If You Are Healthy

You don't think you have a problem how, but you want to make informed decisions about your health care.

Colon Examinations

"Should I be doing self-testing at home?"

Self-testing is not desirable. There are commercially available kits that can be purchased at pharmacies. These tests are similar to the ones that are used in the doctor's office. If, however, you are doing this test to look for small amounts of blood in the stool because you have symptoms, then the sensitivity of these tests is not good enough for them to be reliable. If you have symptoms, you need to have the entire colon inspected. The cost of the physician to do the occult blood testing in the office is minimal. For all of these reasons, there is very little role for you to be self-testing at home.

"What is screening, and when should I have a screening examination?"

Screening is the process we use to look for early and unsuspected disease. Looking for problems when they are early and small makes sense. This applies to many types of cancer as well as heart disease and other common problems. Colon and rectal cancer screening looks for colon or rectal growths (cancerous and precancerous) in patients who are at normal risk for cancer, and have no symptoms to suggest that there is an abnormality in the colon. Screening should not be used for patients who have a family history of colon cancer, who have a family history of polyps of the colon, or who have a history themselves of polyps or previous cancers, or any symptoms to suggest colon growths such as rectal bleeding, change in bowel habits, abdominal pain, or weight loss. Patients in one of these categories need a barium enema or colonoscopy. In general, screening consists of looking for small amounts of blood in the stool which are not visible to the naked eye. This test is called "occult blood screening" and can be carried out in the physician's office. Another alternative is for the physician to send the patient a kit and the patient can smear a small amount of stool onto the card in the kit, and mail it back to the physician for processing. Another alternative is to examine the lower part of the colon, called the rectum with a rigid proctoscope or a flexible sigmoidoscope. A rigid proctoscope looks at a distance of 25 centimeters, where the flexible sigmoidoscopy looks at 60 centimeters. Either of these is acceptable, but increasingly the medical community is using the flexible instruments which look at more of the colon. Screening generally begins at age 40. It typically should be done once in the 40's, and twice in the 50's and annually over age 60. As we mentioned earlier, this is for patients who are at normal risk.

"Who is qualified to do a barium enema or a colonoscopy?"

Barium studies are routinely done in radiology departments. Physicians who specialize in the x-ray diagnosis of diseases are termed 'radiologists' and they are the only persons who routinely do barium enemas.
Colonoscopy, on the other hand, is done by physicians of various specialty training. In some cases, it is done by family practitioners, gastroenterologists, general surgeons, and colon and rectal surgeons. All receive specialty training in this technique. You should question your physicians about their experience and the frequency with which they do this examination. Most physicians who are experts in this area will do more than 100 examinations per year.

"Have I had an appropriate examination of my colon?"

The most important question in your mind should be whether you have had a high quality examination of your colon. This examination does not necessarily need to be carried out by a physician, but may also be carried out by other trained healthcare practitioners or personnel. In general, the examination of the colon with an instrument will require cleansing of the lower part of the colon usually with one or two small enemas given within an your prior to the examination. Several types of instruments may be used. A proctoscope is a rigid tube about 2 cm. in diameter and 25 cm. in length. An anoscope is a similar rigid tube but only about 5 cm. in length. It is usually used with flexible instruments which do not see the anus very well. Flexible instruments also vary in length. The flexible sigmoidoscope is 60cm. in length and the colonoscopy is 160 cm. in length. The colonoscope is the only instrument which looks at the entire colon. It requires more extensive bowel preparation to cleanse the entire colon and sedation during the examination. Over the age of 60, most physicians are now recommending a total colon examination at least once every 10 years.
The specifics of the examination vary from doctor to doctor. ¯ Some patients are examined when positioned on their knees, while others are lying on their side. In either case, the examination begins with carefully looking at the anus. This is followed by an examination of the anal and lower rectum with the finger. After this is completed, the instrumented is inserted and, under direct visualization, advanced to its full length. The lining of the bowel can carefully be examined. If each of these points is carried out, then you can be reassured that you have had a good examination.

"Did you find anything on my examination?"

After you have had a good examination, the only other question is whether the examiner found anything that was not normal.
The type of abnormalities that are found may not be cancerous or even precancerous. For instance, there can be polyps. Some polyps can lead to cancer, but most do not. There can be hemorrhoids; there could be other types of growths that are not precancerous, particularly in the area of the anus. Typically, these are called hypertrophied anal papillae. There may also be cracks or ulcers in the anal canal, which can cause bleeding, and pain, but which are not cancerous or precancerous.
If something that is not normal was found during the examination, the next steps should be decided through a cooperative process between you and your physician. Although persons other than physicians can perform the screening examination, if there is an abnormality, it should be visualized by a physician.

"If you find anything, how can we be certain that it is not cancer?"

The only acceptable answer to this is to go through the steps in Part Two of this book. There is no substitute for a biopsy. This is painless and can be done through the examining instrument.

"Is a benign biopsy a guarantee that the abnormality is not cancerous?"

No. The biopsy may not be representative of what the physician sees. The physician may be convinced that there are cancer cells present, but they may not be present on the biopsy. Sometimes, however, if biopsy results are uncertain or if the physician feels that a biopsy is not necessary, a repeat examination within four to twelve weeks may be appropriate. At the end of that time, if the abnormality is resolved, then nothing more needs to be done. If the abnormality persists, then a biopsy would be indicated.

"What do I need to know about growths in the colon?"

All growths in the colon begin in the lining of the bowel. These growths initially grow into the colon. Some of these growths have the potential to become cancerous, where others do not. If they do have this potential, at some time the cells become cancerous and now the growths start to grow in the other direction. As the cancer cells grow through the bowel wall, they encounter lymph vessels and blood vessels, and have the potential to spread outside the lining of the bowel. It is this capacity of cancer, to spread outside of the local growing area, that can cause spread and concern.

"Do I need a colon examination?"

In-patients who are asymptomatic and not at increased risk, it has been traditional teaching that colon examinations are not cost effective. However, increasing information is becoming available to suggest that individuals over the age of 60 should have a colon examination at least once every ten years. This can be done with either a colonoscopy or barium enema. The colonoscopy is attractive because, if successfully completed, it can visualize most of the colon; and, if a small abnormality is found, a biopsy can be taken, and the abnormality might even be removed. It is unattractive because it requires sedation and cannot be completed in about 5% of patients. Barium is less expensive and perhaps not quite as sensitive at picking up small abnormalities. Also, if an abnormality is found, a subsequent colonoscopy may be necessary to biopsy or remove it. Either of these are acceptable tests, and you should ask for the test that your physician feels is most likely to be successful and accurate in his practice.
When the whole colon is looked at, the goal is to identify any new growths or abnormalities. If this is done on a preventative basis once every ten years after the age of 60, there are statistics, which suggest that cancer deaths will be substantially decreased. ®
In individuals who have symptoms or signs or signs of cancers as were mentioned earlier, then a colonoscopy or barium enema should be performed routinely based on those symptoms. You should never be content to have just the lower part of the colon examined if it is normal. If it is abnormal, an examination of the rest of the colon is necessary to make sure that there is not a second abnormality higher in the colon. In patients who only have a family history of colon cancer, the evaluation of the colon should be performed every five years beginning ten years before the age when the cancer developed in the family member. Therefore, if you had a parent who had a colon cancer at age 55, then a colonoscopy or barium enema would be recommended every five years beginning at age 45.
It is important to recognize that the colon is unique in that it is one of the few organs where the entire organ can be well visualized, biopsies can be taken, and, most importantly, cancers are usually preceded by non-cancerous polyps. If these polyps are removed, the risk of cancer is all but eliminated from developing in the colon. There is a strong incentive for patients to have their colon checked, and thereby minimizing the risk of cancer.

"Is radiation of a barium enema dangerous?"

There is no such thing as a totally safe dose of radiation, although recent work suggests that very small doses spread out over time are less risky than the same doses if a short time. We all know some studies of patients exposed to radiation in Hiroshima and Nagasaki (large doses of radiation), as well as other intentional uses of medical x-rays in the 1950's can cause some types of cancer. However, there is no evidence that radiation will cause colon cancer. Therefore, the answer is not whether the barium enema is safe, but rather what is the risk to you, and you can feel that it is very safe.

"Is my colon examination being done correctly"

The colon examination is more complex than it might seem at first glance. A good colon examination requires a careful examination with an individual in the room who is experienced and knows how to negotiate the colon to get good visualization.
With the colonoscope, you should be adequately sedated so that the pain is minimal, and the colonoscope must be advanced throughout the entire colon. The colon has many folds and creases, and it is important to make an effort to look behind each fold and crease in an effort to visualize the colon adequately.
For barium enemas, the barium can obscure polyps that are along the side of the colon. It would be much like dropping a marble in a bottle of milk. It may be difficult to see the marble unless it is sitting just right. For this reason, it is important for the physician to have a hand on the abdomen and to thin out the column of barium as it is being inserted through the rectum. This will allow the "marble" to be seen and to be positioned against the wall of the bowel in a way that will make it more visible.

If you are going to be sedated for either a colonoscopy or a barium enema, then you will need to have someone who will take you home following the examination.

"Why is colon cleansing necessary prior to examination?"

Cleansing of the colon prior to the examination is most important to obtain an adequate examination. Inadequate cleansing can result in either inadequate visualization of the colon by the colonoscope, or a piece of stool can masquerade as a polyp and confuse the radiologist. There are multiple different types of regimens. They generally include oral intake of agents that will mechanically clean out the colon, and restricting the diet to liquids for at least 24 hours prior to the examination. The most common methods are either using a large volume of fluid to wash out the colon or a small volume of irritant which cause the bowel to increase its motility and thereby evacuating the colon. Different physicians have had experience and success with one type of cleansing or another. None is proven to be superior to another. It is your obligation to clean the colon and if you have had experience with a particular type of cleansing regimen that you find distasteful or unacceptable, then you should ask your physician for a different type of regimen. Individuals tolerate different oral cleansing agents differently, and you should not be embarrassed to address this issue with your physician or the healthcare associates in the physician's office.

"Are there other alternatives to colonoscopy or barium enema?"

Because these tests are often considered somewhat unpleasant, other alternatives have been sought. Ultrasound is being pursued but its sensitivity is very low and this point and should not be considered as an acceptable alternative. Similarly, CAT scans have been used as a "virtual colonoscopy." These CAT scans are able to see polyps that are larger than one centimeter in size, but cannot distinguish a piece of stool from a polyp. In addition, it does not see the smaller polyps which can be equally meaningful to identify. It is safe to assume that as technology improves, virtual colonoscopy may become an alternative, but it probably will not be a satisfactory alternative in the near future.

"What precautions are necessary after the colonoscopy"

Generally there are few if any restrictions following the colonoscopy. If sedations is given, someone will need to drive you home. Some physicians request patients to limit their activities and stay on a liquid diet for a few hours. Complications from colonoscopy are rare. If they occur they can happen even several weeks after the procedure and are not subtle. Usually severe pain or bleeding are the first signs of a complication after colonoscopy.

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