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The National Breast Cancer Coalition (NBCC) is Urged by Dr. Samuel
Epstein to Consider Breast Examination as a Practical Alternative
to Mammography
Chicago, 5/03/01. The NBCC's recommendations
against premenopausal mammography will be confirmed and extended
by leading epidemiologists
at its tenth anniversary May 5-9 Washington, D.C. meeting. However,
consideration should also be given to promoting the role of breast
examination as an effective and safe alternative to screening.
Dr. Anthony Miller, co-investigator of the recent
Canadian National Breast Cancer Screening Study, will report on
a unique trial of
some 39,000 postmenopausal women. Half performed monthly breast
self examination (BSE) following instruction by trained nurses,
had annual clinical breast examinations (CBE) by trained professionals,
and also had annual mammograms. The other half practiced BSE and
had annual CBE's but no mammograms; it may be noted that CBE performance
by trained nurses was as good, if not better, than the study surgeons.
Dr. Miller concluded: "The addition of annual mammography
to physical examination has no impact on breast cancer mortality".
Thus, mammographic detection of non-palpable cancers failed to
improve survival rates.
Dr. Peter Gotzsche will further challenge
claims that screening reduces breast cancer mortality by enabling
early detection and
treatment. Based on recent analysis of two large Swedish trials,
he concluded: "There is no reliable evidence that screening
decreases breast cancer mortality--(and thus that) screening is
unjustified".
As detailed in a review, in press in the International
Journal of Health Services, by Dr. Samuel Epstein, Dr. Rosalie
Bertell,
and Barbara Seaman, reservations on the efficacy, besides hazards,
of screening are further stressed by the following considerations:
- Mammography is not a technique for early diagnosis of breast
cancer which is rarely detectable until about eight years old.
Screening
should thus be recognized as damage control rather than, misleadingly,
as "secondary prevention".
- Missed cancers are common
in premenopausal women due to their dense breast structure, and
also in postmenopausal women on estrogen
replacement therapy who often develop breast densities, making
their mammograms difficult to read. Also, about one third of
all cancers, and more of the aggressive premenopausal cancers, are
diagnosed between annual screenings. Women can thus be lulled
into a false sense of security by an apparently negative mammogram.
- Misdiagnosed
cancers are common in premenopausal women, postmenopausal women
on estrogen replacement therapy, and women with a strong
family history, and can reach 100% over a decade's screening.
Misdiagnoses thus result in anxiety, more mammograms, unnecessary biopsies
and even mastectomies.
- Overdiagnosis with subsequent overtreatment
are among the major
risks of mammography. With increased screening, pre-invasive
breast duct cancer or ductal carcinoma-in-situ (DCIS), is now diagnosed
in some 40,000 women annually and unnecessarily treated as
invasive cancer by lumpectomy plus radiation or even mastectomy. However,
most DCIS never becomes invasive even if untreated, and mortality
is low, 1%, whether diagnosed and treated early or late.
- Screening poses cumulative cancer risks. Contrary to assurances
that radiation exposure is trivial, the routine of taking four
breast films results in 1 rad (radiation absorbed dose) exposure,
in contrast to about one thousandth less for a chest x-ray.
The premenopausal breast is highly sensitive to radiation, each
rad
exposure increasing cancer risk by 1%, resulting in a cumulative
10% increased risk over 10 years screening; risks are greater
for "baseline" screening
at younger ages. Risks are even higher for silent carriers
of the A-T gene, accounting for up to 20% of all cancers. Less
recognized
dangers are due to the often painful breast compression during
premenopausal mammography. This may rupture blood vessels in
or
around small undetected cancers with resulting lethal spread
of malignant cells.
- Concerns on the unreliability, besides
dangers, of premenopausal screening are so pervasive that this
practice remains unique
to the U.S.
- Screening poses an inflationary threat; average Medicare
and insurance costs are $70 and $125, respectively. If all 20
million premenopausal
women had annual mammograms, minimal costs would be $2.5
billion. These costs would be quadrupled if the industry succeeds
in
replacing film machines, costing about $100,000, by digital machines, costing
about $400,000, for which there is no evidence of improved
effectiveness.
Breast examination, CBE combined with BSE, is effective, safe
and low in cost in striking contrast with mammography. The
American Cancer Society (ACS) admitted in 1985 that "at
least 90% of the women who develop breast carcinoma discover
the tumor themselves".
Nevertheless, the ACS, National Cancer Institute, American
College of Radiology, and the mammography industry, all remain
dismissive
of breast examination. Claims for the benefits of mammography
screening at all ages, in a non-peer reviewed ACS publication
in the May
issue of Cancer, are highly flawed including by "before-after" comparisons
of women unstratified by menopausal status.
National networks of CBE and BSE clinics staffed
by trained nurses should be established. These clinics could further
empower women
by providing them with scientific information on breast
cancer
prevention of which women still remain largely unaware.
CONTACT:
Samuel S. Epstein, M.D.
Professor
emeritus Environmental and Occupational Medicine
Chairman,
Cancer Prevention Coalition
University
of Illinois at Chicago
School
of Public Health, M/C 922
2121
W. Taylor Street
Chicago,
IL 60612
phone
312-996-2297
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