Patient Resources

A colonoscopy is an excellent screening exam for colorectal cancer (commonly referred to as "colon cancer"). But false information and a misplaced sense of modesty have scared some people away from these lifesaving tests.

A colonoscopy allows a doctor to see and closely look at the inside of the entire colon for signs of cancer or polyps. Polyps are small growths that over time can become cancer. The doctor uses a slender, flexible, hollow, lighted tube about the thickness of a finger. This "colonoscope" is gently eased inside the colon and has a tiny video camera, which sends pictures to a TV screen. Small puffs of air are put in the colon to keep it open and allow the doctor to see clearly.

The exam itself takes 15 to 30 minutes. Patients are usually given medicine to help them relax, which often puts them to sleep during the procedure. Your doctor decides how often you need this test, usually once every 10 years, depending on your personal risk for colon cancer. It's important for people to talk with their doctor to understand their personal risk for getting colon cancer, the guidelines they should follow for testing, and whether they need to start being tested at age 50 or earlier.

What is a colonoscopy?

A colonoscopy is an exam that allows a doctor to see and closely look at the inside of the entire colon for signs of cancer or polyps. Polyps are small growths that over time can become cancer. The doctor uses a slender, flexible, hollow, lighted tube about the thickness of a finger. This "colonoscope" is gently eased inside the colon and has a tiny video camera, which sends pictures to a TV screen. Small puffs of air are put in the colon to keep it open and allow the doctor to see clearly.

The exam itself takes 15 to 30 minutes. Patients are usually given medicine to help them relax, which often puts them to sleep during the procedure. Your doctor decides how often you need this test, usually once every 10 years, depending on your personal risk for colon cancer. It's important for people to talk with their doctor to understand their personal risk for getting colon cancer, the guidelines they should follow for testing and whether they need to start being tested at age 50 or earlier.

Will it hurt?

No, this exam is not painful. For the most part, patients are given medicine to sleep through the colonoscopy, so they won't feel anything. Air is pumped into the cleaned-out colon so it will hold its normal size and doctors can get the best pictures. While it may be slightly uncomfortable, it should not hurt.

Who will do the exam?

A colonoscopy is almost always done by a doctor, usually a gastroenterologist or a surgeon.

Will I be in a private room?

Colonoscopy is performed in a private area; it may be done in a hospital outpatient department, a clinic, an ambulatory surgery center or a doctor's office. The patient's privacy is a top concern.

How do I prepare? Will I need to miss work?

The preparation for the colonoscopy requires you to go the bathroom a lot! You follow a special diet the day before the exam and take very strong laxatives in the hours before the procedure. You may also need an enema to cleanse the colon. The key to getting good pictures is to have the colon cleaned out.

Because a colonoscopy is usually done under sedation, people usually will miss a day of work. For this test you'll need to stay close to a bathroom. You might want to schedule the procedure for a Monday, so you can be at home the day before without taking a day off work.

How will I feel afterward? Will I need someone to drive me home?

Most people feel OK after a colonoscopy. They may feel a bit woozy. They'll be watched and given fluids after the procedure as they awaken from the anesthesia. They may have some gas, which could cause mild discomfort. Because of the sedation that is given for the test, most facilities ask that you bring someone to take you home.

What if they find something?

If a small polyp is found, your doctor will probably remove it because it could eventually become cancerous. If your doctor sees a large polyp, a tumor, or anything else abnormal, a biopsy will be done. For the biopsy, a small piece of tissue is taken out through the colonoscope or sigmoidoscope. It is sent to a lab to be checked under a microscope for cancerous or precancerous cells.

Why are these tests so important?

Removing polyps prevents colorectal cancer from ever starting. And cancers found in an early stage are more easily treated. Nine out of 10 people whose colon cancer is discovered early will be alive 5 years later. And many will live normal life-spans.

But too often people don't get these tests. Then the cancer can grow and spread unnoticed, like a silent invader. In many cases, by the time people have any symptoms the cancer is very advanced and very difficult to treat.

Will a colonoscopy be covered by my insurance?

Keep in mind the cost of colorectal cancer is much more expensive to you and your family. A colonoscopy screening is usually covered by insurance. Please use this worksheet as a tool to verify your coverage with your insurance company.

A risk factor is anything that affects your chance of getting a disease such as cancer. Different cancers have different risk factors. For example, exposing skin to strong sunlight is a risk factor for skin cancer, and smoking is a risk factor for cancers of the lungs, larynx (voice box), mouth, throat, esophagus, kidneys, bladder, colon and several other organs.

But risk factors don't tell us everything. Having a risk factor, or even several risk factors, does not mean that you’ll get the disease. And some people who get the disease may not have any known risk factors. Even if a person with colorectal cancer has a risk factor, it’s often very hard to know how much that risk factor may have contributed to the cancer.

Researchers have found several risk factors that may increase a person's chance of developing colorectal polyps or colorectal cancer.

Age:

While younger adults can develop colorectal cancer, the chances of developing colorectal cancer increase markedly after age 50. More than 90% of people diagnosed with colorectal cancer are older than 50.

Personal history of colorectal polyps or colorectal cancer:

If you have a history of adenomatous polyps (adenomas), you are at increased risk of developing colorectal cancer. This is especially true if the polyps are large or if there are many of them.

If you have had colorectal cancer, even though it has been completely removed, you are more likely to develop new cancers in other areas of the colon and rectum. The chances of this happening are greater if you had your first colorectal cancer when you were younger

Personal history of inflammatory bowel disease:

Inflammatory bowel disease (IBD), which includes ulcerative colitis and Crohn's disease, is a condition in which the colon is inflamed over a long period of time. If you have IBD, your risk of developing colorectal cancer is increased, and you need to be screened for colorectal cancer on a more frequent basis (see the section, "Can colorectal cancer be found early?"). Inflammatory bowel disease is different from irritable bowel syndrome (IBS), which does not carry an increased risk for colorectal cancer.

Family history of colorectal cancer:

Most colorectal cancers occur in people without a family history of colorectal cancer. Still, as many as 1 in 5 people who develop colorectal cancer have other family members who have been affected by this disease.

People with a history of colorectal cancer or adenomatous polyps in one or more first-degree relatives (parents, siblings, or children) are at increased risk. The risk is about doubled in those with a single affected first-degree relative. It is even higher if the first-degree relative is younger than 60, or if more than one first-degree relative is affected.

The reasons for the increased risk are not clear in all cases. Cancers can "run in the family" because of inherited genes, shared environmental factors, or some combination of these.

People with a family history of adenomatous polyps or colorectal cancer should talk with their doctor about the possible need to begin screening before age 50. If you have had adenomatous polyps or colorectal cancer, it's important to tell your close relatives so that they can pass along that information to their doctors and start screening at the right age.

Inherited syndromes

About 5% of people who develop colorectal cancer have an inherited genetic susceptibility to the disease. The 2 most common inherited syndromes linked with colorectal cancers are familial adenomatous polyposis (FAP) and hereditary non-polyposis colorectal cancer (HNPCC).

Familial adenomatous polyposis (FAP): FAP is caused by changes (mutations) in the APC gene that a person inherits from his or her parents. About 1% of all colorectal cancers are due to FAP.

People with this disease typically develop hundreds or thousands of polyps in their colon and rectum, usually in their teens or early adulthood. Cancer usually develops in 1 or more of these polyps as early as age 20. By age 40, almost all people with this disorder will have developed cancer if preventive surgery (removing the colon) is not done.

FAP is sometimes associated with Gardner syndrome, a condition that also involves benign (non-cancerous) tumors of the skin, soft connective tissue, and bones.

Hereditary non-polyposis colon cancer (HNPCC): HNPCC, also known as Lynch syndrome, accounts for about 3% to 4% of all colorectal cancers. HNPCC can be caused by inherited changes in a number of different genes that normally help repair DNA damage.

This syndrome also develops when people are relatively young. People with HNPCC have polyps, but they only have a few, not hundreds as in FAP. The lifetime risk of colorectal cancer in people with this condition may be as high as 70% to 80%.

Women with this condition also have a very high risk of developing cancer of the endometrium (lining of the uterus). Other cancers linked with HNPCC include cancer of the ovary, stomach, small bowel, pancreas, kidney, ureters (tubes that carry urine from the kidneys to the bladder), and bile duct.

Turcot syndrome: This is a rare inherited condition in which people are at increased risk of adenomatous polyps and colorectal cancer, as well as brain tumors. There are actually 2 types of Turcot syndrome:

One can be caused by gene changes similar to those seen in FAP, in which cases the brain tumors are medulloblastomas.

The other can also be caused by gene changes similar to those seen in HNPCC, in which cases the brain tumors are glioblastomas.

Peutz-Jeghers syndrome: People with this rare inherited condition tend to have freckles around the mouth (and sometimes on the hands and feet) and large polyps in their digestive tracts. They are at greatly increased risk for colorectal cancer, as well as several other cancers, which usually appear at a younger than normal age. Identifying families with these inherited syndromes is important because it allows doctors to recommend specific steps, such as screening and other preventive measures, at an early age.

Because several types of cancer can be linked with these syndromes, it's important to check your family medical history for polyps or any type of cancer. If you have had adenomatous polyps or cancer, it's important to tell your close relatives. People with a family history of colorectal polyps or cancer should consider genetic counseling to review their family medical tree and determine whether genetic testing may be right for them. If needed, this can help them to decide about getting screened and treated at an early age.

Racial and ethnic background:

African Americans have the highest colorectal cancer incidence and mortality rates of all racial groups in the United States. The reason for this is not yet understood. Jews of Eastern European descent (Ashkenazi Jews) have one of the highest colorectal cancer risks of any ethnic group in the world. Several gene mutations leading to an increased risk of colorectal cancer have been found in this group. The most common of these DNA changes, called the I1307K APC mutation, is present in about 6% of American Jews.

Lifestyle-related factors:

Several lifestyle-related factors have been linked to colorectal cancer. In fact, the links between diet, weight, and exercise and colorectal cancer risk are some of the strongest for any type of cancer.

Certain types of diets:

A diet that is high in red meats (beef, lamb, or liver) and processed meats (hot dogs and some luncheon meats) can increase colorectal cancer risk. Cooking meats at very high temperatures (frying, broiling, or grilling) creates chemicals that might increase cancer risk, although it's not clear how much this might contribute to an increase in colorectal cancer risk. Diets high in vegetables and fruits have been linked with a decreased risk of colorectal cancer. Whether other dietary components (fiber, certain types of fats, etc.) affect colorectal cancer risk is not clear.

Physical inactivity:

If you are not physically active, you have a greater chance of developing colorectal cancer. Increasing activity may help reduce your risk.

Obesity:

If you are very overweight, your risk of developing and dying from colorectal cancer is increased. Although obesity raises the risk of colon cancer in both men and women, the link seems to be stronger in men.

Smoking:

Long-term smokers are more likely than non-smokers to develop and die from colorectal cancer. Smoking is a well-known cause of lung cancer, but some of the cancer-causing substances are swallowed and can cause digestive system cancers, such as colorectal cancer.

Heavy alcohol use:

Colorectal cancer has been linked to the heavy use of alcohol. At least some of this may be due to the fact that heavy alcohol users tend to have low levels of folic acid in the body. Still, alcohol use should be limited to no more than 2 drinks/day for men and 1 drink/day for women.

Type 2 diabetes:

People with type 2 (usually non-insulin dependent) diabetes have an increased risk of developing colorectal cancer. Both type 2 diabetes and colorectal cancer share some of the same risk factors (such as excess weight). But even after taking these into account, people with type 2 diabetes still have an increased risk. They also tend to have a less favorable prognosis (outlook) after diagnosis.

For this test, the doctor looks at the entire length of the colon and rectum with a colonoscope. It is inserted through the rectum into the colon. The colonoscope has a video camera on the end that is connected to a display monitor so the doctor can see and closely examine the inside of the colon. Special instruments can be passed through the colonoscope to remove (biopsy) any suspicious looking areas such as polyps, if needed.

Before the test: Be sure your doctor is aware of any medicines you are taking, as you may need to change how you take them before the test. The colon and rectum must be empty and clean so your doctor can view their inner linings during the test. You will need to take laxatives (liquids, pills, or both) the day before the test and possibly an enema that morning. Your doctor will give you specific instructions. It is important to read these carefully a few days ahead of time, since you may need to shop for special supplies and get laxatives from a pharmacy. If you are not sure about any of the instructions, call the doctor's office and go over them step by step with the nurse. Many people consider the bowel preparation to be the most unpleasant part of the test, as it usually requires you to be in the bathroom quite a bit.

You may be given other instructions as well. For example, your doctor may instruct that you drink only clear liquids (water, apple or cranberry juice, and any gelatin except red or purple) for a day or 2 before the exam. Plain tea or coffee with sugar is usually okay, but no milk or creamer is allowed. Clear broth, ginger ale, and most soft drinks or sports drinks are usually allowed unless they have red or purple food colorings, which could be mistaken for blood in the colon.

You will likely also be told not to eat or drink anything after midnight the night before your test. If you normally take prescription medicines in the mornings, talk with your doctor or nurse about how to manage them for the day.

You may need to arrange for someone to drive you home from the test because the sedative used during the test can affect your ability to drive. Depending on the medicines that are used, some doctors require that someone drive you home.

During the test: The test itself usually takes about 30 minutes, although it may take longer if a polyp is found and removed. Before the colonoscopy begins, you will be given a sedating medicine (usually through your vein) to make you feel comfortable and sleepy during the procedure. You will probably be awake, but you may not be aware of what is going on and may not remember the procedure afterward. Most people will be fully awake by the time they get home from the test.

During the procedure, you will be placed on your side with your knees flexed and a drape will cover you. Your blood pressure, heart rate, and breathing rate will be monitored during and after the test.

Your doctor should do a digital rectal exam (DRE) before inserting the colonoscope. The colonoscope is lubricated so it can be easily inserted into the rectum. Once in the rectum, the colonoscope is passed all the way to the beginning of the colon, called the cecum. If you are not sedated, you may feel an urge to have a bowel movement when the colonoscope is inserted or pushed further up the colon. To ease any discomfort it may help to breathe deeply and slowly through your mouth. The colonoscope will deliver air into the colon so that it is easier for the doctor to see the lining of the colon and use the instruments to perform the test. Suction will be used to remove any blood or liquid stools.

The doctor will look at the inner walls of the colon as he or she slowly withdraws the colonoscope. If a small polyp is found, the doctor may remove it. Some small polyps may eventually become cancerous. For this reason, they are usually removed. This is usually done by passing a wire loop through the colonoscope to cut the polyp from the wall of the colon with an electrical current. The polyp can then be sent to a lab to be checked under a microscope to see if it has any areas that have changed into cancer.

If your doctor sees a larger polyp or tumor or anything else abnormal, a biopsy may be done. For this procedure, a small piece of tissue is taken out through the colonoscope. The tissue is looked at under a microscope to determine if it is a cancer, a benign (non-cancerous) growth, or a result of inflammation.

The bowel preparation before the test can be unpleasant. The test itself may be uncomfortable, but the sedative usually prevents this, and most people feel normal once the effects of the sedative wear off. Some people may have gas pains or cramping for a while after the test.

In some cases, people may have low blood pressure or changes in heart rhythms due to the sedation during the test, although these are rarely serious.

If a polyp is removed or a biopsy is done during the colonoscopy, you may notice some blood in your stool for a day or 2 after the test. Significant bleeding can occur with a colonoscopy, but it is still uncommon. In rare cases, continued bleeding might require treatment.

Although colonoscopy is a safe procedure, on rare occasions the colonoscope can puncture the wall of the colon or rectum. This is called a perforation. It can be a serious complication and at times requires surgical repair. Talk to your doctor about the risk of this complication.

Excluding skin cancers, colorectal cancer is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society's most recent estimates for the number of colorectal cancer cases in the United States are for 2009:

106,100 new cases of colon cancer (52,010 in men and 54,090 in women)
40,870 new cases of rectal cancer (23,580 in men and 17,290 in women)

Overall, the lifetime risk for developing colorectal cancer is about 1 in 19 (5.3%). This risk is slightly higher in men than in women. A number of other factors affect a person's risk for developing colorectal cancer.

Colorectal cancer is the third leading cause of cancer-related deaths in the United States when men and women are considered separately, and the second leading cause when both sexes are combined. It is expected to cause about 49,920 deaths (25,240 in men and 24,680 in women) during 2009.

The death rate (the number of deaths per 100,000 people per year) from colorectal cancer has been dropping for more than 20 years. There are a number of likely reasons for this. One is that polyps are being found by screening and removed before they can develop into cancers. Screening is also allowing more colorectal cancers to be found earlier when the disease is easier to cure. In addition, treatment for colorectal cancer has improved over the last several years. As a result, there are now more than 1 million survivors of colorectal cancer in the United States.

A colonoscopy screening is usually covered by insurance. Please use this worksheet as a tool to verify your coverage with your insurance company.