Colorectal cancer is the fourth most common type of cancer in men and women in the United States. (Source: The good news is, colon cancer screening dramatically reduces your risk of dying from colon cancer.

Many colorectal cancers may be prevented through removal of small growths in your colon called polyps. A colonoscopy is a test that examines the colon. Polyps can be removed during a colonoscopy. Along with getting screened for colon cancer, lifestyle changes can help prevent colon cancer. These changes include:

  • Eating a lots of vegetables, fruits and whole grains. A diet that includes many of these is linked with reducing the chance of getting colon or rectal cancer.
  • Avoiding red meat (beef, lamb, pork) and processed meats preserved by smoking, salting, curing or adding chemical preservatives — like bacon, hot dogs, ham, cold cuts, sausages, corned beef and beef jerky. Red meats and processed meats have been linked with a greater chance of getting colon cancer.
  • Getting regular exercise. Being sedentary — not being physically active — may mean you have a greater chance of developing colon cancer. You can reduce your risk by being more active.
  • Controlling your weight. If you are overweight or obese, you have a higher risk of getting or dying from colon or rectal cancer.
  • Quitting smoking. If you have smoked for many years, your chances of getting and dying from colon or rectal cancer. If you need help quitting, there are many resources, including your doctor.

Regular colon cancer screening can save your life.

It is important to get screened no matter which screening method you choose. Below is information to help you make informed decisions with your doctor about colonoscopy and other colon cancer screening methods.

What Is a Colonoscopy?

A colonoscopy is an exam that screens for colon and rectal cancer. During a colonoscopy, your doctor uses a colonoscope — a slender, flexible tube with a camera on the end — to examine the entire colon and rectum. In addition to screening for colon and rectal cancer, a colonoscopy can be used to diagnose other GI conditions including inflammatory bowel disease, abdominal pain, diverticulosis, blood with bowel movements or a change in bowel habits.

It’s a test you take every 10 years if you aren’t at high risk for colorectal cancer. During the procedure, you are given medication to help prevent pain and discomfort. This medication allows you to relax and often causes you to forget the procedure.

If your doctor finds any polyps, they are removed. Polyps can eventually become cancerous. While not every colon polyp turns to cancer, almost every colon cancer begins as a small non-cancerous polyp. During a colonoscopy, these polyps can be identified and removed or destroyed. If a polyp is large enough, tissue can be retrieved and sent for biopsy to determine the exact type of the polyp.

A colonoscopy is the gold standard for colon and rectal cancer screening, but there are other effective and non-invasive methods available. Your doctor can answer your questions about the best screening method for you. Other screening methods include:

Virtual Colonoscopy

This test uses a kind of imaging called CT colonography (X-rays and computers) to take pictures of your entire colon. A virtual colonoscopy is done every five years. A doctor called a radiologist looks at the pictures to find polyps or other abnormalities. If any abnormalities are found, your doctor will recommend that you have a colonoscopy so tissue can be removed (biopsied) and tested for colon cancer.


A sigmoidoscopy is similar to a colonoscopy because it examines your colon and rectum. However, it only looks at only the lower third of your colon rather than the entire colon. It is a test you take every five years — or if combined with a yearly FIT test, every 10 years. Your doctor will use a sigmoidoscope — a long flexible tube with a camera on the end — to examine your colon in a sigmoidoscopy. It allows your doctor to see and remove any growths like polyps and biopsy them to test for colon cancer. If the test discovers polyps or abnormal tissue, your doctor will probably recommend a colonoscopy. A sigmoidoscopy requires preparation with a drink to clear out your colon but you are not usually sedated for this exam.

Stool Tests

Stool tests are done once per year and are an option for people who are at average risk for colorectal cancer. Stool tests come in pre-packaged kits with easy-to-follow instructions. They can be done at home by gathering a stool sample to send to a lab for analysis. If the results of your stool test are concerning, your doctor will recommend that you have a colonoscopy.

With stool tests, you don’t need to drink a preparation to cleanse your colon. Stool tests look for blood in the stool in amounts that are too tiny for you to see. Blood can mean you have a polyp that is bleeding or that you have colon or rectal cancer. Blood in the stool can also mean you have another condition that is not cancer.

The three types of stool tests approved by the FDA are:

  1. gFOBT (guaiac-based fecal occult blood test), which uses a chemical to find heme, part of a protein in blood called hemoglobin. You may have to avoid certain foods before taking this test because they contain hemoglobin, which the chemical will detect.
  2. FIT (fecal immunochemical test) uses antibodies, a different way to look for the blood protein hemoglobin. You don’t need a special diet before taking this test.
  3. FIT-DNA will find the blood protein called hemoglobin. It will also find changes in DNA that can be caused by cancer. DNA from the cells lining your colon and rectum is shed into your stool. You don’t need a special diet before taking this test.

When Should I Get Screened for Colon and Rectal Cancer?

You should have your first colon and rectal cancer screening at age 45 if you are at average risk for colon or rectal cancer and continue screening until age 75. If you are older than 75, ask your doctor if you should be screened. These guidelines are currently recommended by the US Preventive Services Task Force and Centers for Disease Control.

The recommendation for the age to start colon and rectal cancer screening is 45 because studies show that rates of colorectal cancer among people younger than age 50 are increasing. You should have a conversation with your doctor about this; your doctor can help you make an informed decision.

You may need to be screened earlier than age 45 if you have:

  • A personal history of colon cancer
  • A personal history of known hereditary inflammatory colon cancer bowel disease
  • A family history of colon cancer
  • Polyps

Signs and Symptoms of Colon and Rectal Cancer Colon and rectal cancers may not have symptoms right away. If you currently have worrisome symptoms, contact your doctor immediately. Concerning symptoms include:

  • Rectal bleeding — blood with or in your bowel movements
  • Change in bowel habits
  • Abdominal pain or discomfort
  • Unexplained weight loss

Most insurance companies cover the cost of colon and rectal cancer screening starting at age 45. If you are not sure about your coverage, it’s a good idea for you to check with your insurance company before having a colonoscopy or other colorectal screening.

Schedule a Colon Cancer Screening at a Convenient Location

Talk with your primary care doctor about the colon cancer screening that is right for you. If your doctor recommends a colonoscopy or other type of screening that must be done in a hospital or health center, call 414-777-7700 to schedule your appointment at any of our convenient screening locations. Some screening locations may require a referral from your doctor.

Colonoscopy: What to Expect

Many people are afraid to get a colonoscopy, expecting it to be painful or embarrassing. Afterward, many are surprised to learn the procedure wasn’t as difficult as they expected. A little knowledge can go a long way to help you understand what it will be like and soothe any fears you may have about this important test.

Is a Colonoscopy Painful?

A colonoscopy is usually not painful. Almost all colonoscopies can be performed using “intravenous sedation” or “twilight sedation” in which you are very drowsy, but comfortable and still breathing on your own. The most common type of sedation also has a mild amnesiac effect, so most patients do not even remember the procedure. Your doctor can discuss with you the best form of sedation to suit your needs.

Preparing or “Prep” for a Colonoscopy

Colonoscopy prep is generally considered the most difficult part of the entire procedure. The good news? Once you’re done with the prep, the rest is easy. There are a variety of preparation methods for colonoscopy to rid your colon of feces. Often, a special liquid drink (of varying quantity) is used. A clean colon is essential to allow for a careful examination for polyps or other abnormalities. Your doctor will recommend the best preparation (prep) for you based on medications you take and your medical history. If you have had a previous colonoscopy, your doctor may recommend a prep based on your experience with the previous colonoscopy and the prep you used.

During a Colonoscopy

After you receive light sedation to make you sleepy, you’ll be taken to the colonoscopy procedure room. Staff will help you lie on your side on the procedure table, and make sure you are comfortable and warm with a pillow and blanket. While you are asleep, the gastroenterologist will slowly and gently insert a colonoscope (a long flexible tube with a camera and light on the end) through the anus and into your rectum and colon. During the exam, the doctor looks for polyps and other problems and removes them or takes a tissue sample for evaluation in the lab. The colonoscopy itself typically takes about 20 minutes. It can take longer, depending on findings during the exam.

Polyp Removal

If small polyps are found, a very small tool with a tiny cutting instrument is threaded through the colonoscope, and the doctor finds and snips off the tissue. If the polyp is too large to remove this way, a device called a noose is used. It has an electrified wire at the end which goes around the base of the polyp and burns it off. If the polyp is too flat or too large to safely and completely remove with a noose, the endoscopist can inject saline under the polyp to lift it. It can then be removed with the noose. This polyp removal procedure is called endoscopic mucosal resection (EMR).

Colonoscopy Recovery

Since you will be recovering from light sedation after your colonoscopy, you shouldn’t drive, make important decisions or work. We recommend you take off work on the day of your procedure. Most people can resume normal activities the day after the colonoscopy.

Why Aren't More People Getting Screened?

Screening compliance rates are influenced by many factors including: 

  • Lack of public awareness about colon cancer and of the benefits of regular screening
  • Inconsistent promotion of screening by medical care providers
  • Uncertainty among insurance providers and consumers about insurance benefits and limitations on covered benefits
  • Characteristics of the screening procedures (e.g., imperfect tests, negative attitudes towards the screening procedures)
  • Absence of social support for openly discussing and doing something about "the disease down there”