication restrictions.
  • Cologuard test does not allow for direct visualization of .the colon, polyps removal or biopsy.
  • Cologuard test has a risk of false-positive results.
  • If Cologuard test is positive, colonoscopy is indicated.

Myths vs. Fact

Myth: I feel fine, so I don’t need colon cancer screening.
Fact: It is common for people to go undiagnosed with colon cancer because often there are no symptoms in earlier stages.

Myth: I can’t tolerate the bowel prep.
Fact: The bowel prep solution has improved a lot over the years. Is now a smaller amount, and most patient tolerate it well.

Myth: It hurts to have a colonoscopy.
Fact: You will be under sedation during the procedure, so you will not experience any pain.

Myth: There is nothing I can do to decrease my risk of colon cancer. What will happen will happen anyway.
Fact: Colonoscopies allow for pre-cancerous polyps to be removed to avoid the development of cancer in the future.

What can I do to decrease my risk of colon cancer?

  • Avoid smoking and alcohol use
  • Engage in regular exercise and maintain a healthy weight
  • Avoid processed and red meat

Many people avoid colonoscopy at all costs. Is home screening for colon cancer just as good?