One of the most unpleasant methods used to screen for cancer is the colonoscopy. The procedure involves food deprivation the day before, along with the use of harsh laxatives. The following day, a specialist inserts a long tube up the rectum and pushes it through the entire colon to the appendix region. A somewhat similar technique was used during the Inquisition to extract information from suspected witches. It was a highly effective method of obtaining confessions.
|Colon cancer treatment using colonoscopy or sigmoidoscopy to remove polyps (inset). |
I had my last colonoscopy in September 2000. The doctors found one polyp, and that meant I was scheduled to have another colonoscopy in three years. As 2003 ended, I wondered if I really needed another colonoscopy after only three years. I was hoping I could find evidence that would let me wait five years like people without polyps do.
I searched the medical literature to ascertain the ideal interval between colonoscopies. Regrettably, the medical literature revealed that even more frequent screening is the prudent course of action.
The most compelling study showing the value of more frequent colonoscopies was published in the July 2, 2003, issue of the Journal of the American Medical Association (JAMA).1 This study evaluated 9,317 people who initially had negative sigmoidoscopies. When these same people repeated the procedure just three years later, a polyp or cancerous mass was detected in 13.9% of the study subjects. Based on this finding, the doctors who conducted this study raised concern that people who waited five years between colonoscopies could develop advanced cancer. A sigmoidoscopy examines only the lower third of the colon and the rectum. The consensus today is that doctors should conduct a full colonoscopy to examine and remove polyps from the entire colon and rectum.
If you are wondering why so many healthy people undergo this unpleasant procedure, a look at the grim statistics provides a persuasive argument. Cancer will kill about 563,000 Americans this year, with colorectal cancer accounting for about 57,000, or roughly 10%, of all cancer deaths.2,3 If you are a nonsmoker, your risk of lung, head and neck, pancreatic, and other cancers is significantly reduced. That makes colon cancer the type of cancer from which you are most likely to die, since the threat of contracting other cancers is so much lower.
I will discuss some startling new findings about the benefits of flexible tube colonoscopies versus virtual colonoscopies later. First, however, I am going to reveal some personal details to inform members on what I had to go through to get my latest colonoscopy performed this year.
While the American Cancer Society blames people for failing to take steps to detect cancer early, the fact is that it is becoming increasingly difficult to get medical procedures performed in an efficient manner. The result is that in today’s busy world, few Americans are taking practical steps to detect cancer in its early, curable stages.
Legislation passed in July 2001 provides coverage for all Medicare beneficiaries for average-risk screen-ing colonoscopy. Since that time, the number of average-risk screenings has increased from 4.6% before July 2001 to 14.2% after July 2001.4
The 14.2% figure still represents only a fraction of those Medicare beneficiaries who should have colonoscopies, which is one reason why colon cancer continues to kill about 57,000 Americans each year.
The Real Agony of My Colonoscopy
It is an established fact that most deaths from colorectal cancer could be avoided if more people were screened for colorectal cancers, especially high-risk individuals such as the obese and those with a family history of the disease.
While I am not overweight and do not have a family history, I would feel rather stupid if I were to contract advanced colon cancer just because I did not want to be inconvenienced by a colonoscopy.
The real agony, however, was dealing with the bureaucracy involved in arranging the procedure. First, there was the difficulty in getting through to the doctor’s office. Lots of busy signals, voicemails, and no returned phone calls. Then there were the insurance hassles, which we have all learned to expect for just about any medical procedure.
A big problem arose when the doctor insisted I first come in for a consultation, even though he had previously performed colonoscopies on me. I argued that there was no rational basis for a consultation when all I wanted was a colonoscopy. A consultation means wasted time driving to the doctor’s office, sitting in the waiting room for an hour, and sitting in the examining room for an additional thirty minutes, only to be told what day to return for the colonoscopy. I suspected that the doctor would earn a bigger insurance payment by squandering my time with a worthless consultation.
Despite my pleas to avoid the needless consultation, I was told it was required. I then resorted to finding a physician who had referred patients to this doctor. I convinced this physician to lobby the colonoscopy doctor to waive the consultation visit. It seemed like a significant victory when I received a call stating that I could have my colonoscopy without first wasting several hours on a needless consultation.
Unfortunately, the first appointment was more than two months away, and I was already overdue for this procedure. Again, I had the other physician lobby the doctor’s office to get an earlier appointment. The result was an appointment one month later.
Hold the Sedatives
A colonoscopy takes about 15 minutes to perform and can involve considerable pain and discomfort. That is why almost everyone is put on heavy-duty sedatives so that they are virtually asleep during the procedure. Some people insist on general anesthesia.
Because I do not have the luxury of missing a day of work just because of 15 minutes of pain, I routinely undergo agonizing medical procedures with no sedation. We are, after all, aging to death. I do not believe we have a day to spare not working to eradicate the aging problem. The advantage to my avoiding sedative drugs is that I am able to jump up from the table at the end of the procedure and immediately resume a productive schedule.
Doctors marvel at my insistence that no pain medication be administered. I respond that if I do not succeed in stopping aging, the agonies of aging will be a lot worse.
One Polyp Found
The result of my latest colon-oscopy was the discovery of one polyp, which was cut out and removed during the procedure. While this means I will face this colonoscopy ordeal again in three years, at least this is one type of cancer I do not have to worry about for now.
As I related near the beginning of this editorial, a recent study revealed that 13.9% of people without any colon polyps would either have polyps or some sort of cancerous mass within the following three years. So, in reality, everyone over age 40 might consider a colonoscopy every three to five years. Based on the inconvenience, expense, and inefficiencies involved, it is no wonder that so few people undergo this procedure.
Polyps are considered precancerous lesions. Some of them develop into cancer. The medical establishment does not recommend routine colonoscopies until people reach the age of 50, yet approximately 13,000 people under the age of 50 will be diagnosed with colon cancer this year.5
Most doctors are not aware that so many people under the age of 40 die of colon cancer. A surprising number of children also die of colon cancer. The reason these young adults and children so often die is that their doctors do not suspect colon cancer because they are so young. Delayed diagnosis results in sharply higher mortality. If you are obese or have a family history of the disease, you should consider having a colonoscopy, even if you are under the age of 40.
A colonoscopy is a procedure in which a long, flexible viewing tube (a colonoscope) is threaded up through the rectum for the purpose of inspecting the entire colon and rectum and, if there is an abnormality, taking a biopsy of it or removing it. The procedure requires a thorough bowel cleansing to ensure a clear view of the lining.
Problems with Virtual Colonoscopy
People generally do not like long tubes shoved up their rectums. As a result, CAT scan centers have opened across the US. These centers offer whole-body scans and “virtual” colonoscopies—high-speed x-ray devices that take a radiographic picture of the inside parts of your body, including the lining of your colon. Commercial companies have invested big money in these expensive x-ray devices and tout them as being as good as flexible tube colonoscopy.
One drawback to virtual colonoscopies is that they expose the body to a lot of ionizing radiation. The reason that so much radiation is required is that a considerable amount of fat and water contained in the lower abdominal cavity has to be penetrated in order to get a picture of your colon. Some sources estimate that the radiation exposure from a virtual colonoscopy is equivalent to that of 500 chest x-rays (or 4.5 years of natural background radiation).6,7
Ionizing radiation damages DNA, which results in the mutation of genes that regulate cellular proliferation. Many different agents damage DNA, but the good news is that DNA has the capacity to repair and reverse most of this genomic damage. What makes ionizing radiation so dangerous is that it only takes one blast to the DNA to cause permanent gene mutation.8 That is why exposure to medical x-rays (that is, to ionizing radiation) can cause cancer. Those undergoing virtual colonoscopies to detect early-stage cancer could inadvertently be increasing their risk of future cancers because of radiation-induced gene damage.
|Virtual colonoscopy: colon polyposis. |
Another disadvantage of virtual colonoscopies is that if a polyp or other suspicious lesion is detected, then flexible tube colonoscopy has to be performed anyway. If flexible tube colonoscopy is chosen in the first place, polyps and suspicious lesions can be immediately removed and a biopsy can be done to ascertain if the mass is cancerous.
A study published in the April 21, 2004, issue of JAMA compared the accuracy of conventional (flexible tube) colonoscopy to virtual (x-ray-generated image) colonoscopy in detecting polyps. The sensitivity of virtual colonoscopy was only 39% and 55% for lesions sized at least 6 millimeters and 10 millimeters, respectively. These results were significantly lower than those for conventional colonoscopy, with sensitivities of 99% and 100% for lesions sized at least 6 millimeters and 10 millimeters, respectively. In this study, virtual colonoscopy missed 2 of 8 cancers. The doctors who conducted the JAMA study concluded that virtual colonoscopy “is not yet ready for widespread clinical application…Techniques and training need to be improved.”9
Based on these data, those concerned about preventing colon cancer should choose flexible tube colonoscopy every three to five years, as opposed to virtual colonoscopy.