Evidence of meeting #94 for Health in the 44th Parliament, 1st Session. (The original version is on Parliament’s site, as are the minutes.) The winning word was risk.

A video is available from Parliament.

On the agenda

MPs speaking

Also speaking

Heather Jeffrey  President, Public Health Agency of Canada
Donald Sheppard  Vice-President, Infectious Diseases and Vaccination Programs Branch, Public Health Agency of Canada
Steven Narod  Senior Scientist, As an Individual
Jacques Simard  Full Professor, Department of Molecular Medicine, Université Laval, As an Individual
Anna Wilkinson  Doctor of Medicine, As an Individual
Paula Gordon  Doctor, Dense Breasts Canada
Jennie Dale  Co-founder and Executive Director, Dense Breasts Canada

December 6th, 2023 / 8:50 p.m.

Conservative

Robert Gordon Kitchen Conservative Souris—Moose Mountain, SK

Thank you, Mr. Chair.

I want to thank all of you for being here, and the people in the audience as well. I commend them for being here.

Part of my discussion and my concern is that there are people watching. There are women watching this conversation, and they are concerned. They are very concerned about what's going on, about themselves and about the future for women in this country. It's great to hear many different aspects of this. I recognize the challenges we've had. I've been all over the map with questions I want to ask.

Ultimately, I recognize the challenges we have in doing RCTs in this subject area and the potential that could be there in someone designing that. Dr. Wilkinson, your comments about working with patients, I think, are tremendous, and dealing with women and understanding that.

In my years of practice.... I'm from a rural part of Canada, where I had many women come to me with signs and symptoms that were outside my scope of practice. They came to me because they realized that I would at least refer them to where I felt it was appropriate, to at least be assessed. My home is 14 miles from North Dakota. In North Dakota, they basically have 18-wheelers with mammography units, and they travel all over the state to do testing.

When I see recommendations from the U.S., where they recommend biannual testing for women between 40 and 74, I see that as a concern as to the research and the science they would have used to get that.

Dr. Wilkinson, what are your thoughts on that? If they had some research to support that, why don't we?

8:50 p.m.

Doctor of Medicine, As an Individual

Dr. Anna Wilkinson

That's a very good question. That's the crux of the matter, I think. We need to move beyond the old data. We need to move beyond 60-year-old data. We cannot use data from before we landed on the moon to determine our breast cancer guidelines now. We are moving into uncharted territory.

I'm not a methodologist. I'm not a guideline expert. I'm not going to pretend I know how to do this, but I do think we need to think about different methodologies and to involve different kinds of data. Right now, although different data is involved, if it's an RCT, even if it's a really old, crappy RCT, it still trumps a non-randomized study. Those numbers from those randomized studies are still driving.

We need to look at what the U.S. is doing. I think we need to use modelling data. There's a new paper just out that shows screening women in their forties saves 3.3 deaths per thousand women screened. Move to modelling and use a lot of the epidemiological data, because our society is changing, the incidence is changing and the ethnic makeup of our society is changing. We have to do more of a holistic investigation to do that.

8:50 p.m.

Conservative

Robert Gordon Kitchen Conservative Souris—Moose Mountain, SK

Thank you. I appreciate that.

When we hear about guidelines that are basically suggesting they are against self-screening, that's a concern to me, especially in rural areas—not just rural but urban as well—where there are concerns that you can't access a practitioner to even get that done. At least the self-screening would provide some form of understanding. I think that's information women need to understand. They need to be prepared to learn how to do it and do it, so that they at least understand when they need to see that practitioner.

On that note, the concern I have, having been a regulator in the profession and having dealt with things, is that there is a difference between guidelines and standards. When we talk about guidelines that are presented, where practitioners see those guidelines, they don't necessarily look at it the same way as they might look at standards. I'm just wondering about comments you might have that maybe these things should go even further than guidelines and become standards.

8:50 p.m.

Doctor of Medicine, As an Individual

Dr. Anna Wilkinson

Guidelines would be a really good start. We need something. We have an opportunity, and I think the national guidelines are a federal issue, because they are impacting all the outcomes in the province. We have an opportunity to do this differently, to be creative and to think about the impact of what we're doing.

For example, in the U.S., when they recommended against prostate screening, or PSA screening, they looked at their mortality rates, found they were going up and reinstituted it. Whereas, we made that recommendation 10 years ago, and I don't think we have ever looked back at that. It's not a women's health issue, but it's an example of the broader reach. Although standards would be lovely, I think we need to start first with really grounded guidelines. We really need to have regular updates of guidelines, given the quick pace of medical literature change these days.

8:55 p.m.

Liberal

The Chair Liberal Sean Casey

Thank you, Dr. Wilkinson.

Next, we have Dr. Powlowski, please, for five minutes.

8:55 p.m.

Liberal

Marcus Powlowski Liberal Thunder Bay—Rainy River, ON

I hate to bring this up and get into this controversy, but Dr. Gordon, I think you suggested that the current task force recommendations on screening were largely based on Dr. Narod's randomized control trial, which I think you've said is flawed.

As I recall, having discussed this with you before, the basis of the flaw was the improper randomization, in that at least some of the nurse practitioners who were involved and doing the randomizing, when they felt a lump in the screening exam, put them in the mammography group. Therefore, yes, at the end, you are going to have more deaths in that group because you have a lot of people in that group who are in there because they had cancer to begin with. That gave a skewed outcome.

Am I right in that this is what you're saying? What evidence do you have that it is, in fact, what happened?

8:55 p.m.

Doctor, Dense Breasts Canada

Dr. Paula Gordon

That is what we're saying. In fact, there were 28 former staff who came forward with evidence of protocol deviations. That's what they're called. That wasn't the only problem with the Canadian trial. In fact, they allowed women to be participants even if they had a known breast lump. Screening is for women with no lumps.

First of all, they allowed these women to participate. They were having trouble recruiting enough women for the study, and they actually approached breast surgeons to send patients to be in the study. The reason a woman goes to a breast surgeon is that she has a lump or a symptom.

First of all, they allowed these women to participate. What was supposed to happen was that every woman who came to participate—they were volunteers—got a clinical breast exam by a highly trained nurse, and then they would go to the coordinator, who would decide to put her in either the study group, where they got a mammogram, or the control group, where they didn't.

Nowadays, when we do these studies, the randomization is done by a central office, by a computer. In those days, the coordinators had a piece of paper in front of them with lines. The lines would say, “mammogram, control, mammogram, mammogram, mammogram, control, control”, and at the end of the sheet, you'd have an equal number of women in both arms.

What we know happened, because witnesses came forward and told us—and these are in three peer-reviewed published papers, by the way—is that the nurses would say, “This lady has to be in the mammogram group,” so the coordinator could write her name on the next available mammogram line, and then other women who came in later in the day could go in any blank lines that she had left. They didn't even have to make any erasures.

This was actually picked up in 1992, which was the first publication of the Canadian national breast screening study, because there was a significant imbalance of advanced cancers. In the very first year of the study, there were 25 advanced cancers, which they defined as a cancer with more positive lymph nodes in the armpit. There were 19 of them in the mammogram group and only five in the control group.

This was raised decades ago, and the principal investigators at the trial have denied it to this day. They claim that there was nothing wrong with the randomization. There was even a forensic—

8:55 p.m.

Liberal

Marcus Powlowski Liberal Thunder Bay—Rainy River, ON

Dr. Gordon, I'm sorry. Can I cut you off?

In fairness, I want to give Dr. Narod an opportunity to respond to this.

8:55 p.m.

Senior Scientist, As an Individual

Dr. Steven Narod

You give my study.... You gave all the time for your question to Dr. Gordon, who.... I have 30 seconds now.

Okay. Let me—

9 p.m.

Liberal

Marcus Powlowski Liberal Thunder Bay—Rainy River, ON

I'm giving you time, and other people can give you time as well, but I want to hear from you in response to that accusation.

9 p.m.

Senior Scientist, As an Individual

Dr. Steven Narod

This is my study. The data is on my computer.

Dr. Gordon and others made a claim of scientific misconduct at the University of Toronto last year, at which point I prepared a report on exactly what she's claiming. That report was submitted to the dean of public health sciences and was submitted to an international committee that reviewed the study and came out entirely on my side.

Let me tell you a couple facts. In the first round of screening, there were 270 palpable cancers on the mammography side, and 274 palpable cancers in the control group. If we had shunted women to the mammogram group who had a palpable cancer, that number would be different. There were 270 in the mammogram group, and 274 in the non-mammogram group.

Second, I removed all those women from the first round. I removed all the women with a palpable cancer from the analysis and reran it. The hazard ratio is 1.01.

Third, if what they are saying is true, then death from the cancer excessive in the mammogram group should have occurred in the first five years. This is a 30-year study. When I looked at the annual rates of mortality in the 30 years of follow-up, there was no difference in year one, year two, year three, year four and year five.

What Dr. Gordon is alleging is that I should see an excess of breast cancer deaths from the people who had prevalent breast cancer in the first round of screening, at which point we should see a high rate in the first group.

If I remove all the palpable cancers, which you can do, then I can get a hazard ratio of one. Second, the concept of a palpable cancer being excluded is ridiculous. Let's put it this way. In the studies that Dr. Gordon claims are the ones that provide evidence in favour of mammography was a Swedish two-county study. That was a study where the randomization was in 16 blocks of counties in Gothenburg and Östergötland, Sweden.

What did they do? The invited half the women to have a mammogram, and they didn't invite the others. They were just followed. Following the cancer rates—

9 p.m.

Liberal

The Chair Liberal Sean Casey

Dr. Narod, Dr. Ellis may elect to have you continue, but we're over time.

Dr. Ellis has the floor next for five minutes.

9 p.m.

Conservative

Stephen Ellis Conservative Cumberland—Colchester, NS

Thanks very much, Chair.

Obviously there are some significant feelings on both sides of this argument that we are experiencing.

Dr. Narod, maybe you could sum up. I think it's only fair to allow you to have your say. You've been at this a long time.

9 p.m.

Senior Scientist, As an Individual

Dr. Steven Narod

Thank you.

In the Swedish trial, they invited women to come for a mammogram, and half the women were not invited.

How do you know that they didn't have a palpable cancer? The ones who came they could have excluded with a palpable cancer, but the controls were never examined. They don't know if they had a palpable cancer or no cancer. That trial, the Swedish trial, is considered the gold standard. I have reviewed it very closely and found many things that I consider to be inadequate.

Dr. Gordon claims that there are eight trials, of which only the Canadian trial is an outlier. I would love to see the other seven. The only two I know of are the Swedish trials. I would love to see the references to the other six trials that I'm not aware of. I'm only aware of the U.K. age trial, which showed no effect.

I'm aware of the HIP trial, which showed no effect after 15 years of follow-up, and the Edinburgh trial.

To come to this committee and say that there are eight trials that show an effect for randomized trials and one that doesn't is something that.... If I were on this committee, I wouldn't wish to have that evidence.

Trust me—it's not there. There are not eight trials that show a benefit. If there are, I'll be very willing to apologize to Dr. Gordon and the others.

9 p.m.

Conservative

Stephen Ellis Conservative Cumberland—Colchester, NS

Thanks, Dr. Narod.

9 p.m.

Doctor, Dense Breasts Canada

Dr. Paula Gordon

I'm happy to supply that evidence later. We'll supply that evidence.

9 p.m.

Senior Scientist, As an Individual

Dr. Steven Narod

Yes, I'd love that.

9 p.m.

Conservative

Stephen Ellis Conservative Cumberland—Colchester, NS

Dr. Gordon, if you could table that with the committee, we'd be ever so grateful.

Dr. Simard, you haven't had a chance to weigh in.

If I might summarize, I think we've heard that Dr. Wilkinson and Dr. Gordon would suggest that moving the age for screening for asymptomatic women to age 40 would be appropriate and supported by the science. Dr. Narod, I would suggest, is not supportive of that change. Again, I'm not one to put words in people's mouths.

Dr. Simard, I know your focus is slightly different and is—if I could use a term—talking more about precision diagnostics. I think that's obviously the way of the future.

If you have an opinion, sir, could weigh in on what you think the Canadian task force should be doing? I think that would be beneficial.

9:05 p.m.

Full Professor, Department of Molecular Medicine, Université Laval, As an Individual

Jacques Simard

What we proposed is to have a risk assessment, for example, at 40 years old. Based on their risk category—it's a risk stratification—those women who have a risk equivalent to the population can start later. However, the 20% of women having an intermediate or high risk should start at 40 years old. I think it's important to have a comprehensive risk assessment.

By the way, it's not so futuristic. We need the political will. We released the comprehensive risk prediction tool—by my colleague at the University of Cambridge in the U.K. Since 2020, already it has been used 1.7 million times in 120 countries.

This is the real world. Of course, if it's not currently available, the polygenic risk score, it will cost the same amount of money as a mammogram—around $100. It can be done once in a lifetime. It just needs political will to introduce this test. Any good genomic lab in Canada—because we have a very good platform and we have clinical labs—can perform maybe 5,000 to 10,000 tests per week. It's not so futuristic. We need political will to introduce innovation. The goal of our research is to provide innovation.

Two weeks ago, the Ministry of Health, during the annual meeting of the Quebec cancer program, gave us the award for our project for health promotion and prevention of cancer.

9:05 p.m.

Conservative

Stephen Ellis Conservative Cumberland—Colchester, NS

I'm sorry. Dr. Simard, can I just interrupt you for one second?

When we're talking about the Canadian guidelines, would you suggest, then, that there would be an addition to say that the polygenic screening that you have researched should be a part of those guidelines as well?

9:05 p.m.

Full Professor, Department of Molecular Medicine, Université Laval, As an Individual

Jacques Simard

A comprehensive risk assessment...yes.

9:05 p.m.

Conservative

Stephen Ellis Conservative Cumberland—Colchester, NS

Can you table that research with the committee, Dr. Simard?

9:05 p.m.

Full Professor, Department of Molecular Medicine, Université Laval, As an Individual

Jacques Simard

I provided a slide deck. They should provide you.... They are just looking for the translation, I think.

9:05 p.m.

Conservative

Stephen Ellis Conservative Cumberland—Colchester, NS

That's perfect. Thank you, sir.

9:05 p.m.

Liberal

The Chair Liberal Sean Casey

Thank you, Dr. Simard.

Thank you, Dr. Ellis.

Next we have Mr. Jowhari, please, for five minutes.