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Cancer
is a dreaded disease and the lay man is being bombarded
with all sorts of information about this disease. There
seems to be a widespread feeling that in case of cancers small
equals early. There is a pressure on healthy people
to get themselves regularly screened for cancer, in the
fond hope that if they did that they could discover early
lesions which are small and, are therefore, curable. As I
have written time and again that in a dynamic system like
the human body this type of linear relationship does not
hold good. Now we have an important study in the leading
British medical journal, The Lancet, about the screening
for breast cancer, which should be given wide publicity
to the lay public.
Breast cancer is made out to be a nightmare for all
women. It is said to be a devastating disease.There have
been even suggestions that women after the age of thirty
or so, having finished with the biological need for their
breasts, should get them removed and replaced by
beautiful prostheses, to avoid future cancers. I wish the
human body worked according to our whims and fancies.
The truth is that women have a higher chance of getting
heart attacks than breast cancers. Coronary heart
disease in women has not been properly documented and has
always been under-diagnosed and under-investigated.
Recent data suggest that women get as many heart attacks
as men and they may have a more severe course of the
disease.
Many people think that the best bet for a cure in breast
cancer is early diagnosis. Mammography has the capacity
to detect small lesions in the breast ( which may be
cancer ) at an early pre-symptomatic stage. One of the
studies ( Breast Cancer Detection Demonstration Project )
did show that 0.5% of the 2,50,000 women screened did
show early cancer. This was advertised by the media and
the vested interests as proof of benefit to humanity. The
million dollar question is if this kind of putative
diagnosis benefits patients in terms of overall
longevity!
Despite this fact the results were being advertised by
the media and television in America thus:
- Most women with
breast cancer could be saved by
detection....with mammography.
- Mammography helps
your doctor see breast cancer before there is a
lump when the cure rate is 100%.
- If you are over 35
and haven’t had a mammogram, you need more
than your breasts examined.
All the above
advertisement are wishful thinking. Statements
like the above have raised public awareness resulting in
a clamour for mammography requests. There have been sane
advice, even in America, by thinking doctors for more
caution in this regard, but the latter has mostly been
ignored by the media and never reached their targets.
There are very disturbing issues involved in this and a
recent large study, in addition to many smaller studies,
has drawn our attention to the potential hazards of this
luxury.
When analysed in terms of population benefits, the three
important studies showed that to save one woman
from breast cancer per year we have to screen 7086 women
unnecessarily ( Health Insurance Plan of NewYork ), or
63,264 women unnecessarily ( MALMO Study), or all the
population in a country ( infinity) according to the
Canadian Breast Cancer Screening Study. These figures
give us an idea of the foolishness of this screening
procedure.
In addition the last study quoted above gave the
following startling figures:
- 5% of the mammograms
are positive or suspicious.
- Of the positive
people 80-93% were false positives. This caused
much unnecessary anxiety and even surgical
removal of the normal breasts.
- 11% of the screenings
were false negative. They showed a normal scan
when there was a cancer already there and this
gave the patients a false sense of happiness
while the cancer could grow unimpeded.
- The annual cost of one
single life saved was around $ 1.2 million
and Sterling pounds 5,58,000 or in Indian Rupees
3 crores. How many countries in this world can
afford this?
The study concluded "
In the allocation of limited resources, public health
policy on a proposed mass population intervention must be
based on a critical analysis of the benefits, harm, and
the cost. Since the benefit achieved is marginal, the
harm caused is substantial, and the costs incurred are
enormous, we suggest that public funding for breast
cancer screening in any age group is not
justifiable." ( emphasis mine).
In fact another study of the audit of mammography in
Sweden had shown more damaging results than the Canadian
study reported above. I hope our medical men and women
wake up to critically appraise many of these methods
before we do more damage to our people. None of the
screening methods will have any useful role to play in
either predicting the future events in a man’s life
or even in avoiding what are called the avoidable deaths.
The only avoidable deaths that I know of are traffic
accident deaths, about which the society seems to do very
little.
Let our politicians try and give people clean drinking
water and enough food to eat and, if possible, avenues
for earning their daily bread. Diseases will look after
themselves if we can avoid the two most important risk
factors, tobacco smoke and alcohol. The latter are the
darlings of our leaders and one can hope to have them
with us always! God save mankind on this planet. The
medical politicians will want the hi-tech screening
methods even in remote hospitals. ( Wright CJ, Mueller
CB., Lancet 1995;346:29-32.)
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