By James Church
WebMD Live Events Transcript
The opinions expressed herein are the guest's alone. If you have questions about your health, you should consult your personal physician. This event is meant for informational purposes only.
Learning that you have colon cancer is frightening, but if caught early enough, this disease is highly treatable and often curable. Learn about the latest diagnostic tools and treatments for colon cancer when James Church, MD, joined us from The Cleveland Clinic.
Moderator: Welcome to WebMD Live. Today our guest is James Church, MD, from The Cleveland Clinic. He'll answer your questions about colon cancer. Thank you for joining us today, Dr. Church. Every year, more than 130,000 people are told they have colorectal cancer, and more than 46,000 colon cancer-related deaths occur. Yet when detected early, colorectal cancer can be effectively treated -- even cured. What is stopping early detection?
Church: The first thing is that a lot of people are reluctant to get screened. The second thing is that the easy screening tests are not completely accurate. The most accurate screening test is relatively invasive and expensive.
Moderator: Please explain the various tests for colorectal cancer. What is involved in each and which is most effective at detecting cancer?
Church: The simplest test is fecal blood testing which is cheap and easy but has a relatively high rate of false negative and false positive results. The best test is colonoscopy, which will detect almost all cancers and the great majority of polyps (the premalignant phase of cancer). It also allows removal of the premalignant polyps. However, colonoscopy is an invasive test and is the most expensive. A barium enema is an X-ray of the colon that is less invasive and less expensive than colonoscopy but is less accurate and does not allow any treatment. Flexible sigmoidoscopy is similar to a colonoscopy involving inspection of only the lower third of the colon. It is less invasive than colonoscopy but leaves two-thirds of the colon unexamined.
Moderator: How is a colonoscopy performed?
Church: The principle of the test is to insert a six-foot-long flexible endoscope [into] the six-foot long colon after the colon has been cleaned. As the endoscope is removed, the colon lining is carefully inspected. Patients are often sedated, as the examination may be somewhat uncomfortable.
Moderator: Can you explain a "virtual" colonoscopy?
Church: Virtual colonoscopy, or CT colonography involves a CT scan of the abdomen performed when the colon has been cleaned and inflated with air. The information from the scan is processed by computer and a three-dimensional reconstruction of the colon is produced. This reconstruction can be inspected as if the physician were "flying through" the colon. The examination appears to be as accurate as a barium enema but again, does not allow treatment or biopsy of abnormalities.
Member: As a 39-year-old woman with colorectal cancer in my family history, when should I have my first colonoscopy?
Church: It depends on how old your relatives were when they were diagnosed and how closely related they are to you. The younger the relative and the closer they are to you, the higher your own risk. If you have a first-degree relative -- parent, sibling, children -- affected under the age of 50, you should have a colonoscopy at age 40, or 10 years younger than the age at which your relative was diagnosed. If your affected relative was over 65, a colonoscopy at 50 is probably adequate.
Member: Are there any warning signs? Is this something I should be getting tested for every year?
Church: The principle of prevention is to find and treat polyps and cancers before symptoms develop. Once symptoms have developed, the chance of cure is only 50-60%. Relevant symptoms are colorectal bleeding and a lasting change in bowel habit. For average-risk people, colon screening should start at age 50. The recommendations include: colonoscopy every 10 years after that age or yearly fecal blood testing with flexible sigmoidoscopy every five years or barium enema every 10 years. Most physicians prefer to recommend colonoscopy because of its accuracy and therapeutic potential.
Moderator: What are the risk factors for colorectal cancer? Who is at risk?
Church: We all are at risk as citizens of the U.S. because of our diet and lifestyle. The average risk in this country is between 4% and 6% in a person's lifetime. Groups at high risk include those with a family history of colorectal polyps or cancer, people who have had a polyp or cancer themselves already, people that have had colitis for 14 years or more.
Moderator: Can you further explain the role of diet as a causative factor and in prevention?
Church: Colorectal cancer and polyps arise because of an accumulation of mutations in genes that regulate cell growth and death. These mutations are caused by carcinogens (cancer-causing chemicals) that primarily come from red meat and animal fats. Dietary factors that prevent or protect against mutations are fresh fruits and vegetables and fiber.
Member: So would you say that high-protein diets that are so popular now might contribute to colon cancer down the road?
Church: It would depend on the source of the protein. There is some evidence that fish is beneficial to the heart and possibly to the colon. Protein derived from red meat, however, is likely to increase the carcinogen load in the colon.
Member: In a proper preventive diet, is chicken also a "good" protein source? Is pork a "red" meat?
Church: The evidence we have really incriminates red meat. However, the process of grilling or barbecuing meat, producing the blackening that is so tasty, is also very good at producing carcinogens.
Moderator: Is there anything besides diet that we can do to prevent colorectal cancer?
Church: I had mentioned that chronic colitis is a risk factor for colon and rectal cancer. If a patient has ulcerative colitis or Crohn's disease for longer than 10 years they should undergo regular colonoscopy with biopsies to make sure that precancerous changes are not occurring.
Moderator: What about irritable bowel syndrome?
Church: There is no relationship between irritable bowel syndrome and colorectal cancer. IBS is the most common cause of symptoms such as abdominal cramps, diarrhea, and constipation. These sorts of symptoms are rarely caused by colorectal cancer.
Member: I had a total proctectomy and colectomy plus permanent ileostomy in August 1978, due to ulcerative colitis. There were no measures taken to help heal the proctectomy. It has been debilitating due to pain, ever since, but my HMO won't touch it. I had a second opinion from outside, and he confirmed that no instruments were left in there. It goes into spasm sometimes, where the sphincter was. Excruciating! Is this worth a trip for me to Cleveland to see you? My colectomy/proctectomy was done after I had had ulcerative colitis for some 10 years. It did not respond to any treatment, so they took it out to prevent cancer. Was that a smart move? I had no polyps, no malignancies, and no history of any relatives having had it.
Church: We would be happy to do an evaluation of the symptoms if they are troubling you enough to make the trip to Cleveland worthwhile. In our department, we are very experienced with patients who have ulcerative colitis and Crohn's disease and I think that probably would be worth the trip. I think that you would have been facing a colectomy at some time in your life. The timing of it is hard to judge while looking back at events. The word "proc" refers to the rectum so a proctectomy refers to removal of the rectum. A proctocolectomy means removal of the entire colon and the rectum. The most common surgery for colon cancer is removal of the right side or the left side of the colon depending on where the cancer is. Proctocolectomy is usually performed for colitis or familial polyposis.
Moderator: What treatments are available now to treat colorectal cancer? What new treatments are coming?
Church: The only curative treatment for colorectal cancer is surgery, and the only way surgery is successful is if all malignant cells are removed. Sometimes, malignant cells have spread to a place where they cannot be removed. This is where radiation or and/or chemotherapy has a role.
Member: When I read about colorectal cancer survival rates, are stages 1-4 lumped together?
Church: When a single survival rate is given, it is usually the survival of all patients treated for cure. This means that patients who are incurable are not included. The survival rate (the percentage of patients alive for five years are surgery) for stage 1 cancer should be close to 100%. For stage 2 cancer, it should range between 85-90%. For stage 3, between 65-70%, and for stage 4 generally 5-15%.
Member: What is the survival rate of stage 4 colorectal cancer patients? My father is 62, had colostomy last year and has a CEA of 240, which decreases with each chemo round. What might be his long-term survival? And what is the significance of CEA test results? I can't find a chart that ranks the CEA numbers.
Church: Lets go with CEA. The letters stand for carcinoembryonic antigen. This is a protein produced by cancer cells and measured in the blood. It is usually specific to cancer that has spread to the liver. The normal range in nonsmokers is less than 2.3 but in people who smoke, up to 5.0 is normal. Unfortunately, it seems that your father has some cancer in the liver but this is being contained with the chemotherapy. It is extremely unlikely that your dad will be cured but people have survived from two to five years with liver metastases for colorectal cancer.
Member: A family member has recently been diagnosed with colon cancer along with several spots on his liver. Does this mean that it is in the advanced stages and is possibly in the lymph nodes?
Church: The liver is the most common site for colon cancer to spread because blood from the colon goes directly to the liver. Once colon cancer has spread to the liver, this is stage 4 disease and the chances of cure are slim. When a colon cancer has spread to the lymph nodes, this is stage 3 disease. Patients with stage 3 disease have approximately 50% chance of developing liver metastases. Such patients are routinely offered chemotherapy after their surgery to try and prevent the liver disease from occurring.
Member: Is surgery plus chemo successful, or is the deck stacked, the way you suggested before -- less than 50% by that time, perhaps?
Church: The success of treatment is closely related to the stage of the cancer at the time it is removed. The stage of the cancer represents the results of a battle between the body's defenses and the aggressiveness of the cancer. Therefore, someone with good defenses or a cancer that is not very aggressive will have an "early" (stage 1 or 2) cancer while a person whose defenses are weak or whose cancer is aggressive will have an advanced cancer (stage 3 or 4). As we said, almost everyone with stage 1 or 2 cancers can be cured. Only about half of the patients with stage 3 cancer can be cured using the most modern surgical and chemotherapy techniques.
Member: How can we find out about those "stages?"
Church: The only way to accurately stage a colon cancer is to send the cancer itself and the other tissue that was removed at surgery to the laboratory. Here, the cancer is examined under the microscope, as are the lymph nodes that were removed with it. The situation is a little different for rectal cancer that can be staged before surgery using techniques such as ultrasound or MRI scanning. This allows radiation to be given before surgery for rectal cancers to reduce the risk of cancer recurrence and to improve survival.
Member: So smoking and beer consumption can definitely contribute to the development?
Church: Smoking and beer consumption are two of several lifestyle factors that have been associated with the risks of colon cancer. It is unclear however how strong a relationship between these particular factors and risk of colon cancer is. I suspect that they just reflect an unhealthy lifestyle in general that also includes an unhealthy diet, lack of exercise, and carrying too much weight. It is very difficult to separate out individual factors when this is happening.
Member: Last year both my mother and my sister had blood in their stools and were checked and no cause was found. Now I have noticed some in mine. Should I be checked?
Church: Definitely! Blood in the stools is never normal and there should always be an explanation. The type of bleeding is important in predicting what the cause is. Bright red blood on the toilet paper or in the water is most likely coming from hemorrhoids. This should stop if you stop straining to pass stools or by improving your diet. Black blood on or in the stool is much more suspicious. I hope that you and your family have had colonoscopies as this is the only reliable way of making sure that the blood is not coming from a polyp or a cancer.
Moderator: What advice can you give to someone helping a family member going through treatment for colon cancer? What might they expect to encounter?
Church: Everybody with colon and rectal cancer will need to have a major abdominal surgery. This will involve six to seven days in the hospital and six weeks convalescence. This is a major trauma to the body and although if the patient is otherwise fit and well they bounce back easily, in elderly patients with other illnesses a recovery can take some time. The chemotherapy used for colon cancer is not particularly harmful. It does not cause hair loss and at worst, may cause a mild nausea. Radiation therapy is only given for rectal cancer but can cause diarrhea and painful bowel movements. When it is given with chemotherapy, the side effects may be worse. Sometimes it is necessary to stop the treatments while the patient recovers.
Member: I read that you utilize sphincter-sparing procedures. What are the determining factors for leaving the sphincter (anus)?
Church: The most important priority in treating patients with rectal cancer is to cure the cancer. In order to do that, we like to take a margin of one inch of healthy rectum below the cancer. If the cancer is within one inch of the sphincter muscles, then we cannot move this margin without removing the sphincter muscles themselves and therefore a permanent colostomy is needed. However, if the cancer is one inch or more above the sphincter muscles then the rectum can be removed, the cancer cured and the sphincter preserved. A permanent colostomy is not necessary therefore.
Member: I have had polyps removed. If I keep getting the checkups, and keep getting the polyps, if any, removed, will I keep cancer at bay?
Church: The simple answer is yes, as all colon cancers start as a polyp. However, in the real world, colonoscopy is not 100% accurate. Polyps and cancers may go unnoticed and if there is a long time between examinations, a polyp that was not seen could conceivably turn into a cancer.
Moderator: We are almost out of time. Before we wrap up for today, do you have any final comments for us?
Church: The most important thing that people could do to stop getting colon cancer or to find it at a curable stage is to be checked. I suggest that everybody talk to their physician about their own risk status for colon cancer and about what would be the most suitable case for them.
Moderator: Unfortunately, we are out of time. Thanks for joining us, members, and thanks to James Church, MD, for being our guest. For more information, visit our Colorectal Cancer Condition Center. That's where you can find the new "Guide to Colorectal Cancer" provided by The Cleveland Clinic. Until then, be well and goodbye!
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