January 21-23, 1997
(In press-3/20/97)
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
Back to Contents
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:
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?
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?
Are there other benefits?
If so, what are they? How do they change with age?
What is known about
how the benefits and risks of breast cancer screening differ based on known
risk factors for breast cancer?
What are the directions for future research?
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.
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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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