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Frequently asked questions about colon cancer screening

​​​​​​​​​​​Why do I need a screening test like colonoscopy?​

Colon cancer screening is an important tool to protect you from a disease that strikes one in eighteen Americans.

Are there other options?

A colonoscopy is the best way to spot potential problems. Virtual colonoscopy, performed by a radiologist, is also a potential way to spot polyps or growths in the colon, but does not provide a way to remove any that are found.

A home test is also an option, but colonoscopy is much more thorough.

What is a colonoscope?

This is a tubular scope that is inserted into the colon (large intestine) to examine the inside of the colon.

The scope is flexible enough to pass around the turns in the colon. It has a light so the doctor can see the inside of your colon.

Why is colonoscopy performed?

Colonoscopy is the best way to find colon cancer.

It is also used to treat polyps, evaluate symptoms and examine any abnormality seen on the barium x-ray.

What happens if a polyp is found?

During the course of the colonoscopy, a polyp may be found. Polyps are abnormal growths of tissue, which vary in size from 1/8 inch to 2 inches.  

If your doctor believes that removal of the polyp is needed, a wire loop or snare will be passed through the colonoscope. 

This will sever the polyp from the intestinal wall via an electrical current, a procedure known as polypectomy.

Polyps may be destroyed without removal and biopsies can be taken. Operating through the colonoscope often means that a major abdominal operation is not needed.

​Will I feel pain?

You should not feel much pain during treatment of the polyp.

Why are polyps removed?

They are usually removed because they can cause rectal bleeding or contain cancer. Although most polyps are benign (noncancerous), a small percentage contain an area of cancer in them or may develop into cancer.

Removal of colon polyps, therefore, is an important means of prevention and cure of colon cancer. Colon cancer is a leading form of cancer in the United States.

Are there any complications from colonoscopy and polypectomy?

Colonoscopy and polypectomy are safe and are associated with very low risk when performed by doctors who have been specially trained and are experienced in these procedures.

One possible complication is perforation, in which a tear through the wall of the bowel may allow leakage of intestinal fluids.  

This complication usually requires surgery but may be managed by hospitalization, with antibiotics and intravenous fluids in selected cases. 

Bleeding may occur from the site of polyp removal. It is usually minor and stops on its own or can be controlled by cauterization (application of electrical current) through the colonoscope. 

Rarely, transfusions or surgery may be required.

Other risks include drug reactions, and complications from unrelated diseases such as heart attack or stroke.

Death is extremely rare, but remains a remote possibility.

How do I prepare for a colonoscopy?

It is very important that you follow the instructions for preparing for your colonoscopy. Inadequate preparation or arrangements may require postponing the procedure. 

Starting the night before your procedure, you will need to take a laxative preparation to clean out your colon.

It is imperative that you follow the instructions given to you. A poorly cleaned colon can result in polyps or small tumors being missed.

How long will I be at the Clinic for my colonoscopy?

The length of time you will be at the Clinic varies for each patient. It depends on preparation needed, the procedure and recovery time.

Your appointment letter should tell you the time of your procedure appointment. The average procedure and recovery time is about 2 hours.

What should I expect before, during and after the procedure?

You may be given enemas to complete the cleaning of your colon. You may also be asked to remove dentures or glasses.  

If you wear contact lenses, make arrangements for their safe-keeping.  Do not wear makeup or jewelry on the day of your procedure.

The GI technician or the doctor will answer any questions you may have. You will be given medication to make you drowsy and comfortable during the examination.  Most people do not remember much, if anything, about the procedure.

You will remain in the recovery area for about an hour after the examination. Your doctor will discuss the results of your examination before you leave the recovery room. 

You may want a family member present when the doctor discusses these results.

After your procedure, you will be given specific instructions to follow.


A colonoscopy may be done as a diagnostic or screening test. A diagnostic test is performed to help determine what may be causing a medical problem. 

A screening test is designed to detect a medical condition before you have symptoms, especially if you are at higher risk for colon disease.

Check with your insurance carrier if you have any questions regarding your coverage. Insurance carriers and Medicare may have restrictions on their coverage for colonoscopy, depending on whether it is a diagnostic or screening test.​

Gastroenterology Contact Right Rail

Man and woman walking a dog on a gravel path Why you should get a colon cancer screening

Fifty percent. That’s the percentage of people who don’t get screened for colorectal cancer. If you’re one of the 50 percent and are 50 or older, get it done.

Here's why…

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