by C.A. Wolski
Five issues continue to trouble radiology in its endeavor to provide mammography services to an increasingly demanding public.
More than any other imaging procedure, mammography has given
radiology a public face. Public service advertisements on
television, on radio, and in print urge women to get a yearly
mammogram. Lawmakers have recognized mammography's value by passing
legislation guaranteeing Medicare recipients access to the
procedure.
With this high profile, however, come the challenges and
criticism associated with any very-public endeavor. Though mandated
by Congress, mammography remains woefully under-reimbursed by
insurers and the Centers for Medicare & Medicaid Services
(CMS). Mammographers are the most sued specialists in radiology,
affecting both morale and access. And, in a score of reports over
the last year, the media has questioned both the effectiveness of
mammography and the radiologists who administer it.
These very public trials reflect the controversies raging within
the specialty, including the issues of subspecialization, the
shrinking pool of mammographers, reimbursement, new technology, and
the overselling of mammography. And while radiologists and,
specifically, mammographers agree that these are problems, they
disagree on how to solve them.
Issue No. 1: Subspecialist vs Generalist Readers
In the September issue of Radiology, University of
California-San Francisco (UCSF) Medical Center radiologists Edward
A. Sickles, MD, and Dulcy E. Wolverton, MD, and Katherine E. Dee,
MD, now at the Department of Radiology at the University of
Washington Medical Center, Seattle, reported that radiologists
specializing in mammography recognized more cancers, particularly
early stage cancers, and had lower recall rates than general
radiologists.
The study involved more than 47,000 screening and more than
13,000 diagnostic mammographic examinations. In general,
mammographers were almost twice as likely to detect a cancer than a
generalist. The study also found that recall rates for
mammographers were much lower, 4.9%, compared to generalists, 7.1%.
And though it may be safe to assume that specialization is the
answer, lead author Sickles, who is a professor of radiology and
section chief of breast imaging at the UCSF, is quick to point out
that his study can only be considered preliminary, and not the
final word on the issue.
And though specialization might make sense in large urban areas
like San Francisco, in smaller markets or in smaller groups, it may
not be practical. "Subspecialization, like any systems paradigm,
has its advantages and disadvantages," says R. James Brenner, MD,
JD, director of breast imaging at the Eisenberg Keefer Breast
Center, Tower-St Johns Imaging in Santa Monica, Calif, and clinical
professor of radiology at UCLA. "Advantages usually can be
successfully engaged in [within] a larger group where volume and
resource allocation can be matched. All systems require some
redundancy to account for vacation time and other
off-the-front-line responsibilities. When one becomes too
subspecialized, then that person's contribution to redundancy in
the system is compromised."
Though subspecialization is an attractive ideal, it could also
compromise patient access, says Valerie P. Jackson, MD, FACR, John
A. Campbell Professor of Radiology, residency program director, and
chief of breast imaging at the Indiana University School of
Medicine, Indianapolis. "Subspecialization would undoubtedly
improve the accuracy of mammography," she says. "However, the
tradeoff would be decreasing access because there are already too
few radiologists who subspecialize in mammography and we can only do so
many cases."
She also cautions that solutions such as double reading and the
use of computer aided detection (CAD) systems have their own set of
limitations. "Double reading has been shown to improve detection
of cancer, sometimes at the expense of a higher false-positive
rate, but not always[it] depends on how the double reading is
handled," she says. "However, with the manpower shortages we have,
it becomes very difficult, if not impossible, to have double
reading in many practices. CAD systems have been shown to pick up
additional breast cancers missed by radiologists, but they often
lead to much higher false-positive ratesespecially when used by
radiologists who don't have the confidence or experience to throw
out' the many false-positive areas that get flagged with CAD."
Subspecialization could have other benefits. It can be an easy
way to build the group's local profile and decrease legal
liability, says Brenner. However, even with the benefits it affords
large groups, he admits, subspecialization could have a downside.
"Some radiologists are reluctant to surrender any skills, for fear
of future employment opportunity restrictions," he says.
But with all the benefits subspecialization could bring,
particularly in higher accuracy rates and less legal liability,
there is the question of where these specialists will come
from.
Issue No. 2: The Case of the Vanishing Subspecialty
Radiology as a whole, and mammography in particular, is facing a
severe and well-documented manpower shortage. According to the
American College of Radiology (ACR), this shortage may take up to
10 years to correct even if additional slots can be created for
radiology residents. The shortage is not a product of a lack of
interest on the part of medical studentsradiology is one of the
most popular specialties among residentsbut funding caps. "The caps
are actually just put there," says Ellen B. Mendelson, MD,
professor of radiology and chief of the Breast Imaging Section,
Northwestern University Medical School/Northwestern Memorial
Hospital Lynn Sage Comprehensive Breast Center, Chicago. "CMS will
not reimburse facilities beyond the caps that have been set. It's a
complicated thing. They're imposed on all residency positions. What
facilities look for is some sort of economic aid in supporting
their training program. And money comes from the federal government
to support the education of physicians in training."
According to Mendelson, schools can offer as many slots as they
want. It is all a matter of funding. Residency stipends, which
include salaries and health benefits, average about $60,000. "We
can try to find funding," she says. "There are so many regulations
and so many stipulations right now. We can apply for more help.
Will [the government] come through? It's possible, we don't know."
Mendelson and her colleagues are currently in the process of
evaluating 300 applicants for seven radiology residency positions
for 2004.
The shortage of mammographers not only is a result of too few
slots, but also has been caused by a lack of incentives to enter
the specialty. "The disincentives derivative of the current
economic climate for breast imaging is likely to affect
[residents'] decisions," says Brenner. "So, as a secondary
consequence, the lack of incentives to go into breast imaging may
have a negative impact on access to mammography, in terms of both
specialty selection, as well as group or institutional commitment
to increasing resource allocation."
This lack of incentive is primarily a function of mammography's
low reimbursement rates and high stress level, which is caused by
its high legal liability. "Unless we solve the reimbursement and
medicolegal problems associated with breast imaging, we are
unlikely to attract residents into the field and women's access to
mammography will be further compromised," says Jackson.
Issue No. 3: Who Should Pay?
Perhaps the most contentious issue facing mammography is who
should pay for the procedurethe government, insurers, or
patients.
For Brenner, when mammography became a public mandate, the die
was cast, so public monies have to be used to support the
specialty. "To underfund the mandate [will result in a de facto]
tax on providers," he says. "Actual cost surveys have indicated
that reimbursement is grossly inadequate at health care
institutions. These are not only the very venues where most
Medicare beneficiaries receive their care, but are the ones that
serve as training centers for future breast imaging specialists. To
ignore such costs for a population designated to receive the
benefits of the program is tantamount to abandoning the commitment
that Congress has made. Lip service to providing mammography to the
population in this country is no substitute for adequate
reimbursement. Those who seek to divert funds from a proven
technology [such as mammography]and there remain a minority who
contend that the benefits are not sufficiently provento elusive
targets of investigation sometimes emerge from those who were not
benefited by the technology. It is somewhat ironic that outcome
goals for more expensive [procedures, such as] chemotherapy are far
below benchmarks for mammography, though the controversy continues
to haunt the latter, and not the former."
Mendelson's outlook on the problem of reimbursement spells doom
for the public mandate Brenner talks about. Instead of seeing
greater access to mammography, Mendelson speculates that there
could be decreasing access with groups such as several in New York
City offering mammograms as a cash-only, nonreimbursed examination.
"The groups in New York that have taken themselves out of the
reimbursement cycle are doing just fine; if you are providing
services to people whose incomes are high and who have the ability
to pay, there's no reason to reduce the cost to those people," she
says. "Somebody who pays $120 to go and have their hair colored and
cut can afford to pay $375 for a mammogram. For those people for
whom mammogram costs are a hardship, will it impair access?
Probably."
But this dire scenario of examinations only for a wealthy elite
may not come to pass. Some believe that high-quality, efficient,
and affordable mammography could be realized through the efficiency
of a new generation of digital imaging equipment.
Issue No. 4: Is the New Digital Technology Worth the Cost?
In the September issue of the American Journal of Roentgenology,
John Lewin, MD, et al reported that both digital and film
mammograms showed cancers the other format missed. Film was
slightly better, but the difference was statistically
insignificant. The advantage for digital mammography over
conventional film mammography is efficiency, according to Lewin, an
associate professor and codirector of breast imaging at the
University of Colorado Health Sciences Center, Denver. "The value
of digital is not going to be in terms of finding more cancers at
screening, no more than the value of computed radiography for the
chest is in finding more lung cancers," he says. "The value of
going digital is in terms of functionalityelimination of film and
processors, digital archiving, unlimited copies, electronic image
transfer. Technologists can process patients faster on digital than
on film, so throughput per machine is increased. Also, while my
study looked only at screening, digital magnification viewsused in
diagnostic mammography, not screeningin my opinion, are superior to
those taken on film."
Michael Linver, MD, director of mammography for X-Ray Associates
of New Mexico, Albuquerque, and associate professor of radiology at
the University of New Mexico, sees a bright future for digital
mammography, with its ability to leverage resources by transmitting
studies to outside mammographers. But, he says, its efficiency and
cost-benefits have not yet been realized. "Right now, it's still
too expensive," he says. "The workstations are still so badly
designed, they're not very efficient to use. Given the small
reimbursement, time becomes a critical issue. You can't be
efficient the way the current workstations are set up, plus the
machine is just too expensive; it costs you around $800,000 to set
up one machine with a workstation with all the bells and whistles.
[However,] I think competition will drive that down."
But even when the technical problems are solved, the promise of
efficiency and lower cost of the technology may still not make it
practical. "Whether or not mammography is worth it depends on your
setup, including your patient volume, the relative costs of
technologists, floor space, machines, and how many film units you
would have to replace," says Lewin.
No matter how advanced or efficient the technology, it is still
only as good as the mammographer making the interpretation. "What
we found in our study was that any difference in technology is
obliterated by the variability in reading by the radiologist and by
random effects of positioning by the technologist, so human factors
are key," says Lewin. "Other studies have shown that just under
half of the cancers missed by mammography are detectible in
retrospect and the others are not visible, so clearly there is room
for improvement on both sides. CAD may help the interpretation
side. The technical side may require some major change from the
mammography paradigm of a single radiograph of a compressed breast
before a noticeable improvement can be made."
Identifying a quality reading may be as difficult as developing
a new technology. "How do you train people to do a better job? Some
of it is just experience," says Linver. "Even if you know what
you're doing and do it well, if you don't do it all the time, you
lose those skills. That's why I think a certain minimum number
should be required at a much higher level than it is now." Linver
adds that an effective, high-volume practitioner would be reading
at least 3,000 studies a year.
Issue No. 5: Is the Modality Worthy?
Fundamental to the controversies facing mammography is whether
it is as effective as it claims to be. For Leonard Berlin, MD,
FACR, chairman of the Department of Radiology, Rush North Shore
Medical Center, Skokie, Ill, mammography has promised more than it
can deliver. This is reflected in rising insurance and lawsuit
rates. "On one hand, if you look at the last decade, we see a
continuing rise in malpractice litigation, [but] as far as conduct
of radiologists goes, the American College of Radiology and other
professional organizations have worked very hard to increase the
performance of radiologists," he says. "I don't think that anybody
can doubt that radiologists in 2002 do a better job reading
mammograms than they did 5 and 10 years ago. In spite of that, the
number of suits and severity of suits increasewhy? Obviously, there
are only two things that can cause an increase in litigation:
negligence of the doctor or the injury caused. And the negligence
hasn't increased; if anything, it's gotten better. Therefore, let's
focus on the injury to the patient and my thesis is that our
success in promoting mammography by emphasizing its values has
strengthened the injury cause more than our success in reducing
radiologic errors. We've reduced radiologic errors, but the
promotion we've done on mammography as far as establishing its
efficacy is far greater than our ability to decrease the
errors."
Berlin says that statistical studies, which have been widely
circulated in professional journals and the news media, have
muddied the waters, usually for the worst. "If you ask whether the
early diagnosis of breast cancer reduces mortality, as some
commentators have said, that remains one of the most disputed
issues in medicine today," he says. "It's intuitively obvious, but
it remains markedly resistant to scientific validation. There have
been a number of articles on both sides in the scientific
literature. There are various statistical biaseslead time bias,
length bias. It all tends to skew the survival figures. There was
an article in the New England Journal of Medicine 2 years ago that
reviewed 63 articles between 1995 and 1997 on statistical errors;
they found 48% of the articles had mistakes in how they calculated
the statistics."
The result of all of these contradictory reports and inflated
statistics is misinformation and fear, which has been exploited by
the media. "There was a survey published in the New York Times in
January '01 -40% of women feared dying of breast cancer, but
only 4% of them do; 4% of women have a fear of dying of heart
disease and 36% of them dothese are the misperceptions," says
Berlin. "There's a study out of Dartmouth University, a survey of
women, and they overestimated dying of breast cancer by 20-fold;
they overestimated the value of screening mammography in reducing
this risk by 100-fold."
The answer to the statistical bias that has resulted in the
overselling of mammography is simple: honesty. "We have to tell the
truth to the American public that there are controversies out
there; that we don't know the absolute truth," says Berlin, who
describes himself as pro-mammography. "I think we will never know
the absolute truth, because no matter what statistical study is
done, there are always flaws in the study. There is no proof that
mammography does not save lives, and until or unless there's proof
that it doesn't save lives, then I think we have to recommend
mammography."
Berlin has already begun his campaign to get the truth out,
introducing a resolution at the September ACR meeting. "The
American College of Radiology, while it should continue to support
and recommend mammography, should nevertheless undertake a public
relations campaign that accurately informs the public about the
pros and cons of mammography," he says. "Yes, they should still
recommend it, but they should tell the truth about mammography,
tell both sides of the mammography situation, and encourage women
to have mammography, but in the last analysis, a woman has to
decide for herself."
The public relations campaign is necessary, says Berlin, because
mammography is here to stay and will continue to be provided in the
same way it is now until science can offer something completely
differentsuch as molecular studies or a blood test similar to the
one used in prostate cancer screenings.
For all of his qualms about the effectiveness of mammography,
Berlin is supportive of it. "Let's look at mammography as an
opportunity to find your breast cancer early, and let's look at it
as a good opportunity for a cure," he says.
What's the Answer?
There is no dispute among radiologists as to the value of
mammography. Even those most critical are dedicated to their
specialty. If there is one common theme linking the most pressing
issues, it is funding. Without it, there will be no mammographers
to provide the tests that millions of women rely on for their
continued good health. As Mendelson points out, "We value
mammography, but we don't want to pay for it." Without the
financial incentive to lure the best and the brightest,
Congressional legislation notwithstanding, more and more residents
will enter other, more lucrative fields of medicine and radiology.
The question of where this money should come from will probably
continue to fuel the debate and be as dependent on political and
philosophical outlook as economic and medical realities.
As Berlin suggests, the ultimate future of breast health may lie
outside the realm of mammography. A recent report in the
Proceedings of the National Academy of Sciences may prove him to be
prescient. The publication issued findings by researchers at Cold
Spring Harbor Laboratory in New York and the University of
Washington-Seattle who have found a breast cancer gene that could
aid in detection of breast and other cancers.
C.A. Wolski is associate editor of Decisions in Imaging Economics.