Go to NIH Consensus Program Home Page This statement will be published as: Breast
Cancer Screening for Women Ages 40-49. NIH Consens Statement 1997
January 21-23;15(1): in press. For making bibliographic reference
to consensus statement no. 103 in the electronic form displayed
here, it is recommended that the following format be used: NIH
Consens Statement Online 1997 January 21-23 [cited year, month,
day]; 15(1): in press.
NIH Consensus Statements are prepared by a nonadvocate,
non-Federal panel of experts, based on (1) presentations by
investigators working in areas relevant to the consensus
questions during a 2-day public session; (2) questions and
statements from conference attendees during open discussion
periods that are part of the public session; and (3) closed
deliberations by the panel during the remainder of the second day
and morning of the third. This statement is an independent report
of the consensus panel and is not a policy statement of the NIH
or the Federal Government.
Contents
FOREWORD
The NIH Consensus Development Program, managed by the Office of
Medical Applications of Research, is a unique technology
assessment process in American medicine and is designed to
produce a consensus statement at the end of a 3-day consensus
conference. A consensus statement is a thoughtful and thorough
data-driven synthesis of the current science based on a
comprehensive review of the existing peer-reviewed medical
literature, a series of state-of-the-art scientific
presentations, and public testimony. The resulting statement
helps to advance and clarify the field of science it addresses
and provides an important and useful public health message.
The existence of controversy is a major criterion for determining
the need to conduct an NIH consensus development conference. As
such, there may be times when a panel cannot reach a consensus,
or that the panel's consensus is that there is no consensus. All
NIH consensus panels are offered the opportunity to make a
minority statement if a consensus cannot be obtained. In the
previous 102 consensus conferences held by NIH over the past 20
years, this has happened on only two occasions.
This NIH Consensus Statement on Breast Cancer Screening for Women
Ages 40-49 contains a minority report. While a consensus was
initially achieved by the entire panel at the end of the
consensus conference, two of the twelve panel members
subsequently differed on specific issues in the draft document in
the weeks that followed and, ultimately, did not agree entirely
with the majority statement.
The panel members writing the majority report took into
consideration the risks versus the benefits of mammography and
did not think that the data supported a recommendation for
universal mammography screening for all women in their forties.
The authors of the minority report believed the risks to be
overemphasized by the majority and concluded the data did support
a recommendation for mammography screening for all women in this
age group. The entire panel did agree that women and their health
care providers should be provided information on these issues
upon which to base their decisions. Additionally, all panelists
agreed that for women in their forties who choose to have
mammography, the costs of mammograms should be reimbursed by
third-party payors or covered by health maintenance
organizations.
It is in the spirit of providing all views on this controversial
topic that both the majority and minority statements are
presented.
John H. Ferguson, M.D.
Director
Office of Medical Applications of Research
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ABSTRACT
Objective. To provide health care providers, patients, and
the general public with a responsible assessment of currently
available data regarding the effectiveness of mammography
screening for women ages 40-49.
Participants. A non-Federal, nonadvocate, 12-member panel
representing the fields of oncology, radiology, obstetrics and
gynecology, geriatrics, public health, and epidemiology and
including patient representatives. In addition, 32 experts in
oncology, surgical oncology, radiology, public health, and
epidemiology, presented data to the panel and to a conference
audience of 1,100.
Evidence. The literature was searched through Medline and
an extensive bibliography of references was provided to the panel
and the conference audience. Experts prepared abstracts with
relevant citations from the literature. Scientific evidence was
given precedence over clinical anecdotal experience.
Consensus Process. The panel, answering predefined
questions, developed its conclusions based on the scientific
evidence presented in open forum and the scientific literature.
The panel composed a draft statement that was read in its
entirety and circulated to the experts and the audience for
comment. Thereafter, the panel resolved conflicting
recommendations and released a revised draft statement at the end
of the conference. The final statement with a minority report was
completed within several weeks after the conference.
Conclusions. The Panel concludes that the data currently
available do not warrant a universal recommendation for
mammography for all women in their forties. Each woman should
decide for herself whether to undergo mammography. Her decision
may be based not only on an objective analysis of the scientific
evidence and consideration of her individual medical history, but
also on how she perceives and weighs each potential risk and
benefit, the values she places on each, and how she deals with
uncertainty. However, it is not sufficient just to advise a woman
to make her own decision about mammograms. Given both the
importance and the complexity of the issues involved in assessing
the evidence, a woman should have access to the best possible
relevant information regarding both benefits and risks, presented
in an understandable and usable form. Information should be
developed for women in their forties regarding potential benefits
and risks to be provided to enable each woman to make the most
appropriate decision. In addition, educational material to
accompany this information should be prepared that will lead
women step by step through the process of using such information
in the best possible way for reaching a decision. For women in
their forties who choose to have mammography performed, the costs
of the mammograms should be reimbursed by third-party payors or
covered by health maintenance organizations so that financial
impediments will not influence a woman's decision. Additionally,
a woman's health care provider must be equipped with sufficient
information to facilitate her decisionmaking process. Therefore,
educational material for physicians should be developed to assist
them in providing the guidance and support needed by the women in
their care who are making difficult decisions regarding
mammography. The two panel members writing a minority report
believed the risks of mammography to be overemphasized by the
majority and concluded that the data did support a recommendation
for mammography screening for all women in this age group and
that the survival benefit and diagnosis at an earlier stage
outweigh the potential risks.
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INTRODUCTION
Breast cancer is the single leading cause of death for women ages
40-49 in the United States. A 40-year-old woman has a 2 percent
chance of being diagnosed with invasive breast cancer or ductal
carcinoma in situ in the next 10 years, and her chance of
dying from breast cancer during this decade is 0.3 percent. In
addition to morbidity and mortality from breast cancer itself, a
toll is taken by the emotional impact of both the disease and its
treatment and by the fear engendered from the threat of
developing the disease.
To what extent can early detection through mammographic screening
reduce the impact of breast cancer in women in their forties, and
what risks may be associated with mammography in this age group?
Although nonrandomized observational data on women screened with
mammography have been reported, the benefits and risks of
mammography screening for women in their forties can be validly
assessed only by analyzing results obtained from clinical trials
in which women are randomly assigned to be screened or not
screened. A number of randomized clinical trials in 50- to
69-year-old women have shown clearly that early detection of
breast cancer by mammography at regular intervals, with and
without clinical breast examination (CBE), reduces breast cancer
mortality by about one-third. However, the results have not been
as clear for women ages 40-49. Internationally, experts have
continued to examine data regarding the use of mammography in
this age group. Results of several trials in different countries
have been updated recently with longer periods of observation.
To address this issue and to examine newly available data from
both observational studies and randomized trials, the National
Cancer Institute, together with the Office of Medical
Applications of Research of the National Institutes of Health,
convened a Consensus Development Conference on Breast Cancer
Screening for Women Ages 40-49. The conference was cosponsored by
the National Institute on Aging, the Office of Research on
Women's Health of the NIH and the Centers for Disease Control and
Prevention. Following a day and a half of presentations by
experts in the relevant fields and discussion from the audience,
an independent consensus panel composed of specialists and
generalists, (including epidemiologists, statisticians,
radiologists, oncologists), representatives from the public, and
other experts, considered the evidence and formulated a consensus
statement in response to the following five predefined questions:
1. IS THERE A REDUCTION IN MORTALITY
FROM BREAST CANCER DUE TO SCREENING WOMEN AGES 40-49 WITH
MAMMOGRAPHY, WITH OR WITHOUT PHYSICAL EXAMINATION? HOW LARGE IS
THE BENEFIT? HOW DOES THIS CHANGE WITH AGE?
Information regarding the usefulness of screening procedures is
provided by randomized controlled trials (RCTs) in which
participants are randomly assigned to receive or not receive
screening. Currently available data from eight RCTs in different
countries that included women ages 40-49 have been used to
examine the effect of screening mammography on breast cancer
mortality. Such studies must include long term followup in order
to account for the variable course of breast cancer and to
examine the ultimate benefit-a reduction in mortality from breast
cancer. In fact, the benefit of reduced breast cancer mortality
in the summary of these studies is about half that seen in women
ages 50-69. About twice as much followup time is needed to see
the benefits.
These trials were begun between 1963 and 1982. On the basis of a
summary of data from these RCTs, there is no statistically
significant difference in breast cancer mortality within 7 years
after screening is initiated, between women randomized to receive
or not receive screening. Summary data in five of eight RCTs show
a trend towards reduced breast cancer mortality only after a
follow up of 10 or more years, with the decrease estimated at 16
percent (with confidence intervals from 2 percent to 28 percent).
In the RCTs, many of the women began mammography while they were
in their late forties, and continued to have mammography after
age 50. Consequently, one cannot determine if the women who
benefited from mammography in these studies showed this benefit
because of breast cancer diagnosis following mammographic
screening performed after age 50.
Based on meta-analyses of the RCTs, regular screening of 10,000
women ages 40-49 would result in extension of the lives of 0---10
women. About 2,500 women would have to be screened regularly in
order to extend 1 life. For those women whose survival is
extended, the length of life extension is not known.
The magnitude of the benefit seen in the RCTs may be
underestimates for several reasons. None of these trials except
one was specifically designed to study women in their forties. In
all the trials, some women assigned to screening were not
screened, and some assigned to the control group obtained
screening outside the trial. Trials varied in the length of the
screening interval used, ranging from 1 to 2 years, which may be
too long to detect fast-growing cancers before they become
clinically evident. Finally, current mammographic technology has
improved in the past 15 years from that used in the RCTs
initiated between 1963 and 1982. Many of the same factors operate
in RCTs of women ages 50-69 years, so that the benefits could
also have been underestimated in older women.
The incidence of breast cancer approximately doubles from ages
40-44 to 45-49. This increased incidence suggests that any
benefit of mammography in women ages 40-49 may be greater for
women in their late forties. Because a disproportionate number of
women in the screening phase of these trials were in their late
forties, it is difficult to assess the relative benefits of
mammography for the younger women within the 40- to 49-year-old
group compared with the older women.
In addition to RCTs, uncontrolled case series comparing women
with mammographically detected breast cancer to women with
clinically detected cancers show that mammography finds breast
cancers at an earlier stage. Earlier stage cancers generally have
better prognoses. However, it is not necessarily valid to
conclude that screening mammography results in fewer breast
cancer deaths, because screening selectively identifies women
with slow-growing cancers whose prognosis is better, regardless
of treatment. Detection at an earlier stage is relevant only if
it can be shown in a randomized study that fewer deaths occur in
a screened population than in a comparable unscreened control
population.
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2. WHAT ARE THE RISKS ASSOCIATED WITH
SCREENING WOMEN AGES 40-49 WITH MAMMOGRAPHY, AND WITH PHYSICAL
EXAMINATION? HOW LARGE ARE THE RISKS? HOW DO THEY CHANGE WITH
AGE?
Understanding the nature and magnitude of risks is important to
both primary care providers and women making informed decisions
about breast cancer screening. Critical issues include the
following: risks associated with false-negative examinations,
additional diagnostic testing induced by false-positive
examinations, psychosocial consequences of abnormal examinations,
potential risk of overtreatment of low-risk or in situ
cancers, and potential risk from radiation exposure.
False-Negative Mammograms
Up to one-fourth of all invasive breast cancers are not detected
by mammography in 40- to 49-year-olds, compared with one-tenth of
cancers in 50- to 69-year-olds. Women with these cancers may be
harmed if their diagnosis or treatment is delayed because of a
normal, or false-negative, mammogram. Professional and public
education as well as disclaimers on mammography reports have
increased the awareness of this problem in women with clinical
symptoms, but more attention should be given to the issue in
screened women.
False-Positive Mammograms
Many mammographic abnormalities may not be cancer, but will
prompt additional testing and anxiety. Approximately 10 percent
of all screening mammograms are read as abnormal, each of which
will prompt the performance of an average of two additional
diagnostic tests such as diagnostic mammography, ultrasound,
needle aspiration, core biopsy, or surgical biopsy. Given the
lower incidence of breast cancer in 40- to 49-year-old women
compared with that in older women, false-positive examinations
are more common in younger women and the proportion of
true-positive examinations increases with increasing age. As many
as 3 out of 10 women who begin annual screening at age 40 will
have an abnormal mammogram during the next decade. For women ages
40-49 undergoing breast biopsy for mammographic findings, only
half as many cancers are diagnosed compared with women ages
50-69. For every eight biopsies performed in the younger age
group, one invasive and one in situ breast cancer are
found.
Psychosocial Consequences
There is concern that women having abnormal mammograms-both
true-positive and false- positive-experience psychosocial
sequelae, including anxiety, fear, and inconvenience. Additional
information is needed on whether experiencing a false-positive
mammogram may affect subsequent willingness to undergo future
screening mammography at ages when it is of greatest benefit.
Low-Risk Cancer and Ductal Carcinoma In Situ
Not all women diagnosed with breast cancer by mammographic
screening are helped by early detection. Some have slowly growing
cancers that may be successfully treated when discovered later.
Some cancers that might be detected in women in their forties are
so slow growing that they could be detected by mammograms after
age 50 and treated at that time. Earlier detection may cause
additional months or years of cancer-related anxiety, affecting
personal and workplace relationships, as well as insurance
coverage.
Ductal carcinoma in situ (DCIS) is frequently diagnosed in
mammographically screened women ages 40-49. DCIS is a
heterogeneous entity for which the natural history, clinical
significance, prognostic factors, and treatment are uncertain.
Because some cases of DCIS may not progress to invasive cancer, a
risk of overtreatment exists.
Radiation Exposure
The risk of radiation-induced breast cancer has long been a
concern to mammographers and has driven the efforts to reduce the
radiation dose per examination. Radiation has been shown to cause
breast cancer in women, and the risk is proportional to dose. The
younger the woman at the time of exposure, the greater her
lifetime risk for breast cancer. Radiation-related breast cancers
occur at least 10 years after exposure. However, breast cancer as
a result of the radiation dose associated with mammography has
not been demonstrated. Radiation from yearly mammograms during
ages 40-49 has been estimated as possibly causing 1 additional
breast cancer death per 10,000 women. However, this estimate is
based on statistical models from epidemiological studies of
high-dose exposures, and the actual risk at the lower doses
associated with mammography could range from much higher than
one, to nonexistent. Women with inherited or acquired defects in
DNA repair mechanisms may have a different susceptibility to the
effects of radiation.
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3. ARE THERE OTHER BENEFITS? IF SO,
WHAT ARE THEY? HOW DO THEY CHANGE WITH AGE?
Additional benefits from screening women ages 40-49 may include
earlier detection and increased compliance. Data from several
studies suggest that the average size of newly diagnosed breast
cancer is decreasing and the proportion of stages 0 and I cancers
(i.e., DCIS and small invasive breast cancer) is increasing due
to mammographic screening in women ages 40-49. The increased
detection of DCIS may prove beneficial if it leads to a
subsequent decrease in the incidence of invasive cancer. This
increased detection and treatment of early-stage cancer or
premalignant changes could be consistent with a reduction in
breast cancer mortality appearing only after 10 years following
the initiation of screening.
The diagnosis of breast cancer at a smaller size or earlier stage
will allow a woman more choice in selecting among various
treatment options. For example, more women with cancer detected
by mammography have the option of lumpectomy, rather than
mastectomy, compared with women whose cancers are detected by
palpation. Studies also show that the rate of axillary dissection
or chemotherapy may be reduced among women who have smaller or
earlier stage cancer. This choice in type of treatment allows a
woman a measure of control over treatment decisions. The value of
this benefit must be individually assessed.
Bringing women into screening programs at a younger age could
provide an earlier opportunity for patient education and increase
their access to, and utilization of, health care. However, there
is no information on whether initiating mammographic screening at
age 40 would increase or decrease screening compliance in later
years.
Women with true negative mammogram screening tests may benefit
from reassurance that they do not have breast cancer. However,
the reassurance value of a true-negative screen has not been
studied and is complicated by the fact that it is not possible to
distinguish true negatives from false negatives without
additional testing.
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4. WHAT IS KNOWN ABOUT HOW THE BENEFITS
AND RISKS OF BREAST CANCER SCREENING DIFFER BASED ON KNOWN RISK
FACTORS FOR BREAST CANCER?
Although much is known about risk factors for breast cancer
incidence and mortality, little is known about the effects of
screening in high-risk subgroups. Known risk factors include
family history of breast cancer, having no children, and having a
first birth after age 30. None of the RCTs of breast cancer
screening for women in their forties has examined the effect of
screening on the mortality of women in any of the high-risk
subgroups. Most of these trials included only white women.
Although the incidence of breast cancer is the same for
African-American women and white women in their forties,
African-American women have a 50 percent higher breast cancer
mortality rate than white women in this age group. An outreach
screening program enrolling a large number of women from minority
groups has reported some ethnic or racial differences in cancer
detection rates from false-positive mammograms. In particular,
Hispanic and Native-American women have higher false-positive
rates than white women in their forties. A practice-based
screening program including women ages 40-49 found a higher
cancer detection rate and a lower false-positive rate for women
with a family history of breast cancer.
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5. WHAT ARE THE DIRECTIONS FOR FUTURE
RESEARCH?
There are insufficient data to address several aspects of
screening mammography. Although the focus of this conference has
been specifically on women ages 40-49, future research should
examine the effects of mammography for all ages at risk. Age is a
continuum; although one can use an artificial cutoff of 50 as an
approximation of the age of menopause and its associated biologic
changes, age should be studied as a continuum. The ongoing UK-AGE
and Eurotrials may add valuable information on benefits and risks
of screening specifically in this age group.
Most of the following research questions should be answered for
women of all ages:
CONCLUSIONS
Mammography has been shown to be effective in reducing breast
cancer mortality in women ages 50-69. Currently available
evidence from RCTs indicates that for women ages 40-49, during
the first 7-10 years following initiation of screening, breast
cancer mortality is no lower in women who were assigned to
screening than in controls. Summary data indicate a reduction of
16 percent in breast cancer mortality after about 10 years, with
confidence intervals of 2-28 percent. However, although some
studies find lower mortality from breast cancer in screened women
after 10 years, others do not. A lower mortality could be a
result of the original screening but could also be due to other
factors such as CBE or mammography offered to the women after age
50.
Further complicating this issue is that the charge to the panel
focused on a broad age range, 40-49 years. The rationale for the
charge was that evidence for recommending mammography is strong
for women ages 50 and above, but not as clear for 40- to
49-year-old women. It should be pointed out that of all the
studies reviewed, only one was specifically designed originally
to evaluate mammography in the 40- to 49-year-old age group.
However, age is a continuum and biologically there is no abrupt
change at age 50. Indeed, a 49-year-old woman is probably more
similar to a 50-year-old woman than she is to a 40-year-old.
Unfortunately, the data needed upon which to base recommendations
for narrower age ranges are not available. The panel concludes
that presently available evidence does not warrant a universal
recommendation for mammography screening of women ages 40-49.
This conclusion does not preclude the possibility that older
women in this age group might have a different balance of benefit
and risk than do younger women. Data to support this possibility
are not presently available. The effects of different ages at
menopause also remain to be explored.
The potential benefits of mammography for women in their forties
include earlier diagnosis and the option to choose
breast-conserving therapy. These benefits must be weighed against
the risks or potential risks, including those associated with
false-positive tests: further diagnostic tests which may be
invasive, anxiety and inconvenience, as well as potential risk
from mammographic radiation. In addition, the impact of false
reassurance given to women with false-negative screens must be
considered, given the lower sensitivity of mammography in women
in their forties compared with women in their fifties.
Professional and public education as well as disclaimers on
mammography reports have increased awareness of false negatives
in women with clinical symptoms such as a palpable lump.
Similarly, those recommending mammographic screening of
asymptomatic women in this age group must also remind women and
their physicians to perform regular CBEs and to evaluate new
symptoms promptly.
Every decision to utilize or not utilize a health-related service
involves weighing available scientific evidence regarding
benefits and risks against personal values and prior experiences.
Such decisionmaking occurs at multiple levels and the
decisionmaking process will differ at each level. One level is
characterized by the question "Would you have this done for
yourself or for someone in your immediate family?" When the
available scientific evidence is equivocal and incomplete, a
person's decision to act or not act will be significantly
influenced by personal or family experience with the disease and
by one's capacity to deal with risk and uncertainty. Another
level of decisionmaking is when a physician makes recommendations
to his or her patients. Such a decision is generally based more
on the strength of the scientific evidence, but the physician's
recommendations may also be colored by prior experience, both
personally and with other patients, as well as by his or her
assessment of the patient for whom the recommendation will be
made. Finally, there is the level of deciding to make
across-the-board recommendations to a population, a decision that
has far-reaching implications and that must be based to a much
greater extent on a rigorous examination of the available
scientific evidence. Of all decision levels, this level requires
the strongest evidence of high benefit and low risk, particularly
in the case of screening mammography, where such recommendations
would be made to a healthy population. Thus, in some cases, a
physician might recommend mammography for a patient in her
forties and might do so despite a belief that the evidence is not
sufficiently strong to warrant across-the-board recommendations.
The panel concludes that the data currently available do not
warrant a universal recommendation for mammography for all women
in their forties. Each woman should decide for herself whether to
undergo mammography. Her decision may be based not only on an
objective analysis of the scientific evidence and consideration
of her individual medical history, but also on how she perceives
and weighs each potential risk and benefit, the values she places
on each, and how she deals with uncertainty. However, it is not
sufficient just to advise a woman to make her own decision about
mammograms. Given both the importance and the complexity of the
issues involved in assessing the evidence, a woman should have
access to the best possible relevant information regarding both
benefits and risks, presented in an understandable and usable
form. Information should be developed for women in their forties
regarding potential benefits and risks to be provided to enable
each woman to make the most appropriate decision. In addition,
educational material to accompany this information should be
prepared that will lead women step by step through the process of
using such information in the best possible way for reaching a
decision. For women in their forties who choose to have
mammography performed, the costs of the mammograms should be
reimbursed by third-party payors or covered by health maintenance
organizations so that financial impediments will not influence a
woman's decision.
Many women will seek guidance from their physicians who may be
primary care physicians or physicians in different specialties. A
woman's health care provider must be equipped with sufficient
information to facilitate her decision-making process. Therefore,
educational material for physicians should be developed to assist
them in providing the guidance and support needed by the women in
their care who are making difficult decisions regarding
mammography.
A system should be established for ongoing monitoring and review
of newly available information from research studies regarding
benefits and risks of mammography for women in their forties.
This will ensure timely formulation and implementation of any new
policy recommendations that may become appropriate in the future.
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MINORITY REPORT
We, the undersigned members of the panel, have different
interpretations of and derive different conclusions from the
available data. We state those differences below.
1. Is there a reduction in mortality from breast cancer due to
screening women ages 40-49 with mammography, with or without
physical examination? How large is the benefit? How does this
change with age?
Results from the eight randomized controlled trials indicate a
statistically significant 17 percent mortality reduction (p=0.05)
for women ages 40-49 at time of entry into the trials. Although
this survival benefit is less, on a population basis, than the
benefit for women in older decades, it is nevertheless
substantial. Furthermore, the potential biases in the RCTs would
act to underestimate this benefit.
2. What are the risks associated with screening women ages
40-49 with mammography, with or without physical examination? How
large are the risks? How do they change with age?
Although there is a theoretical risk from radiation exposure, if
it exists at all, it is very low. There is no measurable harm
from the diagnostic radiation doses used for screening
mammography.
The majority statement discusses potential harm from
false-negative mammograms, and the potential for adverse
psychosocial consequences from abnormal mammograms, but there are
no data to support or quantify these possibilities.
The majority statement suggests that detection of DCIS is a
potential harm. However, it is important to remember that all
breast epithelium is within the ductal system. Therefore,
biologically all invasive ductal and lobular cancers must begin
as in situ lesions. We do not know which DCIS will become
invasive cancer and which will not. All DCIS is classified as
cancer and must be taken seriously. Hence, detecting in situ cancer
is a goal of and therefore a benefit of screening mammography
rather than a harm.
An important risk for consideration is false-positive mammograms.
These occur at all ages, lead to additional studies, and may
cause anxiety and inconvenience. They constitute a measurable
risk about which all women should be informed. Reported
false-positive rates in mammography vary widely. Many of the
studies reporting such data do not include sufficient detail to
determine whether these rates vary significantly with decade of
age. However, from the available data, it is reasonable to
conclude that the false-positive rates for women in the 40-49 age
range are higher than for older women, but only slightly higher
than for women ages 50-59. False positive mammograms that lead to
additional views or breast ultrasound are generally considered to
be of little consequence. The more important group of false
positives are those that lead to biopsies for benign disease. The
estimate of 25 percent (two cancers per eight biopsies) given in
the majority statement is reasonable to expect for women in the
40-49 age group.
3. Are there other benefits? If so, what are they? How do they
change with age?
The majority statement states "Additional benefits may
include earlier detection" (italics added). There are
unequivocal data indicating that screening mammography in women
ages 40-49 does result in earlier detection. This earlier
detection is an important benefit apart from any survival
benefit. Detection at an earlier stage allows women more choice
in treatment options.
The majority statement states, "increased detection of DCIS may
prove beneficial if it leads to a subsequent decrease in the
incidence of invasive cancer" (italics added). We believe
the data do indicate that increased detection of DCIS leads to a
subsequent decrease in the incidence of invasive cancer, and this
is a highly desirable goal.
There are not sufficient reported data to quantitate the
difference in these benefits by age within the 40-49 age group.
However, the incidence of DCIS is similar across age groups.
Conclusions
We believe that the majority statement understates the benefits
of mammography for women ages 40-49, and overstates the potential
risks. We believe the data show a statistically significant
mortality reduction for women in their forties. We further
believe the survival benefit and diagnosis at an earlier stage
outweigh the potential risks.
There are no data to suggest that women are significantly harmed
by having extra mammographic views or breast ultrasound.
Furthermore, the false positive biopsy rate for mammography is
not different from the false positive biopsy rate for clinical
breast examination. Moreover, the false positive biopsy rate for
women ages 40-49 is only slightly higher than for women ages
50-59, an age range for which mammographic screening is widely
recommended.
Given our current understanding of breast cancer, it is
potentially dangerous to suggest that DCIS may not be clinically
important in women ages 40-49 and could safely be left undetected
until women are in their fifties. Questioning the benefits of
mammography for women ages 40-49 may cause significant harm from
delayed diagnosis.
A majority of the panel did not accept that a statistically
significant mortality reduction exists for women in their
forties, and so were unable to make a universal recommendation
for screening in this age group. We believe there is a
statistically significant mortality reduction. Based on this, we
make the same recommendation for screening all healthy women in
their forties. If we believe a certain recommendation is right
for a 45-year-old family member, we would (and do) make the same
recommendation to 45-year-old patients who come for advice, and
for 45-year-old women in general. We would alter that
recommendation only if there were characteristics of the
individual that were relevant. We agree that women should know
what data and value judgments we use to form our recommendations,
and we support their right to disagree with or reject our advice.
In summary, after evaluating and considering the evidence, we
believe that we should actively encourage routine screening
mammography for women in their forties. We also believe that
providing accurate information to women and their health care
providers is essential to assist women in deciding whether to
accept or reject that advice.
Daniel C. Sullivan M.D.
Ruthann T. Zern M.D.
Back to Contents
Consensus Development Panel
Leon Gordis, M.D.
Conference and Panel Chairperson
Professor
Department of Epidemiology
School of Hygiene and Public Health
Associate Dean for Admissions and Academic Affairs
School of Medicine
Johns Hopkins University
Baltimore, Maryland
Donald A. Berry, Ph.D.
Professor
Institute of Statistics and Decision Sciences and Cancer Center
Biostatistics
Duke University
Durham, North Carolina
Susan Y. Chu, Ph.D., M.P.H.
Associate Director
Center for Health Studies
Group Health Cooperative of Puget Sound
Seattle, Washington
Laurie L. Fajardo, M.D.
Professor of Radiology and Vice Chair for Research Department of
Radiology
University of Virginia
Charlottesville, Virginia
David G. Hoel, Ph.D.
Professor and Chairman
Department of Biometry and Epidemiology
Medical University of South Carolina
Charleston, South Carolina
Leslie R. Laufman, M.D.
Hematology Oncology Consultants
Columbus, Ohio
Constance A. Rufenbarger
Project Development
The Catherine Peachey Fund, Inc.
Warsaw, Indiana
Julia R. Scott, R.N.
President and CEO
National Black Women's Health Project, Inc.
Washington, DC
Daniel C. Sullivan, M.D.
Associate Professor of Radiology
University of Pennsylvania Medical Center
Philadephia, Pennsylvania
John H. Wasson, M.D., F.A.C.P.
Herman O. West Professor of Geriatrics
Center for the Aging
Dartmouth Medical School
Hanover, New Hampshire
Carolyn L. Westhoff, M.D., M.S.
Associate Professor
Obstetrics, Gynecology, and Public Health
Columbia University College of Physicians and Surgeons
New York, New York
Ruthann T. Zern, M.D., F.A.C.O.G.
Obstetrician/Gynecologist
Private Practice
St. Joseph's Hospital
Greater Baltimore Medical Center
Towson, Maryland
Back to Contents
Speakers
Freda E. Alexander, M.A., Ph.D., M.S.C.
"Basic Designs of Randomized Clinical Trials of
Screening"
Department of Public Health Sciences
The University of Edinburgh Medical School
Edinburgh, Scotland
Ingvar Andersson, M.D., Ph.D.
"The Malmo Mammographic Screening Trial: Update on Results
and a Harm-Benefit Analysis"
Department of Diagnostic Radiology
University Hospital of Malmo MAS
Malmo, Sweden
Cornelia J. Baines, M.D., M.S.C., F.A.C.E.
"Mammography Versus Clinical Examination of the
Breasts"
Associate Professor
Department of Preventive Medicine and Biostatistics
Faculty of Medicine
University of Toronto
Toronto, Ontario, Canada
Nils Bjurstam, M.D., Ph.D.
"The Gothenburg Breast Screening Trial: Results from 11
Years Followup"
Radiology Clinic Section of Mammography
NAL Hospital
Trollhattan, Sweden
Zora Kramer Brown
"A Breast Cancer Survivor's Perspective"
Founder and Chairperson
Breast Cancer Resource Committee
Washington, DC
Blake Cady, M.D.
"Detection and Treatment Trends: A Clinical Experience"
Professor of Surgery
Harvard School of Medicine
Interim Chief of Surgery
Surgical Oncology Division
Department of Surgery
Beth Israel Deaconess Medical Center
Boston, Massachusetts
Helena R. Chang, M.D., Ph.D., F.A.C.S.
"Screening for Breast Cancer in Younger Women Ages
40-49"
Surgeon and Director of the Hybridoma Laboratory
Associate Professor of Surgery and Pathobiology Program
Roger Williams Medical Center
Brown University
Providence, Rhode Island
Brian Cox, M.D., Ph.D., F.A.F.P.H.M.
"Variation in the Effect of Breast Screening by Year of
Followup"
Senior Research Fellow and Public Health Physician
Department of Preventive and Social Medicine
University of Otago Medical School
Dunedin, New Zealand
Harry J. de Koning, M.D., Ph.D.
"Quantative Interpretation of Age-Specific Mortality
Reductions from Trials by Microsimulation"
Assistant Professor of Public Health/Medical Technology
Assessment
Department of Public Health
Erasmus University
Rotterdam, The Netherlands
Stephen W. Duffy, M.Sc.
"Markov Models for Breast Tumor Progression: Estimates from
Empirical Screening Data and Implications for Screening"
Senior Scientist
MRC Biostatistics Unit
Institute of Public Health
University Forvie Site
Cambridge University
Cambridge, United Kingdom
Virginia L. Ernster, Ph.D.
"Increases in Ductal Carcinoma In Situ in Relation to
Mammography: A Dilemma"
Professor and Vice Chair
Department of Epidemiology and Biostatistics
Associate Director of the Cancer Center
School of Medicine
University of California, San Francisco
San Francisco, California
Stephen A. Feig, M.D.
"Radiation Risk"
Professor of Radiology
Jefferson Medical College
Director, Breast Imaging
Department of Radiology
Thomas Jefferson University Hospital
Philadelphia, Pennsylvania
Suzanne W. Fletcher, M.D., M.Sc.
"Breast Cancer Screening Among Women in Their Forties: An
Overview of the Issues"
Professor
Primary Care Division
Department of Ambulatory Care and Prevention
Harvard Medical School and Harvard Pilgrim Health Care
Department of Epidemiology
Harvard School of Public Health
Boston, Massachusetts
Jan Frisell, M.D.
"The Stockholm Mammographic Screening Trial: Risks and
Benefits"
Assistant Professor
Department of Surgery and Oncology
Stockholm South Hospital
Stockholm, Sweden
Paul Glasziou, M.B.B.S., Ph.D.
"The Quality and Interpretation of Mammographic Screening
Trials for Women Ages 40-49"
Senior Lecturer in Clinical Epidemiology
Department of Social and Preventive Medicine
University of Queensland Medical School
Herston, Queensland, Australia
Russell P. Harris, M.D., M.P.H.
"Variation of Benefits and Harms of Breast Cancer Screening
With Age"
Assistant Professor of Medicine
Division of General Medicine and Clinical Epidemiology and
Co-Director, Program on Health Promotion and Disease Prevention
University of North Carolina at Chapel Hill
School of Medicine
Chapel Hill, North Carolina
R. Edward Hendrick, Ph.D.
"Benefit of Mammography Screening in Women Ages 40-49:
Current Evidence from Randomized Controlled Trials"
Associate Professor and Chief
Department of Radiology
University of Colorado Health Sciences Center
Denver, Colorado
Karla M. Kerlikowske, M.D.
"Efficacy of Screening Mammography: Relative and Absolute
Benefit"
"Outcomes of Modern Screening Mammography"
Associate Director
Women Veterans Comprehensive Health Center
Veterans Affairs Medical Center
Assistant Professor
Department of Medicine, Epidemiology, and Biostatistics
University of California, San Francisco
San Francisco, California
Daniel B. Kopans, M.D., F.A.C.R.
"Problems with the Randomized Controlled Trials of Screening
and Inappropriate Analysis of Breast Cancer Data"
Associate Professor of Radiology
Harvard Medical School
Director of Breast Imaging
Department of Radiology
Massachusetts General Hospital
Wang Ambulatory Care Center
Boston, Massachusetts
Nancy C. Lee, M.D.
"Results from the National Breast and Cervical Cancer Early
Detection Program, 1991-1995"
Associate Director for Science
Division of Cancer Prevention and Control
Centers for Disease Control and Prevention
Atlanta, Georgia
Michael N. Linver, M.D., F.A.C.R.
"Mammography Outcomes in a Practice Setting by Age:
Prognostic Factors, Sensitivity, and Positive Biopsy Rate"
Director of Mammography
X-Ray Associates of New Mexico, PC
Clinical Associate Professor
Department of Radiology
University of New Mexico School of Medicine
Albuquerque, New Mexico
Anthony B. Miller, M.B., F.R.C.P.
"The Canadian National Breast Screening Study: Update on
Breast Cancer Mortality"
Director, National Breast Screening Study
Professor and Chairman
Department of Preventive Medicine and Biostatistics
University of Toronto
Toronto, Ontario, Canada
Maryann Napoli
"What Do Women Want To Know?"
Associate Director Center for Medical Consumers
New York, New York
Lennarth Nystrom
"Update of the Overview of the Swedish Randomized Trials on
Breast Cancer Screening With Mammography"
Biostatistician/Epidemiologist
Department of Epidemiology and Public Health
Umea University
Umea, Sweden
Eugenio Paci, M.D.
"Study Design II"
Epidemiology Unit
Center for the Study and Prevention of Cancer
Florence, Italy
Barbara K. Rimer, Dr.P.H.
"The Psychosocial Consequences of Mammography"
Director
Cancer Prevention, Detection, and Control Research
Cancer Control Department
Duke Comprehensive Cancer Center
Duke University Medical Center
Durham, North Carolina
Sam Shapiro
"Periodic Screening for Breast Cancer: The Health Insurance
Plan of Greater New York Randomized Controlled Trial"
Professor Emeritus Health Policy and Management
School of Hygiene and Public Health
Johns Hopkins University
Baltimore, Maryland
Edward A. Sickles, M.D., F.A.C.R.
"Screening Outcomes: Clinical Experience With Service
Screening Using Modern Mammography" Professor of Radiology
Chief
Breast Imaging Section
Department of Radiology
University of California Medical Center
University of California, San Francisco
San Francisco, California
Robert A. Smith, Ph.D.
"Screening Fundamentals"
Senior Director
Department of Cancer Control
American Cancer Society
Atlanta, Georgia
Laszlo Tabar, M.D.
"Recent Results from the Swedish Two- County Trial: The
Effects of Age, Histological Type, and Mode of Detection"
Associate Professor and Director Department of Mammography
Falun Central Hospital
Falun, Sweden
Back to Contents
Planning Committee
John K. Gohagan, Ph.D.
Chairperson
Chief
Early Detection Branch
National Cancer Institute
National Institutes of Health
Bethesda, Maryland
Jeffrey S. Abrams, M.D.
Senior Investigator
Cancer Therapy Evaluation Program
Division of Cancer Treatment, Diagnosis, and Centers
National Cancer Institute
National Institutes of Health
Bethesda, Maryland
Anne R. Bavier, M.N., F.A.A.N.
Deputy Director
Office of Research on Women's Health
Office of the Director
National Institutes of Health
Bethesda, Maryland
Frank Bellino, Ph.D.
Health Scientist Administrator
Biology of Aging Program
National Institute on Aging
National Institutes of Health
Bethesda, Maryland
Jerry M. Elliott
Program Management and Analysis Officer
Office of Medical Applications of Research
National Institutes of Health
Bethesda, Maryland
Virginia L. Ernster, Ph.D.
Professor and Vice Chair
Department of Epidemiology and Biostatistics
Associate Director of the Cancer Center
School of Medicine
University of California, San Francisco
San Francisco, California
John H. Ferguson, M.D.
Director
Office of Medical Applications of Research
National Institutes of Health
Bethesda, Maryland
Leslie G. Ford, M.D.
Associate Director
Early Detection and Community Oncology Program
Division of Cancer Prevention and Control
National Cancer Institute
National Institutes of Health
Bethesda, Maryland
Leon Gordis, M.D.
Conference and Panel Chairperson
Professor
Department of Epidemiology
School of Hygiene and Public Health
Associate Dean for Admissions and Academic Affairs
School of Medicine
Johns Hopkins University
Baltimore, Maryland
William H. Hall
Director of Communications
Office of Medical Applications of Research
National Institutes of Health
Bethesda, Maryland
Douglas B. Kamerow, M.D., M.P.H.
Director
Office of the Forum for Quality and Effectiveness in Health Care
Agency for Health Care Policy and Research
Rockville, Maryland
Daniel B. Kopans, M.D., F.A.C.R.
Associate Professor of Radiology
Harvard Medical School
Director of Breast Imaging
Department of Radiology
Massachusetts General Hospital
Wang Ambulatory Care Center
Boston, Massachussetts
Barnett S. Kramer, M.D., M.P.H.
Deputy Director
Division of Cancer Prevention and Control
National Cancer Institute
National Institutes of Health
Bethesda, Maryland
Amy S. Langer, M.B.A.
Executive Director
National Alliance of Breast Cancer Organizations
New York, New York
Elaine Lee
Program Analyst
Planning, Evaluation, and Analysis Branch
National Cancer Institute
National Institutes of Health
Bethesda, Maryland
Nancy Lee, M.D.
Associate Director for Science
Division of Cancer Prevention and Control
Centers for Disease Control and Prevention
Atlanta, Georgia
Carl M. Mansfield, M.D., D.Sc., F.A.C.R., F.A.C.N.M.
Associate Director
Radiation Research Program
Division of Cancer Treatment, Diagnosis, and Centers
National Cancer Institute
National Institutes of Health
Bethesda, Maryland
Anthony B. Miller, M.B., F.R.C.P.
Director,
National Breast Screening Study
Professor and Chairman
Department of Preventive Medicine and Biostatistics
University of Toronto
Toronto, Ontario, Canada
Sue Moss, Ph.D.
Cancer Screening and Evaluation Unit
Section of Epidemiology
Institute of Cancer Research
Sutton, Surrey, England
Nancy Nelson
Science Writer
National Cancer Institute
National Institutes of Health
Bethesda, Maryland
Gillian Newstead, M.D.
Director of Breast Imaging
Breast Imaging Center
New York University
New York, New York
Cherie Nichols, M.B.A.
Chief
Planning, Evaluation, and Analysis Branch
National Cancer Institute
National Institutes of Health
Bethesda, Maryland
Vivian W. Pinn, M.D.
Director
Office of Research on Women's Health
Office of the Director
National Institutes of Health
Bethesda, Maryland
Alan Rabson, M.D.
Deputy Director
National Cancer Institute
National Institutes of Health
Bethesda, Maryland
Barbara K. Rimer, Dr. P.H.
Director
Cancer Prevention, Detection, and Control Research
Cancer Control Department
Duke Comprehensive Cancer Center
Duke University Medical Center
Durham, North Carolina
Sam Shapiro
Professor Emeritus
Health Policy and Management
School of Hygiene and Public Health
Johns Hopkins University
Baltimore, Maryland
Edward A. Sickles, M.D., F.A.C.R.
Professor of Radiology
Chief
Breast Imaging Section
Department of Radiology
University of California Medical Center
San Francisco, California
Robert A. Smith, Ph.D.
Senior Director
Department of Cancer Detection and Treatment
American Cancer Society
Atlanta, Georgia
Edward Sondik, Ph.D.
Director
National Center for Health Statistics
Centers for Disease Control and Prevention
Hyattsville, Maryland
Laszlo Tabar, M.D.
Associate Professor and Director
Department of Mammography
Falun Central Hospital
Falun, Sweden
Robert E. Tarone, Ph.D.
Mathematical Statistician
Division of Cancer Epidemiology and Genetics
National Cancer Institute
National Institutes of Health
Bethesda, Maryland
Rosemary Yancik, Ph.D.
Chief
Cancer Section
Geriatrics Program
National Institute on Aging
National Institutes of Health
Bethesda, Maryland
Back to Contents
Conference Sponsors
National Cancer Institute
Richard Klausner, M.D.
Director
Office of Medical Applications of Research, NIH
John H. Ferguson, M.D.
Director
Conference Cosponsors
National Institute on Aging
Richard J. Hodes, M.D.
Director
Office of Research on Women's Health, NIH
Vivian W. Pinn, M.D.
Director
Centers for Disease Control and Prevention
David Satcher, M.D., Ph.D.
Director
Back to Contents
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