martyb
Thinks s/he gets paid by the post
Ouch!!! 
Colonoscopy, Guess What
- Thread starter poboy
- Start date
audreyh1
Give me a museum and I'll fill it. (Picasso) Give me a forum ...
Best of luck to you poboy! I'm so glad you caught it early enough for a good prognosis (I hope). Do you get to avoid chemo? My MIL is at very advanced colon cancer right now and it's not pretty!poboy said:
Audrey
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poboy
Recycles dryer sheets
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- Jan 28, 2006
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According to my doctors I will not need any chemo/radiation therapy. Been in once for a check by the surgeon, will return in six months for a flex sigmoidoscopy and then back to my gastroenterologist for colonoscopies. I do not know what time intervals will be, annual or every 2-3 years.
I had my colonoscopy done a couple of years ago. I told the doctor that I thought it would be neat to watch it. I was watching it as it started and I can remember asking the doctor if he could stop just for a moment and that is the last thing I remember! I remember waking up and my spouse being there and I told him that the doctor was going to come talk to us. The nurse said that the doctor had already come and gone. He was a smart doctor and knew he needed to put my out to git her done!
Colonoscopy vs Flexible sig/fecal occult blood test
Does anyone have stats comparing the improvement in diagnostics
for colonoscopy vs flexible sig/fecal occult blood test vs the increased risk
of colonscopy (perforations/bleeding/anesthesia/etc.)
I understand that my medical clinic has adopted colonoscopy as the preferred method. It makes sense that colonoscopy would be better at diagnostics since you are view a larger area but we have personal knowledge of a friend who had bleeding at home after being released from the clinic so I would like to understand the risk/reward tradeoff a
bit better quantitatively.
Does anyone have stats comparing the improvement in diagnostics
for colonoscopy vs flexible sig/fecal occult blood test vs the increased risk
of colonscopy (perforations/bleeding/anesthesia/etc.)
I understand that my medical clinic has adopted colonoscopy as the preferred method. It makes sense that colonoscopy would be better at diagnostics since you are view a larger area but we have personal knowledge of a friend who had bleeding at home after being released from the clinic so I would like to understand the risk/reward tradeoff a
bit better quantitatively.
Rich_by_the_Bay
Moderator Emeritus
kaneohe said:
66% of advanced colon polyps, cancers can be reached with the flex. sigmoidoscopy in men, 40% in woman (polyps tend to be farther in). 100% are within reach of colonoscpy (a few are always missed for technical reasons). Perforation risk: .88 per 1000, but positive test requires colonoscopy anyway.
Fecal occult blood, properly done: detects over 90% of cancers and polyps, but only 2% of patients with positive tests have cancer. That is, it's likely to be abnormal when there is trouble, but it is usually abnormal (97-98% of the time) because of some other reason such as hemorrhoids; this leads to 49 out of 50 follow-up colonoscopies being unrevealing for cancer.
Colonoscopy: finds over 95% of cancer and polyps over 1 cm (smaller ones have low cancer risk). Perforation risk: 1-2 per 1000.
Colon cancer is reduced by anywhere from 17% (fecal blood tests) to 54%, colonoscopy.
Here is a long excerpt from a good patient information sheet:
Patient information: Screening for colon cancer
Robert H Fletcher, MD [UTD]
These materials are for your general information and are not a substitute for medical advice. You should contact your physician or other healthcare provider with any questions about your health, treatment, or care. Please do not contact UpToDate or the physician authors of these materials....
WHY IS SCREENING EFFECTIVE? — Most colorectal cancers develop gradually over many years. They begin as small, benign tumors called adenomatous polyps. These polyps grow, develop precancerous changes, eventually become cancerous, and later spread and become incurable. This progression takes at least 10 years in most people.
The screening tests described below all work by detecting pre-cancers at the polyp stage before they become cancerous or by detecting cancers themselves while they are still curable. Regular screening for and removal of polyps can reduce a person's risk of developing colorectal cancer by up to 90 percent. In addition, early detection of cancers that are already present in the colon often allows for successful treatment.
...
Fecal Occult Blood
Effectiveness — The fecal occult blood test, when performed once every year, has been shown to reduce the risk of dying from colorectal cancer by up to one-third [1].
Risks and disadvantages — Because polyps seldom bleed, the fecal occult blood test is less likely to detect polyps than other screening tests (see below). In addition, only 2 to 5 percent of people with a positive test actually have colorectal cancer; thus, for every patient with cancer, 50 patients are unnecessarily distressed and undergo tests that eventually reveal no cancer. Following the procedures discussed above will reduce the chance of a false-positive test.
Additional testing — If a fecal occult blood test has a positive result, your doctor will recommend that the entire colon be examined, usually with colonoscopy.
Sigmoidoscopy — Sigmoidoscopy allows direct viewing of the lining of the rectum and the lower part of the colon (the descending colon). This area accounts for about one-half of the total area of the rectum and colon, where half of the cancers occur. (See "Patient information: Flexible sigmoidoscopy").
Procedure — Sigmoidoscopy requires that the patient prepare by cleaning out the bowel. This usually involves consuming a clear liquid diet, laxatives, and the using an enema shortly before the examination. During the procedure, a thin, lighted tube is advanced along the rectum and the left side of the colon to check for polyps and cancer. Biopsies (small samples of tissue) can be removed during sigmoidoscopy. Sigmoidoscopy may be performed in a doctor's office; because this procedure produces only mild cramping, most people do not need sedative drugs and are able to return to work or other activities the same day.
Effectiveness — Physicians who perform sigmoidoscopy can identify polyps and cancers in the descending colon and rectum with a high degree of accuracy. Studies suggest that sigmoidoscopy, performed as infrequently as every 5 to 10 years, reduces death from cancers in the lower half of the colon and rectum (the area directly examined) by 66 percent [2].
Risks and disadvantages — The risks of sigmoidoscopy are low. The procedure can create a small tear in the intestinal wall in about 2 per every 10,000 people; death from this complication is rare. A major disadvantage of sigmoidoscopy is that it cannot detect polyps or cancers located in the right side of the colon.
Additional testing — Certain changes in the left-sided colon increase the likelihood of polyps or cancer in the remaining part of the colon. Thus, if sigmoidoscopy reveals suspicious findings in the left-sided colon, such as many small polyps or polyps with certain microscopic features, the physician may recommend colonoscopy to view the entire length of the colon.
Combination of fecal occult blood test and sigmoidoscopy — Combined screening with a fecal occult blood test and sigmoidoscopy is a common practice and may be more effective than screening with either test alone [3].
Colonoscopy — Colonoscopy allows direct viewing of the lining of the rectum and the entire colon. (See "Patient information: Colonoscopy").
...
Effectiveness — Colonoscopy detects most small polyps and almost all large polyps and cancers [4]. Polyps and some cancers can be removed during this procedure.
Risks and disadvantages — The risks of colonoscopy are greater than those of other screening tests. Colonoscopy leads to serious bleeding or a tear of the intestinal wall in about 1 in 1,000 people. Because the procedure requires sedation, most people must be accompanied home after the procedure and are unable to return to work or other activities on the same day.
...
Virtual colonoscopy, in particular, is being performed more commonly. The major advantages of virtual colonoscopy compared with optical colonoscopy are that the procedure is safe, and you do not need to be sedated. However, if a worrisome polyp is found on virtual colonoscopy, you will need to undergo optical colonoscopy for confirmation and biopsy. Additionally, the accuracy of virtual colonoscopy appears to vary depending on the specifics of how it is performed. The kind of virtual colonoscopy that is widely available may not be accurate enough to be appropriate for use as a screening test.
SCREENING PLANS — Different screening plans are recommended for people with an average risk of colorectal cancer and people with an increased risk of colorectal cancer.
Screening plans for people with an average risk of colorectal cancer — Doctors usually recommend that people with an average risk of colorectal cancer begin screening at age 50. The tests differ in features (effectiveness in preventing cancer, comfort, safety, cost, and convenience) that may matter to you. No single screening test has been identified as the best test. You should discuss the available options with your doctor and design a screening plan that is best for you. The most important thing is that you follow through with the screening plan.
Some doctors recommend a fecal occult blood test once every year and a sigmoidoscopy once every five years; they may also recommend a combination of these screening tests. Other doctors recommend a barium enema test once every five years or colonoscopy once every 10 years.
If any of these screening tests has a positive result, your doctor will probably recommend more frequent examinations with colonoscopy; this is referred to as surveillance.
Screening plans for people with an increased risk of colorectal cancer — When compared to screening programs for people with an average risk, programs for people with an increased risk may entail screening at a younger age, more frequent screening, and the use of more sensitive screening tests (like colonoscopy). For people who have an increased risk of colorectal cancer, the optimal screening plan depends upon the cause of increased risk.
Family history of colorectal cancer
People who have one first-degree relative (parent, brother, sister, or child) who has experienced colorectal cancer or adenomatous polyps at a young age (before the age of 60 years), or two first-degree relatives diagnosed at any age, should begin screening earlier, typically at age 40, or 10 years younger than the earliest diagnosis in their family, whichever comes first, and screening should be repeated every five years.
People who have one first-degree relative (parent, brother, sister, or child) who has experienced colorectal cancer or adenomatous polyps at age 60 or later, or two or more second degree relatives (grandparent, aunt, uncle) with colorectal cancer should begin screening at age 40, and screening should be repeated as for average risk people.
People with a second-degree relative (grandparent, aunt, or uncle) or third-degree relative (great-grandparent or cousin) with colorectal cancer may be screened as average risk people.
Familial adenomatous polyposis — People with a family history of familial adenomatous polyposis (FAP) should consider genetic counseling and genetic testing to determine if they carry the affected gene. People who carry the gene or who do not know if they carry the gene should begin screening with sigmoidoscopy once every year, beginning at puberty. When this screening reveals many polyps, a person should begin to plan colectomy (surgical removal of the colon) with their doctor; this surgery is the only certain way to prevent colorectal cancer in people with FAP.
Hereditary nonpolyposis colon cancer — People with a family history of hereditary nonpolyposis colon cancer (HNPCC) should consider genetic counseling and genetic testing to determine if they carry the affected gene. People who carry the gene or who do not know if they carry the gene should be screened with colonoscopy or barium enema because HNPCC is associated with cancers of the right-sided colon. This screening should be scheduled once every one to two years between the ages of 20 and 30, and once every year after the age of 40. Because polyps can progress more rapidly to cancer in people with HNPCC, more frequent screening may also be recommended.
Inflammatory bowel disease — In people with Crohn's disease of the colon or with ulcerative colitis, the optimal screening plan will depend on the amount of colon inflamed by the disease and the duration of the disease. Screening usually entails colonoscopy once every one to two years beginning after eight years of disease in people with pancolitis (inflammation of the entire colon) or after 15 years in people with colitis only of the left-sided colon.
WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
...
REFERENCES
1. Mandel, JS, Bond, JH, Church, TR, et al. Reducing mortality from colorectal cancer by screening for fecal occult blood. Minnesota Colon Cancer Control Study. N Engl J Med 1993; 328:1365.
2. Selby, JV, Friedman, GD, Quesenberry, CP Jr, Weiss, NS. A case-control study of screening sigmoidoscopy and mortality from colorectal cancer. N Engl J Med 1992; 326:653.
3. Winawer, SJ, Flehinger, BJ, Schottenfeld, D, Miller, DG. Screening for colorectal cancer with fecal occult blood testing and sigmoidoscopy. J Natl Cancer Inst 1993; 85:1311.
4. Rex, DK, Cutler, CS, Lemmel, GT, et al. Colonoscopic miss rates of adenomas determined by back-to-back colonoscopies. Gastroenterology 1997; 112:24.
5. Winawer, SJ, Stewart, ET, Zauber, AG, et al. A comparison of colonoscopy and double-contrast barium enema for surveillance after polypectomy. National Polyp Study Work Group. N Engl J Med 2000; 342:1766.
Great info. Thanks, Rich. I suppose one other pc of info would useful:
what is the absolute value of the threat of colon cancer in the population being screened just for a routine physical (that is, a population not biased by suspicious symptoms). I suppose that might also be age dependent?
I heard a doctor on the radio discussing screening in general (not necessarily colon cancer). He was saying that if screening reduced the
threat by 50% but the threat itself was only 1 part per million, then the risk of doing the test could be higher than the disease. Of course if the
risk of the disease was 10% but screening reduced the threat to 5%, that would be quite different.
what is the absolute value of the threat of colon cancer in the population being screened just for a routine physical (that is, a population not biased by suspicious symptoms). I suppose that might also be age dependent?
I heard a doctor on the radio discussing screening in general (not necessarily colon cancer). He was saying that if screening reduced the
threat by 50% but the threat itself was only 1 part per million, then the risk of doing the test could be higher than the disease. Of course if the
risk of the disease was 10% but screening reduced the threat to 5%, that would be quite different.
