NEW YORK, Dec. 16, 2008

Study Shows Limitations Of Colonoscopies

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(CBS)  Colonoscopies have long been considered the gold standard for colorectal cancer screening - 90 percent effective in detecting the second leading cancer killer of men and women in this country.

But a new Canadian study suggests the procedure may detect polyps and early cancers only 60 to 70 percent of the time , reports CBS News medical correspondent Dr. Jon LaPook.

According to the study, whether a colonoscopy saves a life may depend on exactly where in the colon the cancer starts

"It seemed to prevent two-thirds of the deaths from left sided colon cancer," said Dr. Nancy Baxter of the University of Toronto. "But it didn't seem to prevent any of the deaths from right-sided colon cancer."

One possible explanation is that polyps on the left side of the colon are more likely to be raised and easy to detect, while those on the right side tend to be flatter and easy to miss.

The results are being debated by doctors. Only about 30 percent of the colonoscopies in this Canadian study were performed by gastroenterologists.

"We don't know the quality of the colonoscopies, the skill of the examiners, the preparation of the patients, the completeness of the colonoscopies," warned Dr. Sidney Winawer of the Memorial Sloan-Kettering Cancer Center.

Other studies have found doctors who rush through the procedure can miss polyps. It's also important for patients to follow the instructions for colon cleansing to the letter.

And even if colonoscopies are less accurate than previously thought, they're still the best way to prevent colon cancer.

"Colonoscopy can reduce mortality from colon cancer," Winawer said.

Colon cancer screenings are recommended for most people starting at age 50. Patients should choose experienced doctors and make sure that they follow their doctors' directions to the letter when preparing for the procedure.

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Add a Comment See all 18 Comments
by brainteaser2 December 18, 2008 9:22 PM EST
Colonoscopies are fine - the hard part to figure out is why they have become so expensive. The procedure is basically a med school skill level. A few simple and inexpensive drugs are used so why the big bucks??? We need to take the hot air out of many medical procedures so they are affordable.
Reply to this comment
by godofredo29 December 18, 2008 2:44 PM EST
What part of "minimally invasive" do these doctors not understand? We men are already familiar with this song and dance with cystoscopies (where the doctor forces a large probe up your ***). They want more people to have colonoscopies? Then make them safer and easier! And, by safer, I mean no waking up after one of these only to discover you''ve had a colostomy because the probe pierced your colon and you had to have part of it removed. And, it surely has to be possible to effectively cleanse the colon without the draconian tactics they use now. "Make it pleasant and they will come!"
Reply to this comment
by liptonlight December 17, 2008 6:14 PM EST
It''s easier to die than to take MoviPrep
Reply to this comment
by mitch5511 December 17, 2008 4:09 PM EST
MRIs are better!
Reply to this comment
by saraplumber December 17, 2008 3:14 PM EST
But to answer your question, I have already instructed and presented my family with a living will. I am DNR, no feeding tubes, no intubation, no life saving attempts. Keep me comfortable and let me go to the maker.

How much $$ do you want your children giving to saving your life instead of leaving it for them/

Posted by docpeter1953 at 10:57 AM : Dec 17, 2008
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I wasn''t talking about unnecessary or not useful live saving measures. Many chronic diseases (i.e. diabetes) can be treated with medications - medications which are costly. Or, what happens if you develop a tear in your aorta; an expensive surgical procedure can be performed which will save your life.

I don''t know the answer; there are always trade-offs involved. The latest treatments and procedures are going to be expensive. So, the trade-off may be between offering access to the best, most high-tech care, or offering affordable care to everyone.
Reply to this comment
by j_flood December 17, 2008 2:38 PM EST
Please stop quibbling about the health care systems and focus on the need to have colonoscopies!

Had one two weeks ago - they found a small tumor in the notorious ''right'' side and I''m in for surgery on the 19th.

Please focus your comments on the value of colonoscopies not on salient comments.
Reply to this comment
by docpeter1953 December 17, 2008 1:57 PM EST
Seriously though, let''''''''''''''''s worry about getting adequate health care for all Americans instead of advanced care for those who can afford it.

Posted by gce65 at 03:39 AM : Dec 17, 2008
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Are you sure about this? What happens if you get stricken with an orphan disease that requires lifelong, expensive medication? Or need an expensive procedure to repair your heart?

Posted by saraplumber at 09:35 AM : Dec 17, 2008
____________________

Sorry, had a computer hiccough.

But to answer your question, I have already instructed and presented my family with a living will. I am DNR, no feeding tubes, no intubation, no life saving attempts. Keep me comfortable and let me go to the maker.

How much $$ do you want your children giving to saving your life instead of leaving it for them/
Reply to this comment
by docpeter1953 December 17, 2008 1:53 PM EST
Seriously though, let''''''''s worry about getting adequate health care for all Americans instead of advanced care for those who can afford it.

Posted by gce65 at 03:39 AM : Dec 17, 2008
----------------
Are you sure about this? What happens if you get stricken with an orphan disease that requires lifelong, expensive medication? Or need an expensive procedure to repair your heart?

Posted by saraplumber at 09:35 AM : Dec 17, 2008
Reply to this comment
by docpeter1953 December 17, 2008 1:50 PM EST
From the above article, ''But a new Canadian study suggests the procedure may detect polyps and early cancers only 60 to 70 percent of the time ... Only about 30 percent of the colonoscopies in this Canadian study were performed by gastroenterologists.''
_______________________

Can we say ''correlation'' here? It would seem evident that, if, 30% of doctors performing colonoscopies were NOT trained to do so it would account for the 60% - 70% of detecting early CA and polyps. Looks like the MDs covering each other''s a$$es.
Reply to this comment
by docpeter1953 December 17, 2008 1:45 PM EST
Why would anyone expect a Gold Standard in colonoscopies. This profit driven industry that is control by the physicians that control the tests may be beyond fixing. It reminds me of the boxing industry, it can not be clean up.

Posted by baileycc at 09:38 AM : Dec 17, 2008
__________________________

I do hope you are not really serious. Colonoscopies are a better predictor of CA than MRI or Barium enemas, or CT scans. With colonscopies the polyps are visually viewed and removed, sent to a lab for dissection and evaluation for CA -no, not polyps are malignant. MRI and CT cannot do this prodedure. Also, thgere are many times when something is read as ''normal'' when in fact there is something there.
Reply to this comment
by December 17, 2008 12:38 PM EST
Why would anyone expect a Gold Standard in colonoscopies. This profit driven industry that is control by the physicians that control the tests may be beyond fixing. It reminds me of the boxing industry, it can not be clean up.
Reply to this comment
by saraplumber December 17, 2008 12:35 PM EST
Seriously though, let''''s worry about getting adequate health care for all Americans instead of advanced care for those who can afford it.

Posted by gce65 at 03:39 AM : Dec 17, 2008
----------------
Are you sure about this? What happens if you get stricken with an orphan disease that requires lifelong, expensive medication? Or need an expensive procedure to repair your heart?
Reply to this comment
by saraplumber December 17, 2008 12:32 PM EST
Only about 30 percent of the colonoscopies in this Canadian study were performed by gastroenterologists.
------------
Who the heck was performing these colonoscopies, then? The local auto mechanic?
Reply to this comment
by perrycbs1 December 17, 2008 12:24 PM EST
Many people who have insurance coverage in the US "refuse" to have this test done. I recently had my first inspection which led to a lot of discussions among people I know. I estimate between 1/3 and 1/2 of the people I have talked with have decided not to do this procedure.

I also know that the hospital does a certain number of these procedures on people without health insurance. Of course, they can''t do all people without insurance.

Overall - makes me really wonder how effective this procedure is in reducing the cancer rate in the US. Obviously - it does wonders for those who use it. But, more people will die early than what easily could be.

Reply to this comment
by mtminds December 17, 2008 8:23 AM EST
Good point. Compared to other "modern" nations, the US has the highest number of citizens that cannot afford any health care.
Reply to this comment
by gce65 December 17, 2008 6:39 AM EST
Seriously though, let''s worry about getting adequate health care for all Americans instead of advanced care for those who can afford it.

We''re the only industrialized nation in the world that treats our health care as a for-profit business, a model that has failed miserably.
Reply to this comment
by gce65 December 17, 2008 6:35 AM EST
Colonoscopies are limited? I thought they could see well past Uranus! :)
Reply to this comment
by rhs648 December 17, 2008 12:36 AM EST
Only 30% of the procedures were performed by gastroenterologists. Is this the result of the Canadian socialized medicine? If so, we need to carefully think about whether we want universal health care controlled by the government. I have a PPO rather than an HMO. HMOs may be fine for the masses but is not good enough for my family. We do not want a plan that requires us to see certain doctors or requires permission to see a specialist.
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