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Editorial
July 21, 2016
The article by Esselen et al1 in this issue of JAMA Oncology
belongs to the category of health services research that asks how the
introduction of new evidence influences clinical practice. In the
instance they examined—publication of a study that showed routine cancer
antigen 125 (CA-125) surveillance was harmful—the answer seems to be
“not at all.” In the 6 NCI-designated cancer centers they studied, the
use and frequency of CA-125 testing of women in remission after initial
treatment for ovarian cancer was similar in the years before and after
the study. In both periods, almost all such patients received CA-125
testing approximately every 3 to 4 months. This is actually quite a
remarkable observation. Why did practice not change?
It is instructive to reread the original study by Rustin et al2,3
that questioned the use of CA-125 testing. It was a well-conducted
multicenter randomized trial of 529 women who were in remission after
initial chemotherapy for ovarian cancer. All patients received CA-125
testing every 3 months, but the treating physicians did not know the
results. If and when a CA-125 test exceeded twice normal, patients were
randomized into what they called early and delayed treatment groups,
with randomization stratified by several prognostic factors. For
patients in the early treatment group, their physicians were notified of
the CA-125 results. In the delayed treatment group the results were
withheld, and any decisions about further treatment were based on
clinical recurrence. Most women in the early treatment group started
chemotherapy soon after the notification of elevated CA-125 results.
Those in the delayed treatment group started about 5 months later.
Median survival was not different: 25.7 months in the early treatment
group vs 27.1 months in the delayed treatment group. However, median
time to deterioration in global health score or death was significantly
longer in the delayed treatment group (5.8 vs 3.2 months, P =
.002). The delayed treatment group also underwent fewer cycles of
chemotherapy, were less likely to receive third-line chemotherapy, and
had 5 more months to live in remission after their initial treatment.2,3
The
question for discussion then becomes: why was there no change in
practice in response to good evidence? It is not as if physicians are
incapable of rapid change in practice in the face of new information. It
happens all the time when the information favors new or more treatment.4,5
For example, we assessed change in practice associated with the report
showing a 2% absolute survival improvement at 18 months with taxane plus
doxorubicin compared with doxorubicin alone in breast cancer patients
with positive nodes. The oral report6
of these results in 1998, 5 years before the actual publication of the
trial, was associated with a rapid shift to taxanes with a more than
doubling in use within 3 months.5
Why
did this not occur with the Rustin study? One could argue that there
was no change because the clinical guidelines did not change. This is
somewhat circular, because the 6 centers studied by Esselen et al1 were leading academic medical centers, populated by clinicians who also sit on the committees that write the guidelines.
I
will propose 2 sets of factors contributing to the lack of an obvious
change in practice in response to the Rustin study. The first relates to
the fundamental attractiveness of testing, and the second involves how
the Rustin study was framed by the authors and subsequent commentators.
Physicians
practice in a sea of uncertainty. Making life-altering decisions based
on incomplete information is 1 of the major stresses of becoming a
physician. There are good and bad ways of dealing with that stress. Over
confidence is 1 bad way. We all have encountered physicians who
practice a “my way or the highway” style. A more acceptable means to
reduce uncertainty is to seek more information through testing. The past
2 decades have witnessed a proliferation of new cancer tests and
improvements in older ones. Highly sensitive scans and molecular and
genetic markers allow us to more accurately characterize risk for or
extent of disease and response to treatment, reducing uncertainty in
decision making.
As
the tests proliferated, questions arose whether more information is
always a good thing. Magnetic resonance imaging for uncomplicated low
back pain can lead to unnecessary surgery.7 After routine fetal monitoring was introduced, childbirth became a surgical procedure for a quarter of women.8 The dissemination of prostate-specific antigen screening was followed by an iatrogenic epidemic of prostate cancer.9,10
This
is a difficult message to accept. How can more information possibly
hurt? Avoiding information sounds antiscientific. Can we not still
obtain the information but interpret it more wisely? A nice sentiment,
but it lacks evidence of feasibility in real life. The analyses by
Esselen et al1 suggest that information on increased CA-125 drove initiation of second line chemotherapy as rapidly after the report2,3 by Rustin as before.
Another
difficulty involves telling physicians that they may be doing the wrong
thing. Whether it involves tests or treatments, it is no easy task to
convince physicians that they are causing more harm than good. There are
a number of predictable responses to reports such as the 1 by Rustin et
al2,3
One is what I call the moving target. “Okay, so that surgery (or
radiotherapy or whatever) had bad outcomes, but you don’t understand
that the techniques have improved dramatically since the time of your
data.” Such a response has the advantage of sometimes being true. Other
responses include questioning the patient selection: “Those aren’t the
people I see in my practice” or the physicians studied: “No wonder it
didn’t work. I don’t do it that way!”
All 3 of these responses and more greeted the Rustin study.11,12
What did not occur was any change in practice. Readers might want to
conduct a thought experiment to ask themselves: “What if the results
reported for delayed treatment were found instead for a new chemotherapy
regimen? How would the report have had an effect on practice?”
The second set of reasons has to do with framing the results of the Rustin study. The 2 approaches studied by Ruskin et al2,3
were characterized as early vs delayed treatment, but that was not what
they studied, at least not in my opinion. They were in essence
comparing CA-125 surveillance every 3 months vs no testing. The “no
testing” group received CA-125 testing, but since the results were not
released to the physicians, it was the same as not testing. The findings
of the study are then best framed as routine surveillance with CA-125
testing is harmful in patients diagnosed with ovarian cancer in
remission after initial treatment.
Another
factor that impedes clear thinking about harmful tests and treatments
is the injection of medical economics into the discussion. Discussions
of cost-effectiveness can make clinicians uncomfortable. The results of
cost-effectiveness analyses can vary widely depending on the
assumptions. And why should physicians act as societal financial
gatekeepers? It is difficult enough helping patients decide on what is
best for them without introducing the concept of what is best for
society. In addition, such discussions can be seen by our patients as
attempts at rationing their care. The suspicion that other patients,
perhaps those with better insurance or better connections, might be
receiving better treatment can destroy trust in the physician.
But
in the context of CA-125 testing, the issue of cost-effectiveness
becomes absurd. How can a test or treatment be cost-effective if it is
not effective —indeed, if it is harmful? Thus, I am uncomfortable with
the focus on the economic impact of continued CA-125 testing by Esselen
et al.1
It is not by any means irrelevant, but it muddies the issue. Once
again, the findings of the Ruskin study are that routine surveillance
testing is harmful. That should be the focus for subsequent decisions by
clinicians, payers, and policy makers—not the costs involved.
And,
of course, the women with ovarian cancer contribute to the decisions to
obtain C-125 testing. While physicians may be challenged dealing with
uncertainty, many of our patients refuse absolutely to tolerate it. They
want to know, even if that knowledge can lead to harm. Thus, in a
shared decision making context, most patients will choose more
information.13
But why would clinicians present the option of CA-125 testing? Shared
decision making does not require that physicians present the patient
with harmful options. We do not discuss heart transplants with patients
who have mild congestive heart failure. Why would we discuss CA-125
testing with women who have ovarian cancer in remission?
Will
the practice of obtaining routine CA-125 testing change? I doubt it.
The moving target argument is too strong. There will be better tests,
and more effective treatments. And studies like that of Rustin with
uncomfortable results are usually not replicated.14 The issue is allowed to fade away. The fatal attraction of more information is too compelling.
References
Esselen
KM, Cronin
AM, Bixel
K,
et al. Use of CA-125 tests and computed tomographic scans for
surveillance in ovarian cancer [published online July 21, 2016]. JAMA Oncol. doi:10.1001/jamaoncol.2016.1842.
Rustin
GJ, Van Den Berg
ME. A randomized trial in ovarian cancer (OC) of early
treatment of relapse based on CA125 level alone vs delayed treatment
based on conventional clinical indicators (MRC OV05/EORTC 55955 trials).
ASCO Ann Meet Proc. 2009;27(18s):1.
Rustin
GJ, van der Burg
ME, Griffin
CL,
et al; MRC OV05; EORTC 55955 investigators. Early versus delayed
treatment of relapsed ovarian cancer (MRC OV05/EORTC 55955): a
randomised trial. Lancet. 2010;376(9747):1155-1163.
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Jackevicius
CA, Anderson
GM, Leiter
L, Tu
JV. Use of the statins in patients after acute myocardial infarction: does evidence change practice? Arch Intern Med. 2001;161(2):183-188.
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SH, Duan
Z, Kuo
YF, Hortobagyi
GN, Freeman
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JS. Impact of a scientific presentation on community treatment patterns for primary breast cancer. J Natl Cancer Inst. 2006;98(6):382-388.
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Henderson
IC, Berry
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GD,
et al. Improved disease-free and overall survival from the addition
of sequential paclitaxel but not from the escalation of doxorubicin
dose in the adjuvant chemotherapy of patients with node-positive primary
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Webster
BS, Cifuentes
M. Relationship of early magnetic resonance imaging for
work-related acute low back pain with disability and medical utilization
outcomes. J Occup Environ Med. 2010;52(9):900-907.
PubMed | Link to Article
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Placek
PJ, Taffel
SM, Moien
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PubMed | Link to Article
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Welch
HG, Albertsen
PC. Prostate cancer diagnosis and treatment after the introduction of prostate-specific antigen screening: 1986-2005. J Natl Cancer Inst. 2009;101(19):1325-1329.
PubMed | Link to Article
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Howrey
BT, Kuo
YF, Lin
YL, Goodwin
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PubMed | Link to Article
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Morris
RT, Monk
BJ. Ovarian cancer: relevant therapy, not timing, is paramount. Lancet. 2010;376(9747):1120-1122.
PubMed | Link to Article
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Rustin
G, van der Burg
M, Griffin
C, Qian
W, Swart
AM. Early versus delayed treatment of relapsed ovarian cancer. Lancet. 2011;377(9763):380-381.
PubMed | Link to Article
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Markman
M, Petersen
J, Belland
A, Burg
K. CA-125 monitoring in ovarian cancer: patient survey
responses to the results of the MRC/EORTC CA-125 Surveillance Trial. Oncology. 2010;78(1):1-2.
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