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By Dr. Samuel Epstein
The updated Federal guidelines,
announced by Health and Human Services Secretary Tommy Thompson on February
21, strongly recommending annual mammography for women over the age of
40, are unlikely to resolve the current headline debate.
The guidelines, surprisingly
based on an unpublished analysis by an independent advisory board, ignore
evidence on the risks of breast cancer from mammography. Furthermore,
they dismiss evidence on the effectiveness of breast self examination
(BSE) combined with annual clinical breast examination (CBE).
Screening mammography poses significant and cumulative risks of radiation,
particularly for premenopausal women, of which women remain uninformed.
The routine practice of taking four films of each breast annually results
in approximately 1 rad (radiation absorbed dose) exposure.
This is about 1,000 times
greater than exposure from a chest x-ray which
is broadly focused on the entire chest rather than narrowly on the breast.
The premenopausal breast is highly sensitive to radiation, each 1 rad
exposure increasing breast cancer risk by about 1 percent, with a cumulative
10 percent increased risk for each breast over a decade's screening.
Radiation risks are further
increased, by some four-fold, for the 1 to 2 percent of women who are
unknowing silent carriers of the A-T (ataxia-telangiectasia) gene. By
some estimates, this accounts for up to 20 percent of all breast cancers
diagnosed annually. All these risks are greater for women in their thirties
who are being encouraged to undergo "baseline screening," for
which there is no evidence of any future relevance.
Since 1928, physicians have been warned to handle "cancerous breasts
with care -- for fear of accidentally disseminating cells" and spreading
the cancer. Nevertheless, mammography entails tight and often painful
breast compression, particularly in premenopausal women. This may lead
to distant and lethal spread of malignant cells by rupturing small blood
vessels in or around small undetected breast cancers.
Another serious danger of mammography is the fact that mammography centers
are being overbooked as a result of aggressive promotion of premenopausal
screening. Resultingly, patients referred for diagnostic mammography,
because of suspicious clinical or other findings, are now experiencing
potentially life-threatening delays, of up to several months, before they
can be examined.
The advisory panel's dismissal of BSE and CBE is inconsistent with the
results of a September 2000 publication by leading University of Toronto
epidemiologists.
Based on a unique individually
randomized control trial on breast cancer mortality in some 40,000 women,
it was concluded that monthly BSE following brief training coupled with
annual CBE by a trained health care professional is a least as effective
as screening mammography in detecting small tumors.
National networks of BSE and
CBE clinics staffed by trained nurses should be established to replace
screening mammography. Apart from their minimal costs, such clinics would
empower women and free them from increasing dependence on industrialized
medicine and complicit medical institutions.
It should further be pointed out that the new Federal guidelines ignore
the growing and inflationary costs of mammography. Screening all premenopausal
women, some 20 million annually, would cost about $2.5
billion, about 14 percent of estimated Medicare spending on
prescription drugs.
These costs would be increased
some four-fold if the highly profitable machine and film industries succeed
in replacing film machines, costing about $100,000 each, with the latest
high-tech digital machines costing about $400,000 each. These have been
recently approved by the FDA although there is no evidence of improved
effectiveness.
Finally, it may be noted
that no nation other than the U.S. recommends routine screening of premenopausal
women.
Samuel S. Epstein, M.D.
Professor Emeritus Environmental Medicine
University of Illinois at Chicago School of Public Health
and Chairman, Cancer
Prevention Coalition
Published in the LA
Times February 25, 2002
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