THE STATE OF CANCER RESEARCH
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
JULY 20, 1998
(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.