Health Committee on June 13th, 2024

[Dr. Martin Yaffe]

Thank you.

It is important for us to understand the causes of cancer and to continue to look for the means to prevent cancer. We know there are some issues around alcohol consumption. There are lifestyle issues, such as obesity. However, at the same time, prevention and early detection and treatment are not competing with each other. While we're learning how to prevent cancer, we should be doing what we can to prevent women from dying of breast cancer.

Screening is often referred to as secondary prevention. We're preventing advanced disease. If we find it earlier, it's treated much more successfully. It's better for the patient. It's also better for the health care system. Research that's about to be published shows that costs go down as you do more screening, because you have fewer advanced-stage cancers that need to be treated.

[Luc Thériault, Bloc, Montcalm, QC]

Thank you very much.

[The Chair, Liberal, Sean Casey]

You still have two minutes, if you like.

[Luc Thériault, Bloc, Montcalm, QC]

I thought I had two and a half minutes.

I am happy to keep going.

[The Chair, Liberal, Sean Casey]

No, you had six minutes.

[Luc Thériault, Bloc, Montcalm, QC]

Okay, thank you.

Many experts are critical of “false positives” during screenings and support this phenomenon to not recommend systematic prevention in women 40 to 49.

What do you think? Can you provide more details on this?

[Dr. Martin Yaffe]

I'm sorry. I missed the first part of your question. I thought I heard “false positive”. Is that what you're talking about?

[Luc Thériault, Bloc, Montcalm, QC]

Yes, many experts are critical about the adverse effects of false positives.

I am listening.

[Dr. Martin Yaffe]

First of all, we need to get away from the term “false positive”. It's completely a misnomer. A false positive implies that someone has said somebody has cancer when they don't. What the term really refers to, as I think Dr. Kulkarni mentioned earlier, is when women are asked to come back for additional imaging to make sure there's no cancer. The first screening exam is not absolutely clearly negative, and they want to make sure they don't miss a cancer.

If it takes a while before the answer to that additional imaging comes out, there will be some anxiety, but much of the research shows that the anxiety is transient. As Dr. Seely mentioned, patients are generally much happier to accept that anxiety as opposed to the chance of a missed diagnosis of cancer and the need to treat advanced disease. The task force is really off base in considering that as a harm. We should try to reduce anxiety, not reduce the detection of cancer.

[Luc Thériault, Bloc, Montcalm, QC]

Thank you.

According to the working group that made the recommendations, the risks of excessive screening would far outweigh the benefits. Increased anxiety, unnecessary tests and overdiagnosis such as biopsies are apparently some of the inconveniences caused.

Do you think that the overdiagnosis referred to in the studies that were used is generally overblown?

[Dr. Martin Yaffe]

I co-authored with medical oncologist Dr. Kathleen Pritchard, one of Canada's outstanding medical oncologists in breast cancer, a paper called “Overdiagnosing Overdiagnosis”. The point is that some cancers will grow slowly. For some people, if they didn't know they had cancer, that cancer may not have bothered them before they died of some other cause. The reality is that the fraction of those cancers—these are real cancers, but they're cancers that perhaps grow slowly—is relatively small. It's generally under 10%, and perhaps is in the order of 5%.

The idea is to avoid overtreating those individuals. Once a cancer is diagnosed, try to determine if it's going to be one of the aggressive ones or the less aggressive ones and make therapy suitable for the characteristics of the cancer. I think that's the right approach, rather than not finding the cancer and playing Russian roulette with letting a dangerous cancer continue to grow.

[The Chair, Liberal, Sean Casey]

Thank you, Dr. Yaffe.

[Dr. Supriya Kulkarni]

May I add to that?

[The Chair, Liberal, Sean Casey]

Be very brief, please.

[Dr. Supriya Kulkarni]

I want to echo Martin's sentiments that overdiagnosis is a word that is very difficult to understand. The role of screening is to find the cancer. How to treat the cancer is a different aspect of the cancer. To determine which cancer will be biologically aggressive and will grow and kill the woman versus which cancer will not grow but will allow the woman to die of some other cause.... That's something we cannot tell based on imaging.

It's not really overdiagnosis. We have to figure out which cancer needs treatment and which doesn't. That's not part of the screening process.

[The Chair, Liberal, Sean Casey]

Thank you.

Next is Ms. Zarrillo, please, for six minutes.

[Bonita Zarrillo, NDP, Port Moody—Coquitlam, BC]

Thank you.

I really appreciate the comments by Dr. Kulkarni because in modernized cancer treatments, there are many more options.

It was a year ago exactly that Minister Duclos announced up to $500,000 in additional funding for the task force to help expedite the update of the breast cancer screening guidelines. He's quoted as saying, “having breast cancer screening guidelines that are based on the latest science is essential.”

Dr. Yaffe, I wonder if you think this task force's new guidelines are based on the latest science.

[Dr. Martin Yaffe]

I think they would say they have looked at the latest science—at least some of the latest science—but because they have continued to focus so much on these 40- to 60-year-old studies, that raises concerns.

The more modern data shows mortality reductions in the range of 40% to perhaps even as high as 60% for women who participate in screening—emphasis on the word “participate”—and that the stage at which the cancer is found is earlier, which means it can be treated more successfully with better outcomes, less morbidity and at lower cost. I don't see that in anything the task force has put in its literature. I've read its reports. There's nothing that clarifies that it has taken the more modern data seriously.

As mentioned earlier today, there's nothing on breast density. There's nothing on women who are racialized, whose breast cancers tend to occur earlier and be more aggressive in some cases and whose outcomes, we know, are worse. They do much worse. There's an inequity there.

[Bonita Zarrillo, NDP, Port Moody—Coquitlam, BC]

Thank you, Doctor. That inequity is something I'm really concerned about. I want to ask a question about that later.

I just want to follow up on one thing, Dr. Yaffe. Do you have any information on the parameters that the government gave this task force? Specifically, is there a cost-saving requirement? Was there an ROI that this task force was asked to do in relation to women's health and breast cancer?

[Dr. Martin Yaffe]

I don't know the answer to that question. I suspect there is an underlying sentiment among task force members that spending less money on breast cancer screening will free up money to do things they may be more interested in, but I don't know that for a fact. As I mentioned, what we've learned is there's a potential cost reduction associated with screening.

[Bonita Zarrillo, NDP, Port Moody—Coquitlam, BC]

I'm going to ask Dr. Kulkarni the same question. Do you have any information on the parameters the government gave the task force and anything that might be related to that?

[Dr. Supriya Kulkarni]

No, I don't think this information is available to any of us from the outside. I don't have any information.

I'll just address another thing that was brought up, which is that mammographies don't pay that well. It is a misconception that reading more mammograms is an easy job. For example, a mammography would pay 10 times less than what a CT scan would pay. Anything related to women's health is not that well reimbursed, so you can see there's another problem there. It's not being prioritized.

No, there's no information.

[Bonita Zarrillo, NDP, Port Moody—Coquitlam, BC]

I appreciate that. The work of women is not compensated properly in the medical industry.

Dr. Kulkarni, what expertise do you believe needs to be included in the task force with the back-to-the-drawing-board recommendation that could come from this committee?

[Dr. Supriya Kulkarni]

They invited some advisers—we heard from two of them today—for the evidence review. Other advisers were working directly with the task force. All of these people need to be talked with.

Find out if the decisions that were made—the draft recommendations—were a unanimous decision. Were there any people within the team who felt this was not okay to do? That's one thing.

The second thing, as we saw, is that these recommendations cannot go forward as they are. They need to be reversed or they need to be at least temporarily stopped until the investigation is fully over. All family physicians should be encouraged to follow provincial guidelines for the time being until this is resolved. Rolling them out the way they are will be detrimental to the country.

[Bonita Zarrillo, NDP, Port Moody—Coquitlam, BC]

With that, Mr. Chair, I would like this committee to ask the Public Health Agency of Canada and the government to supply to this committee the parameters that were given to the task force for their updated study.

I have another question, Dr. Kulkarni. Dr. Yaffe noted the debate with the doctor. That was certainly my experience as a woman with dense breasts. I had to have a debate with my doctor for two years. I worry about non-white people. Dr. Seely mentioned earlier how much they have to debate and fight against prejudice and bias.

I'm wondering, if you wouldn't mind sharing, how we overcome bias at the doctor's office.