]]]]]]]]]]]]         BOWEL CANCER AND HEALTH RISKS        [[[[[[[[[[[[
                         From Newsletter of            (10/30/89)
                       Thomas A. Dorman, M.D. 
                        (Freeman 93401DORM)

       Cancers begin small, in one place, and grow. Later they 
spread. That is what usually happens. One of the reasons skin cancers 
are not such a bad thing is because we can see them when they start 
and do something. Cancers on the inside of the body are not easy to 
see. Nonetheless many of the cancers which affect the internal organs
begin on the lining of the food tube, which is called the gastero-
intestinal tract. It is not a very polite fact, but a medical one, 
that cancers of the lower end are more common than the upper. The 
bowel can be inspected, the cancers identified and removed before it 
is too late. It is also known that cancers in the bowel can bleed, and 
not surprisingly, large cancers which have grown from little cancers 
and therefore have been there longer are more likely to bleed more 
often and in larger amounts.
       First a question for which you do not need to be a doctor: If 
you wanted to see if the sky is cloudy would you look out of the 
window, or would you put your hand out to feel for rain?
       Now a question for which you need a very impressive medical 
degree: If you wanted to see if there was a cancer in the bowel would 
you look in there, or would you test for bleeding?
       Dorman's Law No 2.      When exhorted on scientific grounds to 
do the right thing, and when authority and statistics are quoted, look 
out for sleight of hand. Somebody is obscuring something. The profit 
and loss account might be a factor.
       Let us do a few rough calculations. The population over 45 
years old in the U.S. is 73,461 million. The cause of death is 325,000 
for heart disease, 191,700 for malignancies(1985 statistics). The 
expected incidence for colon cancers is 150,000, most of which occur 
in people over 60 years old. 40% of diagnosed bowel cancer cases are 
usually cured, which is the reaper's way of saying that death is 
postponed for another diagnosis. I am not being facetious when I put 
it this way, because Dorman's first law of medicine is that humans are 
mortal. Excuse me, but I just have to digress.
I have been in S.L.O. for a dozen years, and about a year after my 
arrival I was looking after a gentleman aged 102. Though he had been 
in hospital and had been given a number of medical labels, like heart 
disease, he was hale and hearty. There was nothing wrong with him. He 
was cheerful and bright and at times grumpy and tired. He died. There 
was no special illness, no complaint from his heart or anything else. 
Yours truly wrote on the death certificate that he died of old age. A 
cardinal mistake. My education began. The coroner asked politely. I 
was strong. He died of old age. But soon "Sacramento" called. They 
only asked: Dr. what is your licence number? Does the BMQA know about 
you yet? Which university did you come from? In America, Dr., everyone 
has a diagnosis! It didn't take long for the patient to have died of 
heart disease (on the certificate). Lesson: Officially we are 
immortal. 
       The law of certificates. 
       They have to look impressive and stick to the rules. Facts and 
common sense don't count. But let's go back to bowel cancers.
       It is estimated that occult blood test screening in the stool 
(like putting your hand out to see if it is raining) costs $2.50 per 
screen per year and will pick up about 2.25 cancers per thousand of 
population screened, in  a hitherto unscreened population. As most 
bowel cancers develop in individuals over 60, for the purpose of this 
little chat I will assume a retired population. The average money 
expended per person per year in America (for everything and that 
includes what you spend and what the governments spends on each human 
being) can perhaps be approximated by dividing the gross national 
product by the population P 3,947 billion for 239,283,000 = $14,565 
per person (1985 numbers). It is hard to predict the increase in life 
span from a cure of bowel cancer as a general average, but a 
reasonable assumption is 7 years. 40% cure of 150,000 cases represents 
60,000 cases a year to whom 7 years might be added. This is a best 
case scenario. Now assume non-productive life years; i.e., retired 
`years'. Next we should multiply the cost of these years, snatched 
from the reaper by their estimated total. 60,000 x  $14,565 = $6,117 
billion. This is the `cost' per annum. It is the national expenditure 
on non-productive American's life/years. Keep this little number in 
mind for a few more lines. The plot thickens. Now the average expense 
for a terminal cancer illness has been estimated at $21,200 for the 
last year of life, but we can't deduct this figure from the expense 
because everyone dies sometime. (The law of mortality). As an average, 
over the long haul, the death rate won't change, though the cause 
might. Everyone born to woman has to die! We will only find the same 
diagnoses in older people. That is a backwards way of saying people 
live longer. 
       So let's go back to looking at the cost of prevention again, 
in my analogy looking for rain versus feeling for it. Sigmoidoscopy 
finds cancers earlier. First of all we should remember that it rains 
when it rains and bowel cancers bleed when they bleed. Most bowel 
cancers are without symptoms until it is too late. We should also 
remember that the unimproved cure rate from colon cancer reflects just 
those reported as colon cancer, not those reported as colon polyps, 
with malignancy in situ. In any case reporting of cancerous polyps is 
incomplete.
       Assume sigmoidoscopy to 60cm @ $150, every three years in the 
population at risk over 45. That is 3,82 million sigmoidoscopies = 
$573 million per year. At best this expense will detect about 110,000 
cancers. (About 2 per thousand will develop cancer a year in the 
population over 45.) The screening cost P per cancer detected P is 
about $75,000. Given the 7 year addition to the life expectancy the 
life-expense, for those who got the extra years, will be $185,000. The 
national RloadS, not the good life - we are talking money and 
government controlled expense is $27 billion per annum. (Not all bowel 
cancers will be detected with sigmoidoscopy alone, assume an 80% 
detection rate.) An estimate for the decreased incidence of cancer 
after the first year of mass screening is in order in these 
calculations, because each cancer develops over about 4-5 years from a 
small polyp to a bad one. Against this we need to weigh the expense in 
screening the extra lives around. People who have had cancer are at 
increased risk for further cancer and screening every one to two years 
is recommended. Let us assume these numbers are about equal. We are 
left then with the following: For an 80% or better chance of 
prevention, i.e. early detection, you can spend $150 every four years 
for sigmoidoscopy. This will give you a 1/8 chance of increasing your 
life expectancy about 7 years and allowing you to spend an extra 
$75,000 for living expenses. If you rely on screening the cancers with 
bleeding when bleeding eventually occurs, i.e. later in the cancer's 
growth, you have a 40% chance of a cure. You are not likely to save 
money on your terminal illness as long as you are mortal. $27 billion 
per year spent on extra life and health costs represents 0.68% of the 
gross domestic product. Most cancers develop in the distal, or far 
down part, of the large bowel. A few develop higher up. To see them a 
longer instrument, a colonoscope, is needed. The test is more 
unpleasant and a tiny bit more risky. Barium enemas are also useful 
for detecting bowel cancer. In convenience and costs, the curve 
becomes exponential. In this practice your doctor has adopted the 
policy of recommending sigmoidoscopy every four years. Testing for 
occult blood in the stool is likely to pick up later and larger and 
more dangerous cancers - a second best. It is cheaper to the national 
exchequer. It would be cheapest, of course, if we all died on the day 
of retirement. In our civilization a doctor's responsibility is to his 
patients, their longevity and well-being. When the day comes that the 
doctor's responsibility is to the national exchequer - look out for 
the statistics.
       Here are the References:-
       The World in Figures; The Economist, 1986.
       Block, G.E. Colon cancer: diagnosis and prognosis in the 
elderly. Geriatrics; 1989 May.
       Enblad, P.; Adami, H.O.; Bergstrom, R.; Glimelius, B.; 
Krusemo, U.; Pahlman, L. Improved survival of patients with cancers of 
the colon and rectum? J Natl Cancer Inst; 1988 Jun 15.
       Eliakim, R.; Shabetai, O.; Rachmilewitz, D. Screening for 
fecal occult blood in Israel. Different approaches to recruitment. J 
Clin Gastroenterol; 1988 Apr.
       Long, S.H.; Gibbs, J.O.; Crozier, J.P.; Cooper, D.I. Jr; 
Newman, J.F. Jr; Larsen, A.M. Medical expenditures of terminal cancer 
patients during the last year of life. Inquiry.; 1984 Winter.
       Ayiomamitis, A. The epidemiology of malignant neoplasms of the 
large intestine in Canada: 1941-1985. J Clin Gastroenterol; 1989 Feb.
       Olsen, H.W.; Lawrence, W.A.; Snook, C.W.; Mutch, W.M. Risk 
factors and screening techniques in 500 patients with benign and 
malignant colon polyps. An urban community experience. Dis Colon 
Rectum; 1988 Mar.

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