THE STATE OF CANCER RESEARCH
HEARING BEFORE THE SUBCOMMITTEE
ON HEALTH AND ENVIRONMENT OF
THE COMMITTEE ON COMMERCE HOUSE
OF REPRESENTATIVES ONE HUNDRED FIFTH CONGRESS
SECOND SESSION JULY 20, 1998
SERIAL NO.105-128
(The following represents a portion of the
above-named transcript, which appears on pages 29-32. At this hearing,
Congressman Tom Coburn, M.D. of Oklahoma questioned Dr. Edison Liu,
Director, Division of Clinical Sciences, National Cancer Institute.
Congressman Coburn accused the NCI of misleading the public
and of "selectively releasing data" about the abortion-breast
cancer link. The NCI’s web site at the time of this hearing had this to
say about the abortion-breast cancer link on its page entitled, Cancer
Facts, National Cancer Institute, National Institutes of Health, Abortion
and Breast Cancer: "Although it has been the subject of extensive
research, there is no convincing evidence of a direct relationship between
breast cancer and either induced or spontaneous abortion. Available data
are inconsistent and inconclusive, with some studies indicating small
elevations in risk, and others showing no risk associated with either
induced or spontaneous abortions. The scientific rationale for an
association between abortion and breast cancer is based on limited
experimental data in rats, and is not consistent with human data."
According to Dr. Joel Brind, President of the Breast
Cancer Prevention Institute, this last statement is "an outright
lie." The statement has since been removed from
the NCI web site.
Mr. Coburn: Thank you. And thank you so much for
staying and taking time to answer my questions.
I really want to deal just really in one area, and I am
really concerned about it, and it really doesn’t
have to do with just you all. I have been on Congress
4 years now, and I oftentimes have seen pressures brought to bear to
have a result when, in fact, all of us, both me and you, I
think, want to see the best science that we can for
this country.
And I know that the epidemiologic research that you all
have sponsored, both in-house and out-house, have
been directed toward finding causative factors. And
I am going to vary into a little area that is controversial with
you, because not only do I want to find the answer, but maybe you can
educate me why I am wrong on this.
I have gone through and looked at some 31 studies on the
risk of breast cancer and induced abortion, and I
have also read the Web page put out by the NIH, and
I must tell you I am astounded at what I see on the Web page versus
actually personally as a physician reading the studies that
have been put forward on the risk of induced
abortion increasing the risk of breast cancer in our
population.
And what I really want to do is just kind of go back and
forth a little bit so you can change my mind and
educate me on why I am so wrong as I read these
studies and why NIH, to me, seems to have taken a position that is not
in the best interests of the women in this country in terms
of risk. And so what I would like to do is just to
kind of go through and let you dissuade me of the
fact that it is true that there have been 12 studies on the
risk of breast cancer and induced abortion in this country? Mr.
Liu: Well, Dr. Coburn, I think I personally wasn’t prepared to go
through every single study at this point, so I can’t
answer the specifics of your questions, and I think
that we will be happy to put on the record an appropriate
response to them.
I can tell you that in tracking the studies all along,
in my prior life before coming to the NCI, I was
also a member of the department of epidemiology at
the University of North Carolina at Chapel Hill, and we did discuss this
in our faculty discussions, because it was a very important topic
for obvious reasons. I can tell you for sure that at least within the
National Cancer Institute, we would not hide nor guide any
solution to a problem that the data would not show
one way or the other. And if there is some
ambiguity, then I think it is our responsibility to lay on the table
that ambiguity.
Mr. Coburn: Well, then answer me the question why
the NCI has not released the data on the Asian
American study that was prepared in the British Journal of
Cancer, which you all had something to do with. Well, you released the
data for only a portion of the women in that study so that
everybody in the country could look at it. In other
words, part of the data that showed a correlation
between the risk of breast cancer and induced abortion, you all didn’t
release. You selectively released the data. And that is the thing that
concerns me about it is that you have not released all the data on a lot
of the studies that you all have, in fact, paid for with
taxpayers’ money. What we all want is the answer
to the question. And I am not trying to say that
somebody is right and somebody is wrong, but when we see a Web page
that is -- to me is not scientifically driven on this
issue, and is more politically driven based on --
there are 35 studies worldwide, I think, that is
correct on this issue, and -- although some are small. And there are
some, there is no question that there is a look-back bias
in them. But there is also some that there is not a
bias, and you have to assume in those where there is
a bias that somebody would claim to have an abortion.
There is also a study using a zero for cervical cancer
to look to see if there was a bias, and that was in
the study by Dr. Darwin where she checked to see if
there was a bias, and she checked that, or he checked that, I can’t
recall which, the gender of the doctor, looking at cervical
cancer risk with a look-back bias as well. And in
fact, they showed none, and had there been a bias,
it would have been a 50 percent increase in cervical cancer.
So I guess the question that I am raising for you all is
that it is incumbent that nobody with a political
agenda one way or the other can look at NIH’s Web
site and said that you all weren’t anything but fully exposing all
of the data. And I guess my question and my worry is when you read that,
having read many of the studies, and when I read your Web
page, what I find is what seems to be a bias for
lack of what the facts are.
And what it says is -- if I am correct -- is that there
is only one study that was prospective in the United
States, in other words, had no reporting bias, if I
am correct, and it showed a 90 percent risk increase with induced abortion,
and yet we don’t see that data on the Web sites. And so I guess what --
I guess my question for you is -- is how do we put the data out from
the NIH so that if somebody is far to the right of what is
really accurate and saying that there is a risk of
induced abortion, that they can’t claim -- your
credibility can’t be undermined by how you put that data out. I guess
that is what I am really asking.
I have a difference of what I see in the data, and I am
not a trained epidemiologist. So my opinion is not
as valuable as a trained epidemiologist is. But I
think it is incumbent upon you to -- how do we change that data on the
Web site so that it does not look biased?
Mr. Liu: Dr. Coburn, I have to admit my ignorance
in terms of that Web-site-specific section, so I
think if you will allow us to explore this a little
more carefully and then have an opportunity to discuss with you on a
more equal basis, then I would be happy to either myself or
one of the other ---
Mr. Coburn: If the chairman would allow that, and
we can do that and look at that Web site together.
And also, if I would submit for the record some
questions to go along with that that you might answer for me, I would
very much appreciate it. I really feel that you can
convince me different than what I have seen. I just
want that reassurance and to be convinced.
Mr. Liu: Absolutely. And I think it is important
for us to provide you with that.
Mr. Whitfield: Without objection.
Mr. Ganske: Would the gentleman yield?
Mr. Coburn: I would be happy to yield.
Mr. Ganske: I always wondered on this issue why
there would be, if there is any, a difference
between a spontaneous abortion and an induced abortion? I
mean would not the biology be the same?
Mr. Coburn: Absolutely not. A spontaneous
abortion is associated with a much lower levels of
estrogen, whereas an induced abortion is not. And we know
estrogen and high levels of unopposed estrogen do have risk factors for
breast cancer.
Mr. Ganske: Dr. Liu, do you have any comment on
that?
Mr. Liu: You know, the problem with spontaneous
abortion ---
Mr. Ganske: Because isn’t this part of the
sampling, a problem with trying to come up with
that? Do the studies show ---
Mr. Whitfield: If I may just interrupt for 1
minute. I am going to give you 5 more minutes on
this because some of the second panel, like Dr. Chang from
Los Angeles, has surgery in the morning that she must conduct. So if we
have another 5 minutes, and, Dr. Ganske, you have the
floor.
Mr. Ganske: Dr. Chang probably could help in this
discussion. But when these epidemiologic studies are
done, do they control for spontaneous abortion or
not, or do you know?
Mr. Liu: Some do and some don’t. And part of
the problem in some of these studies is that many
times the larger the studies, the more difficult it
is to discern the mode of the abortion. But I think that the therapeutic
abortion piece has been looked at, as Dr. Coburn has
addressed. In terms of the biology, I will have to
defer to reproductive biologists, my colleagues, to
give the exact answer, but there is some truth to what Dr. Coburn
has mentioned in that there are many ways to get a spontaneous abortion.
Usually it is, an unfortunate term, called fetal wastage and inadequate
fetal production, in which case many of the hormonal pieces are not
in order. Now, it is highly varied, though, and it is difficult to determine,
and there may be differences in terms of timing of these abortions.
But I think that it is best for me to defer these questions
and answers to somebody a little more adept at the
data. My colleague Dr. Joe Fraumeni is responsible
for the intramural program for epidemiology and would be best to
answer these questions.
Mr. Green: Yes. I don’t have any questions for
our panel. I have a question for our physicians on
the other side. In all seriousness, I think the
question that Dr. Coburn has brought up, maybe our committee or our
subcommittee should schedule a work session so we do not
take any more time from Dr. Liu, so a lot of us
could learn more that are not physicians about NIH.
Mr. Whitfield: Right. We can pursue that, and Dr.
Coburn is going to have additional questions, and
you will get back for the record on that. So thank
you very much for staying over.
Now, the piece that you have talked about, the many studies, having done
epidemiologic studies, and you may have done yourself, is
that one study doesn’t make a conclusion, and
there are many problems with smaller epidemiologic
studies.
Mr. Coburn: I agree.
Mr. Liu: In particular, this is true in the
United States where reporting biases are quite
dramatic for a variety of reasons, social and otherwise.
This type of bias clearly changes the outcome that is an artifact of
the study and has no basis in reality. For this reason, many of the later
so-called confirmatory studies had to go to data bases
outside of the United States where the biases are
not so intense, and it is from those studies as well
as studies with meta-analyses that came to the conclusion that there is
no clear association between abortion and breast cancer
risk.
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