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Mammography Article by Samuel Epstein, MD
Danger and Unreliability of Mammography
Breast Examination is a Safe, Effective, and Practical Alternative
by Samuel S. Epstein , Rosalie Bertell, Ph.D., GNSH and Barbara Seaman
Published in International Journal of Health Services, Volume 31, Number 3, Pages
605-615, 2001 Baywood Publishing Co., Inc.
Mammography screening is a profit-driven technology posing risks compounded by
unreliability. In striking contrast, annual clinical breast examination (CBE) by a trained
health professional, together with monthly breast self-examination (BSE), is safe, at
least as effective, and low in cost. International programs for training nurses how to
perform CBE and teach BSE are critical and overdue.
Contrary to popular belief and assurances by the U.S. media and the cancer
establishment--the National Cancer Institute (NCI) and American Cancer Society
(ACS)--mammography is not a technique for early diagnosis. In fact, a breast cancer
has usually been present for about eight years before it can finally be detected.
Furthermore, screening should be recognized as damage control, rather than
misleadingly as ««secondary prevention.
DANGERS OF SCREENING MAMMOGRAPHY
Mammography poses a wide range of risks of which women worldwide still remain
uninformed.
Radiation Risks
Radiation from routine mammography poses significant cumulative risks of initiating
and promoting breast cancer (1-3). Contrary to conventional assurances that radiation
exposure from mammography is trivial--and similar to that from a chest X-ray or
spending one week in Denver, about 1/1,000 of a rad (radiation-absorbed dose)--the
routine practice of taking four films for each breast results in some 1,000-fold greater
exposure, 1 rad, focused on each breast rather than the entire chest (2). Thus,
premenopausal women undergoing annual screening over a ten-year period are
exposed to a total of about 10 rads for each breast. As emphasized some three
decades ago, the premenopausal breast is highly sensitive to radiation, each rad of
exposure increasing breast cancer risk by 1 percent, resulting in a cumulative 10
percent increased risk over ten years of premenopausal screening, usually from ages
40 to 50 (4); risks are even greater for ««baseline»» screening at younger ages, for
which there is no evidence of any future relevance. Furthermore, breast cancer risks
from mammography are up to fourfold higher for the 1 to 2 percent of women who are
silent carriers of the A-T (ataxia-telangiectasia) gene and thus highly sensitive to the
carcinogenic effects of radiation (5); by some estimates this accounts for up to 20
percent of all breast cancers annually in the United States (6).
Cancer Risks from Breast Compression
As early as 1928, physicians were warned to handle ««cancerous breasts with care--
for fear of accidentally disseminating cells»» and spreading cancer (7). Nevertheless,
mammography entails tight and often painful compression of the breast, particularly
in premenopausal women. This may lead to distant and lethal spread of malignant
cells by rupturing small blood vessels in or around small, as yet undetected breast
cancers (8).
Delays in Diagnostic Mammography
As increasing numbers of premenopausal women are responding to the ACS's
aggressively promoted screening, imaging centers are becoming flooded and
overwhelmed. Resultingly, patients referred for diagnostic mammography are now
experiencing potentially dangerous delays, up to several months, before they can be
examined (9).
UNRELIABILITY OF MAMMOGRAPHY
Falsely Negative Mammograms
Missed cancers are particularly common in premenopausal women owing to the dense
and highly glandular structure of their breasts and increased proliferation late in their
menstrual cycle (10, 11). Missed cancers are also common in post-menopausal
women on estrogen replacement therapy, as about 20 percent develop breast
densities that make their mammograms as difficult to read as those of premenopausal
women (12).
Interval Cancers
About one-third of all cancers--and more still of premenopausal cancers, which are
aggressive, even to the extent of doubling in size in one month, and more likely to
metastasize--are diagnosed in the interval between successive annual mammograms
(2, 13). Premenopausal women, particularly, can thus be lulled into a false sense of
security by a supposedly negative result on an annual mammogram and fail to seek
medical advice.
Falsely Positive Mammogram
Mistakenly diagnosed cancers are particularly common in premenopausal women, and
also in postmenopausal women on estrogen replacement therapy, resulting in
needless anxiety, more mammograms, and unnecessary biopsies (14, 15). For women
with multiple high-risk factors, including a strong family history, prolonged use of the
contraceptive pill, early menarche, and nulliparity--just those groups that are most
strongly urged to have annual mammograms--the cumulative risk of false positives
increases to ««as high as 100 percent»» over a decade's screening (16).
Overdiagnosis
Overdiagnosis and subsequent overtreatment are among the major risks of
mammography. The widespread and virtually unchallenged acceptance of screening
has resulted in a dramatic increase in the diagnosis of ductal carcinoma-in-situ (DCIS),
a pre-invasive cancer, with a current estimated incidence of about 40,000 annually.
DCIS is usually recognized as micro-calcifications and generally treated by
lumpectomy plus radiation or even mastectomy and chemotherapy (17). However,
some 80 percent of all DCIS never become invasive even if left untreated (18).
Furthermore, the breast cancer mortality from DCIS is the same-- about 1 percent--
both for women diagnosed and treated early and for those diagnosed later following
the development of invasive cancer (17). That early detection of DCIS does not reduce
mortality is further confirmed by the 13-year follow-up results of the Canadian National
Breast Cancer Screening Study (19). Nevertheless, as recently stressed, ««the public
is much less informed about overdiagnosis than false positive results. In a recent
nationwide survey of women, 99 percent of respondents were aware of the possibility
of false positive results from mammography, but only 6 percent were aware of either
DCIS by name or the fact that mammography could detect a form of `cancer' that often
doesn't progress»» (20).
Quality Control
In 1992 Congress passed the National Mammography Standards Quality Assurance
Act requiring the Food and Drug Administration (FDA) to ensure that screening centers
review their results and performance: collect data on biopsy outcomes and match them
with the original radiologist's interpretation of the films (21). However, the centers do
not release these data because the Act does not require them to do so. It is essential
that this information now be made fully public so that concerns about the reliability of
mammography can be further evaluated. Activist breast cancer groups would most
likely strongly support, if not help to initiate, such overdue action by the FDA.
FAILURE TO REDUCE BREAST CANCER MORTALITY
Despite the long-standing claims, the evidence that routine mammography screening
allows early detection and treatment of breast cancer, thereby reducing mortality, is at
best highly questionable. In fact, ««the overwhelming majority of breast cancers are
unaffected by early detection, either because they are aggressive or slow growing»»
(21). There is supportive evidence that the major variable predicting survival is
««biological determinism--a combination of the virulence of the individual tumor plus
the host's immune response,»» rather than just early detection (22).
Claims for the benefit of screening mammography in reducing breast cancer mortality
are based on eight international controlled trials involving about 500,000 women (23).
However, recent meta-analysis of these trials revealed that only two, based on 66,000
postmenopausal women, were adequately randomized to allow statistically valid
conclusions (23). Based on these two trials, the authors concluded that ««there is no
reliable evidence that screening decreases breast cancer mortality--not even a
tendency towards an effect.»» Accordingly, the authors concluded that there is no
longer any justification for screening mammography; further evidence for this
conclusion will be detailed at the May 6, 2001, annual meeting of the National Breast
Cancer Coalition in Washington, D.C., and published in the July report of the Nordic
Cochrane Centre.
Even assuming that high quality screening of a population of women between the ages
of 50 and 69 would reduce breast cancer mortality by up to 25 percent, yielding a
reduced relative risk of 0.75, the chances of any individual woman benefiting are
remote (18). For women in this age group, about 4 percent are likely to develop breast
cancer annually, about one in four of whom, or 1 percent overall, will die from this
disease. Thus, the 0.75 relative risk applies to this 1 percent, so 99.75 percent of the
women screened are unlikely to benefit.
THE UNITED STATES VERSUS OTHER NATIONS
No nation other than the United States routinely screens premenopausal women by
mammography. In this context, it may be noted that the January 1997 National
Institutes of Health Consensus Conference recommended against premenopausal
screening (24), a decision that the NCI, but not the ACS, accepted (4). However, under
pressure from Congress and the ACS, the NCI reversed its decision some three
months later in favor of premenopausal screening. The U.S. overkill extends to the
standard practice of taking two or more mammograms per breast annually in
postmenopausal women. This contrasts with the more restrained European practice
of a single view every two to three years (4).
BREAST EXAMINATION IS A SAFE AND EFFECTIVE ALTERNATIVE TO
MAMMOGRAPHY
That most breast cancers are first recognized by women themselves was admitted in
1985 by the ACS, an aggressive advocate of routine mammography for all women
over the age of 40: ««We must keep in mind the fact that at least 90 percent of the
women who develop breast carcinoma discover the tumors themselves»» (25).
Furthermore, as previously shown, ««training increases reported breast self-
examination frequency, confidence, and the number of small tumors found»» (26).
A pooled analysis of several 1993 studies showed that women who regularly
performed BSE detected their cancers much earlier and with fewer positives nodes
and smaller tumors than women failing to examine themselves (27); BSE would also
enhance earlier detection of missed or interval cancers, especially in pre-menopausal
women (28). There is a strong consensus that the effectiveness of BSE critically
depends on careful training by skilled professionals, and that confidence in BSE is
enhanced with annual CBEs by an experienced professional using structured
individual training (29). The tactile sensitivity of BSE can be increased by the use of
Mammacare techniques to enhance lump detection skills (30, 31), and by the use of
FDA-approved and nonprescription thin and pliable lubricant-filled sensor pads (32,
33).
In a joint U.S. and Chinese large-scale trial based on 520 Chinese factories, women
in half the factories were trained in and practiced BSE, while the other group of women
served as controls (34). The five-year follow up results reported no reduction in breast
cancer mortality in women in the BSE group. However, these findings are of little, if
any, significance in view of the minimum of a 10- to 13-year period required before the
efficacy of mammography is claimed to occur in premenopausal women (24),
especially as some of the trial's participants were in their thirties (28).
The critical importance and reliability of CBE has been strikingly confirmed by the
recent Canadian National Breast Cancer Screening Study (19). This reported the
results of a unique individually randomized controlled trial on some 40,000 women,
aged 50 to 59 on entry, followed by record linkage for nine to 13 years, with active
follow-up of cancer patients for an additional three years. Half the women performed
monthly BSE, following instruction by trained nurses, had annual CBEs (taking
approximately ten minutes) by trained nurses, and had annual mammograms, while
the other half practiced BSE and had annual CBEs but no mammograms. It should be
noted that the CBE performance by trained nurses had been shown to be as good as,
if not better than, that of the study surgeons (35), a finding of particular interest in view
of the growing perception among women that professional women are more sensitive
than men to women's health issues (36). The results of this study provide clear
evidence on the reliability of CBE, in association with BSE (19): ««In women age 50-59
years, the addition of annual mammography screening to physical examination has no
impact on breast cancer mortality.»» In other words, the mammographic detection of
nonpalpable cancers failed to improve survival rates, as ««the majority of the small
cancers detected by mammography represent pseudo-disease or overdiagnosis»»
(37); confirmation of this explanation awaits a trial, a protocol of which is available,
comparing mammography alone with physical examination alone. It should further be
noted that the mammogram group had a three-fold increase in the number of false
positives compared with the CBE and BSE group, resulting in unnecessary biopsies.
The effectiveness of CBE is further supported by the results of a new Japanese mass
screening study (38). Breast cancer mortality was compared in municipalities with or
without ««high coverage»» by CBE. The age-adjusted breast cancer mortality between
1986-1990 and 1991-1995 was reduced by over 40 percent in ««high coverage»»
municipalities, in contrast to only 3 percent in controls.
In spite of such evidence, the ACS and radiologists persist in their dismissiveness of
CBE and BSE, particularly as ««a substitute for screening practices that have a
`proven' benefit such as mammograms»» (33). The NCI no longer prints a BSE guide
in its breast cancer booklet, claiming that ««no studies have clearly shown a benefit
of using BSE»»; similarly, the ACS no longer distributes information on BSE, such as
shower-hanger cards.
There are immediate needs for a large-scale crash program for training nurses in how
to perform annual CBE and how to teach BSE. This need is critical for underinsured
and uninsured low-socioeconomic and ethnic women in the United States, and even
more so for developing countries. Once well trained, women of all social and cultural
classes could perform monthly BSE, at no cost or risk apart from false positives, which
decrease with increasing practice, along with annual CBE screening. Clinics offering
CBE and training in BSE could be established nationwide, and eventually worldwide,
in a network of clinics, community hospitals, churches, synagogues, and mosques.
These clinics could also act as a comprehensive source of reliable information on how
to reduce the risks of breast cancer, about which women still remain largely
uninformed by the cancer establishment (2). Besides lifestyle and reproductive risk
factors, emphasis should be directed to the massive overprescription of carcinogenic
hormonal drugs and the avoidable and involuntary exposures to petrochemical and
radionuclear carcinogens in the totality of the environment (39-41).
COSTS OF SCREENING
The dangers and unreliability of mammography screening are compounded by its
growing and inflationary costs; Medicare and insurance average costs are $70 and
$125, respectively. Inadequate Medicare reimbursement rates are now prompting
fewer hospitals and clinics to offer mammograms, and deterring young doctors from
becoming radiologists. Accordingly, Senators Charles Schumer (D-NY) and Tom
Harkin (D-IA) are introducing legislation to raise Medicare reimbursement to $100 (42).
If all U.S. premenopausal women, about 20 million according to the Census Bureau,
submitted to annual mammograms, minimal annual costs would be $2.5 billion (4).
These costs would be increased to $10 billion, about 5 percent of the $200 billion 2001
Medicare budget, if all postmenopausal women were also screened annually, or about
14 percent of the estimated Medicare spending on prescription drugs. Such costs will
further increase some fourfold if the industry, enthusiastically supported by
radiologists, succeeds in its efforts to replace film machines, costing about $100,000,
with the latest high-tech digital machines, approved by the FDA in November 2000,
costing about $400,000. Screening mammography thus poses major threats to the
financially strained Medicare system. Inflationary costs apart, there is no evidence of
the greater effectiveness of digital than film mammography (43), as confirmed by a
study reported at the November 2000 annual meeting of the Radiological Society of
North America (44). In fact, digital mammography is likely to result in the increased
diagnosis of DCIS.
The comparative cost of CBE and mammography in the 1992 Canadian Breast Cancer
Screening Study was reported to be 1 to 3 (45). However, this ratio ignores thehigh
costs of capital items including buildings, equipment, and mobile vans, let alone the
much greater hidden costs of unnecessary biopsies, specialized staff training, and
programs for quality control and professional accreditation (46). This ratio could be
even more favorable for CBE and BSE instruction if both were conducted by trained
nurses. The excessive costs of mammography screening should be diverted away
from industry to breast cancer prevention and other women's health programs.
CONFLICTS OF INTEREST
The ACS has close connections to the mammography industry (39). Five radiologists
have served as ACS presidents, and in its every move, the ACS promotes the interests
of the major manufacturers of mammogram machines and films, including Siemens,
DuPont, General Electric, Eastman Kodak, and Piker. The mammography industry
also conducts research for the ACS and its grantees, serves on advisory boards, and
donates considerable funds. DuPont also: is a substantial backer of the ACS Breast
Health Awareness Program; sponsors television shows and other media productions
touting mammography; produces advertising, promotional, and information literature
for hospitals, clinics, medical organizations, and doctors; produces educational films;
and, of course, lobbies Congress for legislation promoting availability of
mammography services. In virtually all its important actions, the ACS has been and
remains strongly linked with the mammography industry, while ignoring or attacking
the development of viable alternatives (39).
ACS promotion continues to lure women of all ages into mammography centers,
leading them to believe that mammography is their best hope against breast cancer.
A leading Massachusetts newspaper featured a photograph of two women in their
twenties in an ACS advertisement that promised early detection results in a cure
««nearly 100 percent of the time.»» An ACS communications director, questioned by
journalist Kate Dempsey, admitted in an article published by the Massachusetts
Women's Community's journal Cancer, ««The ad isn't based on a study. When you
make an advertisement, you just say what you can to get women in the door. You
exaggerate a point. . . . Mammography today is a lucrative [and] highly competitive
business»» (39).
NEEDED REFORMS
Mammography is a striking paradigm of the capture of unsuspecting women by
runaway powerful technological and pharmaceutical global industries, with the
complicity of the cancer establishment, particularly the ACS, and the rollover
mainstream media. Promotion of the multibillion dollar mammography screening
industry has also become a diversionary flag around which legislators and women's
product corporations can rally, protesting how much they care about women, while
studiously avoiding any reference to avoidable risk factors of breast cancer, let alone
other cancers.
Screening mammography should be phased out in favor of annual CBE and monthly
BSE, as an effective, safe, and low-cost alternative, with diagnostic mammography
available when so indicated. Such action is all the more critical and overdue in view
of the still poorly recognized evidence that screening mammography does not lead to
decreased breast cancer mortality (18, 21, 23).
Networks of CBE and BSE clinics, staffed by trained nurses, should be established
internationally, including in developing nations. These low-cost clinics would further
empower women by providing them with scientific evidence on breast cancer risk
factors and prevention, information of particular importance in view of the continued
high incidence of breast cancers, with an estimated 192,200 new U.S. cases predicted
for 2001 (47), exceeding the number for any previous years. The multibillion dollar
U.S. insurance and Medicare costs of mammography, besides those in other nations,
should be diverted to outreach and research on prevention of breast and other cancers
and on other women's health programs.
Acknowledgments -- The comments and advice of Dr. Cornelia Baines and Maryann
Napoli are gratefully acknowledged.
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Danger and Unreliability of Mammography
Breast Examination is a Safe, Effective, and Practical Alternative
by Samuel S. Epstein , Rosalie Bertell, Ph.D., GNSH and Barbara Seaman
Published in International Journal of Health Services, Volume 31, Number 3, Pages
605-615, 2001 Baywood Publishing Co., Inc.
Mammography screening is a profit-driven technology posing risks compounded by
unreliability. In striking contrast, annual clinical breast examination (CBE) by a trained
health professional, together with monthly breast self-examination (BSE), is safe, at
least as effective, and low in cost. International programs for training nurses how to
perform CBE and teach BSE are critical and overdue.
Contrary to popular belief and assurances by the U.S. media and the cancer
establishment--the National Cancer Institute (NCI) and American Cancer Society
(ACS)--mammography is not a technique for early diagnosis. In fact, a breast cancer
has usually been present for about eight years before it can finally be detected.
Furthermore, screening should be recognized as damage control, rather than
misleadingly as ««secondary prevention.
DANGERS OF SCREENING MAMMOGRAPHY
Mammography poses a wide range of risks of which women worldwide still remain
uninformed.
Radiation Risks
Radiation from routine mammography poses significant cumulative risks of initiating
and promoting breast cancer (1-3). Contrary to conventional assurances that radiation
exposure from mammography is trivial--and similar to that from a chest X-ray or
spending one week in Denver, about 1/1,000 of a rad (radiation-absorbed dose)--the
routine practice of taking four films for each breast results in some 1,000-fold greater
exposure, 1 rad, focused on each breast rather than the entire chest (2). Thus,
premenopausal women undergoing annual screening over a ten-year period are
exposed to a total of about 10 rads for each breast. As emphasized some three
decades ago, the premenopausal breast is highly sensitive to radiation, each rad of
exposure increasing breast cancer risk by 1 percent, resulting in a cumulative 10
percent increased risk over ten years of premenopausal screening, usually from ages
40 to 50 (4); risks are even greater for ««baseline»» screening at younger ages, for
which there is no evidence of any future relevance. Furthermore, breast cancer risks
from mammography are up to fourfold higher for the 1 to 2 percent of women who are
silent carriers of the A-T (ataxia-telangiectasia) gene and thus highly sensitive to the
carcinogenic effects of radiation (5); by some estimates this accounts for up to 20
percent of all breast cancers annually in the United States (6).
Cancer Risks from Breast Compression
As early as 1928, physicians were warned to handle ««cancerous breasts with care--
for fear of accidentally disseminating cells»» and spreading cancer (7). Nevertheless,
mammography entails tight and often painful compression of the breast, particularly
in premenopausal women. This may lead to distant and lethal spread of malignant
cells by rupturing small blood vessels in or around small, as yet undetected breast
cancers (8).
Delays in Diagnostic Mammography
As increasing numbers of premenopausal women are responding to the ACS's
aggressively promoted screening, imaging centers are becoming flooded and
overwhelmed. Resultingly, patients referred for diagnostic mammography are now
experiencing potentially dangerous delays, up to several months, before they can be
examined (9).
UNRELIABILITY OF MAMMOGRAPHY
Falsely Negative Mammograms
Missed cancers are particularly common in premenopausal women owing to the dense
and highly glandular structure of their breasts and increased proliferation late in their
menstrual cycle (10, 11). Missed cancers are also common in post-menopausal
women on estrogen replacement therapy, as about 20 percent develop breast
densities that make their mammograms as difficult to read as those of premenopausal
women (12).
Interval Cancers
About one-third of all cancers--and more still of premenopausal cancers, which are
aggressive, even to the extent of doubling in size in one month, and more likely to
metastasize--are diagnosed in the interval between successive annual mammograms
(2, 13). Premenopausal women, particularly, can thus be lulled into a false sense of
security by a supposedly negative result on an annual mammogram and fail to seek
medical advice.
Falsely Positive Mammogram
Mistakenly diagnosed cancers are particularly common in premenopausal women, and
also in postmenopausal women on estrogen replacement therapy, resulting in
needless anxiety, more mammograms, and unnecessary biopsies (14, 15). For women
with multiple high-risk factors, including a strong family history, prolonged use of the
contraceptive pill, early menarche, and nulliparity--just those groups that are most
strongly urged to have annual mammograms--the cumulative risk of false positives
increases to ««as high as 100 percent»» over a decade's screening (16).
Overdiagnosis
Overdiagnosis and subsequent overtreatment are among the major risks of
mammography. The widespread and virtually unchallenged acceptance of screening
has resulted in a dramatic increase in the diagnosis of ductal carcinoma-in-situ (DCIS),
a pre-invasive cancer, with a current estimated incidence of about 40,000 annually.
DCIS is usually recognized as micro-calcifications and generally treated by
lumpectomy plus radiation or even mastectomy and chemotherapy (17). However,
some 80 percent of all DCIS never become invasive even if left untreated (18).
Furthermore, the breast cancer mortality from DCIS is the same-- about 1 percent--
both for women diagnosed and treated early and for those diagnosed later following
the development of invasive cancer (17). That early detection of DCIS does not reduce
mortality is further confirmed by the 13-year follow-up results of the Canadian National
Breast Cancer Screening Study (19). Nevertheless, as recently stressed, ««the public
is much less informed about overdiagnosis than false positive results. In a recent
nationwide survey of women, 99 percent of respondents were aware of the possibility
of false positive results from mammography, but only 6 percent were aware of either
DCIS by name or the fact that mammography could detect a form of `cancer' that often
doesn't progress»» (20).
Quality Control
In 1992 Congress passed the National Mammography Standards Quality Assurance
Act requiring the Food and Drug Administration (FDA) to ensure that screening centers
review their results and performance: collect data on biopsy outcomes and match them
with the original radiologist's interpretation of the films (21). However, the centers do
not release these data because the Act does not require them to do so. It is essential
that this information now be made fully public so that concerns about the reliability of
mammography can be further evaluated. Activist breast cancer groups would most
likely strongly support, if not help to initiate, such overdue action by the FDA.
FAILURE TO REDUCE BREAST CANCER MORTALITY
Despite the long-standing claims, the evidence that routine mammography screening
allows early detection and treatment of breast cancer, thereby reducing mortality, is at
best highly questionable. In fact, ««the overwhelming majority of breast cancers are
unaffected by early detection, either because they are aggressive or slow growing»»
(21). There is supportive evidence that the major variable predicting survival is
««biological determinism--a combination of the virulence of the individual tumor plus
the host's immune response,»» rather than just early detection (22).
Claims for the benefit of screening mammography in reducing breast cancer mortality
are based on eight international controlled trials involving about 500,000 women (23).
However, recent meta-analysis of these trials revealed that only two, based on 66,000
postmenopausal women, were adequately randomized to allow statistically valid
conclusions (23). Based on these two trials, the authors concluded that ««there is no
reliable evidence that screening decreases breast cancer mortality--not even a
tendency towards an effect.»» Accordingly, the authors concluded that there is no
longer any justification for screening mammography; further evidence for this
conclusion will be detailed at the May 6, 2001, annual meeting of the National Breast
Cancer Coalition in Washington, D.C., and published in the July report of the Nordic
Cochrane Centre.
Even assuming that high quality screening of a population of women between the ages
of 50 and 69 would reduce breast cancer mortality by up to 25 percent, yielding a
reduced relative risk of 0.75, the chances of any individual woman benefiting are
remote (18). For women in this age group, about 4 percent are likely to develop breast
cancer annually, about one in four of whom, or 1 percent overall, will die from this
disease. Thus, the 0.75 relative risk applies to this 1 percent, so 99.75 percent of the
women screened are unlikely to benefit.
THE UNITED STATES VERSUS OTHER NATIONS
No nation other than the United States routinely screens premenopausal women by
mammography. In this context, it may be noted that the January 1997 National
Institutes of Health Consensus Conference recommended against premenopausal
screening (24), a decision that the NCI, but not the ACS, accepted (4). However, under
pressure from Congress and the ACS, the NCI reversed its decision some three
months later in favor of premenopausal screening. The U.S. overkill extends to the
standard practice of taking two or more mammograms per breast annually in
postmenopausal women. This contrasts with the more restrained European practice
of a single view every two to three years (4).
BREAST EXAMINATION IS A SAFE AND EFFECTIVE ALTERNATIVE TO
MAMMOGRAPHY
That most breast cancers are first recognized by women themselves was admitted in
1985 by the ACS, an aggressive advocate of routine mammography for all women
over the age of 40: ««We must keep in mind the fact that at least 90 percent of the
women who develop breast carcinoma discover the tumors themselves»» (25).
Furthermore, as previously shown, ««training increases reported breast self-
examination frequency, confidence, and the number of small tumors found»» (26).
A pooled analysis of several 1993 studies showed that women who regularly
performed BSE detected their cancers much earlier and with fewer positives nodes
and smaller tumors than women failing to examine themselves (27); BSE would also
enhance earlier detection of missed or interval cancers, especially in pre-menopausal
women (28). There is a strong consensus that the effectiveness of BSE critically
depends on careful training by skilled professionals, and that confidence in BSE is
enhanced with annual CBEs by an experienced professional using structured
individual training (29). The tactile sensitivity of BSE can be increased by the use of
Mammacare techniques to enhance lump detection skills (30, 31), and by the use of
FDA-approved and nonprescription thin and pliable lubricant-filled sensor pads (32,
33).
In a joint U.S. and Chinese large-scale trial based on 520 Chinese factories, women
in half the factories were trained in and practiced BSE, while the other group of women
served as controls (34). The five-year follow up results reported no reduction in breast
cancer mortality in women in the BSE group. However, these findings are of little, if
any, significance in view of the minimum of a 10- to 13-year period required before the
efficacy of mammography is claimed to occur in premenopausal women (24),
especially as some of the trial's participants were in their thirties (28).
The critical importance and reliability of CBE has been strikingly confirmed by the
recent Canadian National Breast Cancer Screening Study (19). This reported the
results of a unique individually randomized controlled trial on some 40,000 women,
aged 50 to 59 on entry, followed by record linkage for nine to 13 years, with active
follow-up of cancer patients for an additional three years. Half the women performed
monthly BSE, following instruction by trained nurses, had annual CBEs (taking
approximately ten minutes) by trained nurses, and had annual mammograms, while
the other half practiced BSE and had annual CBEs but no mammograms. It should be
noted that the CBE performance by trained nurses had been shown to be as good as,
if not better than, that of the study surgeons (35), a finding of particular interest in view
of the growing perception among women that professional women are more sensitive
than men to women's health issues (36). The results of this study provide clear
evidence on the reliability of CBE, in association with BSE (19): ««In women age 50-59
years, the addition of annual mammography screening to physical examination has no
impact on breast cancer mortality.»» In other words, the mammographic detection of
nonpalpable cancers failed to improve survival rates, as ««the majority of the small
cancers detected by mammography represent pseudo-disease or overdiagnosis»»
(37); confirmation of this explanation awaits a trial, a protocol of which is available,
comparing mammography alone with physical examination alone. It should further be
noted that the mammogram group had a three-fold increase in the number of false
positives compared with the CBE and BSE group, resulting in unnecessary biopsies.
The effectiveness of CBE is further supported by the results of a new Japanese mass
screening study (38). Breast cancer mortality was compared in municipalities with or
without ««high coverage»» by CBE. The age-adjusted breast cancer mortality between
1986-1990 and 1991-1995 was reduced by over 40 percent in ««high coverage»»
municipalities, in contrast to only 3 percent in controls.
In spite of such evidence, the ACS and radiologists persist in their dismissiveness of
CBE and BSE, particularly as ««a substitute for screening practices that have a
`proven' benefit such as mammograms»» (33). The NCI no longer prints a BSE guide
in its breast cancer booklet, claiming that ««no studies have clearly shown a benefit
of using BSE»»; similarly, the ACS no longer distributes information on BSE, such as
shower-hanger cards.
There are immediate needs for a large-scale crash program for training nurses in how
to perform annual CBE and how to teach BSE. This need is critical for underinsured
and uninsured low-socioeconomic and ethnic women in the United States, and even
more so for developing countries. Once well trained, women of all social and cultural
classes could perform monthly BSE, at no cost or risk apart from false positives, which
decrease with increasing practice, along with annual CBE screening. Clinics offering
CBE and training in BSE could be established nationwide, and eventually worldwide,
in a network of clinics, community hospitals, churches, synagogues, and mosques.
These clinics could also act as a comprehensive source of reliable information on how
to reduce the risks of breast cancer, about which women still remain largely
uninformed by the cancer establishment (2). Besides lifestyle and reproductive risk
factors, emphasis should be directed to the massive overprescription of carcinogenic
hormonal drugs and the avoidable and involuntary exposures to petrochemical and
radionuclear carcinogens in the totality of the environment (39-41).
COSTS OF SCREENING
The dangers and unreliability of mammography screening are compounded by its
growing and inflationary costs; Medicare and insurance average costs are $70 and
$125, respectively. Inadequate Medicare reimbursement rates are now prompting
fewer hospitals and clinics to offer mammograms, and deterring young doctors from
becoming radiologists. Accordingly, Senators Charles Schumer (D-NY) and Tom
Harkin (D-IA) are introducing legislation to raise Medicare reimbursement to $100 (42).
If all U.S. premenopausal women, about 20 million according to the Census Bureau,
submitted to annual mammograms, minimal annual costs would be $2.5 billion (4).
These costs would be increased to $10 billion, about 5 percent of the $200 billion 2001
Medicare budget, if all postmenopausal women were also screened annually, or about
14 percent of the estimated Medicare spending on prescription drugs. Such costs will
further increase some fourfold if the industry, enthusiastically supported by
radiologists, succeeds in its efforts to replace film machines, costing about $100,000,
with the latest high-tech digital machines, approved by the FDA in November 2000,
costing about $400,000. Screening mammography thus poses major threats to the
financially strained Medicare system. Inflationary costs apart, there is no evidence of
the greater effectiveness of digital than film mammography (43), as confirmed by a
study reported at the November 2000 annual meeting of the Radiological Society of
North America (44). In fact, digital mammography is likely to result in the increased
diagnosis of DCIS.
The comparative cost of CBE and mammography in the 1992 Canadian Breast Cancer
Screening Study was reported to be 1 to 3 (45). However, this ratio ignores thehigh
costs of capital items including buildings, equipment, and mobile vans, let alone the
much greater hidden costs of unnecessary biopsies, specialized staff training, and
programs for quality control and professional accreditation (46). This ratio could be
even more favorable for CBE and BSE instruction if both were conducted by trained
nurses. The excessive costs of mammography screening should be diverted away
from industry to breast cancer prevention and other women's health programs.
CONFLICTS OF INTEREST
The ACS has close connections to the mammography industry (39). Five radiologists
have served as ACS presidents, and in its every move, the ACS promotes the interests
of the major manufacturers of mammogram machines and films, including Siemens,
DuPont, General Electric, Eastman Kodak, and Piker. The mammography industry
also conducts research for the ACS and its grantees, serves on advisory boards, and
donates considerable funds. DuPont also: is a substantial backer of the ACS Breast
Health Awareness Program; sponsors television shows and other media productions
touting mammography; produces advertising, promotional, and information literature
for hospitals, clinics, medical organizations, and doctors; produces educational films;
and, of course, lobbies Congress for legislation promoting availability of
mammography services. In virtually all its important actions, the ACS has been and
remains strongly linked with the mammography industry, while ignoring or attacking
the development of viable alternatives (39).
ACS promotion continues to lure women of all ages into mammography centers,
leading them to believe that mammography is their best hope against breast cancer.
A leading Massachusetts newspaper featured a photograph of two women in their
twenties in an ACS advertisement that promised early detection results in a cure
««nearly 100 percent of the time.»» An ACS communications director, questioned by
journalist Kate Dempsey, admitted in an article published by the Massachusetts
Women's Community's journal Cancer, ««The ad isn't based on a study. When you
make an advertisement, you just say what you can to get women in the door. You
exaggerate a point. . . . Mammography today is a lucrative [and] highly competitive
business»» (39).
NEEDED REFORMS
Mammography is a striking paradigm of the capture of unsuspecting women by
runaway powerful technological and pharmaceutical global industries, with the
complicity of the cancer establishment, particularly the ACS, and the rollover
mainstream media. Promotion of the multibillion dollar mammography screening
industry has also become a diversionary flag around which legislators and women's
product corporations can rally, protesting how much they care about women, while
studiously avoiding any reference to avoidable risk factors of breast cancer, let alone
other cancers.
Screening mammography should be phased out in favor of annual CBE and monthly
BSE, as an effective, safe, and low-cost alternative, with diagnostic mammography
available when so indicated. Such action is all the more critical and overdue in view
of the still poorly recognized evidence that screening mammography does not lead to
decreased breast cancer mortality (18, 21, 23).
Networks of CBE and BSE clinics, staffed by trained nurses, should be established
internationally, including in developing nations. These low-cost clinics would further
empower women by providing them with scientific evidence on breast cancer risk
factors and prevention, information of particular importance in view of the continued
high incidence of breast cancers, with an estimated 192,200 new U.S. cases predicted
for 2001 (47), exceeding the number for any previous years. The multibillion dollar
U.S. insurance and Medicare costs of mammography, besides those in other nations,
should be diverted to outreach and research on prevention of breast and other cancers
and on other women's health programs.
Acknowledgments -- The comments and advice of Dr. Cornelia Baines and Maryann
Napoli are gratefully acknowledged.
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