Understanding Your Breast Cancer Risk

[00:00:00] Adam Walker: From Susan G. Komen, this is Real Pink, a podcast exploring real stories, struggles, and triumphs related to breast cancer. We’re taking the conversation from the doctor’s office to your living room.

Whether you’re concerned about your risk of breast cancer, have a history of breast cancer or other cancers in your family, or are curious about genetic testing, the first step is learning more about risk.  Everyone is at risk of breast cancer, and some of us are at a higher risk than others.  We are pleased to have Dr. Anne Marie McCarthy, an assistant professor of epidemiology from the University of Pennsylvania School of Medicine here today to help educate us about breast cancer risk so we can feel empowered to make important breast care decisions and take charge of our health. Dr. McCarthy’s research is focused on developing ways to identify women who are at a high risk for aggressive breast cancer.  Dr. McCarthy, welcome to the show!

[00:01:02] Dr. Anne Marie McCarthy: Hi, Adam. So nice to be here. Thanks so much for having me.

[00:01:04] Adam Walker: I love getting to interview researchers such as yourself and get your perspective. It’s the work you’re doing so important, and I feel like your perspective is so important. So let’s start with a broad perspective of risk. How does someone determine their risk for developing breast cancer, and what are some of the factors that contribute to an increased risk for developing breast cancer?

[00:01:26] Dr. Anne Marie McCarthy: Great. Yeah. So as you mentioned in the intro, anyone with breasts is at risk for breast cancer. However, breast cancer is the most commonly diagnosed breast ca cancer in women in the us.

Breast cancer can occur in men as well, though it’s much less common. Okay. And so, even though breast cancer can happen to anyone, we do know a lot about risk factors that might increase your risk relative to other people. And so one of the ones that we think about most often, or one of the kind of obvious risk factors for breast cancer is family history.

So if you have women in your family who have been diagnosed with breast cancer, or if you have men in your family who have been diagnosed with breast cancer, then your risk of developing breast cancer in your lifetime is higher. And we can talk a little bit more about genetic testing. I think we’ll talk about that in a minute.

But that is a strong risk factor for breast cancer. Another obvious risk factor that a lot of people forget is age. Breast cancer can occur in young women. However, it’s much more common in older women. So age is one of the strongest risk factors for breast cancer. And we need to focus on making sure older women are screening for breast cancer to the same extent that younger women are.

We also know that reproductive factors are associated with breast cancer risk. The hypothesis is that the lifetime exposure to hormones such as estrogens can impact your risk of developing breast cancer. And so, for example, for women who get their period earlier in life that is associated with higher risk of breast cancer, women who go through menopause later have a higher risk of breast cancer because it’s longer period of time, more years where you’re exposed to ovarian hormones. Number of pregnancies in age at pregnancy can impact breast cancer risks. So women who have more children and have children earlier in life tend to have a lower risk of breast cancer than women who don’t have any children.

And also breastfeeding can influence breast cancer risk as well being protective against developing breast cancer. And then in a addition to reproductive factors in your medical history. So if you’ve had breast cancer before, you’re at higher risk for developing breast cancer. Again. If you’ve had DCIS ductal carcinoma insitu or stage zero breast cancer, you’re at increased risk of developing an invasive breast cancer.

And if you have had a prior breast biopsy, and if. Had diagnosis of atypical hyperplasia or LCIS on your breast biopsy, then your risk is higher as well. So knowing about, you know, and communicating what’s happened in your past medical history is very important for understanding breast cancer risk.

Couple other breast cancer risk factors. One I’ll talk about later when I talk about my research is breast density. So breast density is a strong risk factor for breast cancer. And then there’s some, a lot of the factors I’ve talked about aren’t really things we can do anything about particularly if we’re past childbearing age.

But there are modifiable risk factors that we know influence risk of cancer. So things like healthy. Exercise, obesity smoking, those are all things that have been associated with breast cancer risk that we can control. So, in general you know, having healthy eating habits, getting exercise trying to maintain a healthy weight all of those things are going to be beneficial for your health across the board, but also for breast cancer risk.

[00:05:09] Adam Walker: Wow. That, I mean, that was really helpful because I’ve talked to a. Professionals on this show. And we’ve talked about risk many times, but you mentioned several that I had never thought about or heard about, and so I, I mean, especially like women that have had more children versus less children and things like that was incredibly insightful and helpful.

I, I really appreciate you sharing that. So, so what are the recommended next steps for someone if they have any concerns about their breast cancer risk?

[00:05:37] Dr. Anne Marie McCarthy: Yeah. So I think kind of the first step is always to be informed and to learn, which everyone who’s listening to this podcast is already a big step ahead because they’re learning about their health.

And so the Komen Foundation has a really fantastic website with lots of great information about you know, risk factors for breast cancer and things that you can ways that you can learn more. I would encourage people to stick to, you know, websites that. That are evidence-based, such as the Komen Foundation.

And then once, once you’ve gone that far I think it’s always a good first step to talk to your primary care provider. And so, Primary care providers are really busy, and many people only see their primary care provider when they’re sick. But if you’re kind of looking at this list of breast cancer risk factors and thinking, oh I have a lot of these, or I, somebody in my family just got diagnosed with breast cancer, what does that mean for me?

I would encourage scheduling a well visit with your primary care provider where you can go and talk. Your prevention steps for breast cancer and other cancers as well. It’s always a good idea to go to the doctor and make sure you’re you’re doing your prevention in addition to, you know, typically people, some people don’t think to go to the doctor until they’re actually sick.

And so. When you talk to your primary care provider, they can help you think through you know, how, based on your age and all of these other factors, should you think about screening. Now, should you think about screening earlier than, you know, average women, should you hold off on screening? What type of screening should you think about?

If you have a family history, should you consider genetic testing? If you do have a family history, Worried or interested in learning more about genetic testing? Genetic counseling is a really good step. So that’s kind of a step before you actually get the genetic test. You go to the genetic counselors and they’re experts in genetic risk for cancer.

They can take a look at your family history and they can make recommendations as to whether they think you should have genetic testing or not. There’s also some genetic counseling that’s available online now through virtual visits. So, there’s a lot of there, there’s expanding resources for genetic testing.

[00:07:54] Adam Walker: Well, and I know your research includes understanding a person’s gen genetics and how that contributes to breast cancer. So, like how does all that factor into like genetics and testing factor into breast cancer risk? And how would a listener like take next steps if they want to consider genetic testing?

[00:08:11] Dr. Anne Marie McCarthy: Yeah. So right now we know several mutations that increase breast risk for breast cancer quite substantially. So most people have, many people have heard of B RCA one and b RCA A two. Those increase your risk of both breast and ovarian cancer drastically. So a woman’s average lifetime risk of breast cancer around one in eight.

Around 12% ish. A woman with with a BRCA one and two mutation, their lifetime risk of breast cancer is 60, 70, 80%. Hmm. So very drastically increases risk. There’s some other what we call high penetrance or strong breast cancer genes like PAL b2 P 53. T 10 that also increase your risk of breast cancer, but maybe not so high as as, as as BRC one or two.

So for those mutations women are when, and men are recommended to take extra steps to prevent. Breast cancer. So some of those steps might be more frequent screening, screening with breast MRI, in addition to mammography. Some women with B R C mutations may choose to have their breasts or ovaries removed to reduce their risk.

And you can take drugs such as tamoxifen, which can reduce risk. So having the information about a mutation, it doesn’t, it can cause obviously, it can cause Worry and anxiety if you’re diagnosed with a mutation, but it also gives you this information that can help you take more drastic steps to reduce your risk.

Now, ok. Who should think about genetic testing? So, Typically right now we’re focusing on patients who have some family history of breast cancer. So right now we’re not recommending that everybody go out and get testing for breast cancer genes. And the reason we’re not doing that now is because these genes are very rare in the population.

So, for example, For the BRCA genes, it’s maybe one in 400 or so, have a BRCA mutation. So, we’re not right now. Recommending everyone go out and get genetic testing. However, that might change in the future. So stay tuned. As the costs of breast cancer genetic testing come down there’s more and more debate like maybe we should just test everybody, but we’re not there yet.

So right now you should find out about your. Your family history of breast cancer. And that seems easy, but that’s really not easy for everyone. Not everyone has relationships with all their family members. Not every family communicates about you know, cancer breast, particularly if it happened a long time ago, you might know, oh, that person died of cancer.

Well, what? Cancer? I don’t know. So that can happen. But it is also, another thing I’d like to point out is that The genetic factors for breast cancer can be passed on the maternal or the paternal side. So if your mom’s side of the family has breast cancer, that’s important for your risk and it’s just as important if your dad’s side of the family has breast cancer.

So, think about that. And if you have one or more close family members with breast cancer, you should talk to your primary care doctor and ask them to refer you for genetic counseling so that you can determine whether. Genetic testing might be right for you. And they can also help you with determining if you, if your insurance will cover genetic testing.

Insurance insurers do cover genetic testing, but they have different requirements for who they cover it for. .

[00:11:54] Adam Walker: Yeah. Yeah. That’s great. That’s great advice. So, can you tell us about the focus of your research and specifically how high risk women can be identified in the

[00:12:04] Dr. Anne Marie McCarthy: clinic? Yeah, so, so I’m really interested in changing the way we do mammography screening and breast cancer screening as a whole.

So right now we make our recommendations mostly based on age. So we say, if you’re this old, you should consider mammography, or if you’re this old, you should wait. We say that, you know, depends on who you’re talking with. What like, which organization? Some say every year, some say every other year.

So we’re mainly using age, maybe family history is in there as well. But we’re really not using all of the information we have about breast cancer risk factors. Make decisions and make recommendations about who should be screened. And so a lot of my work is trying to figure out if we can get better at predicting who is going to get breast cancer so that we can really target screening and prevention strategies to those women.

And so that’s really where we’re at and. Right now we’re not honestly very good at predicting which women are gonna get breast cancer or not. So we talked about family history, which is a very important and strong risk factor for breast cancer, but most women who get breast cancer don’t have a family history.

Right. So it kind of cuts both ways. And so I’m interested in using new risk factors to do a better job of picking out the women who are most need of screening and. . And so I’m using two main risk factors. So I’m looking at genetic factors and I’m looking at breast density, which I mentioned before, but I’ll talk about in a little bit more detail.

So breast density is the amount of dense versus fat tissue in a breast. So, women who have a lot of dense tissue in their breast, it shows up as white on a mammogram, whereas the fat and skin is dark on the mammogram. Cancers look white too on a mammogram. So if you have very dense breasts, the dense tissue can kind of block out tumors and it makes it harder for the radiologist to detect a cancer that’s there.

So women who have highly dense breasts, they’re more likely to get breast cancer, and they’re also more likely to have a cancer missed on a mamo. So mammography is great. It’s very effective at reducing breast cancer mortality, but like all tests, it’s not perfect. And there are some false negatives.

I think we’re all a little bit more attuned to what a false negative is with covid testing now. So, you know, some people, they’re coughing, they had a fever, they take the test. It comes back negative. It’s the same thing with mammograms on a v in a very small number of cases. The ma the mammogram might not detect the breast cancer.

And so my work is, I’m working with a computer scientist here at the University of Pennsylvania named Despina Contos, and her lab is developing imaging biomarkers. So her lab is, Has computer scientists and they take the mammogram image and they run computer algorithms, use some ai to pick out which women might be at higher risk for breast cancer.

And then we could use that perspectively when women come in for a mammogram, we could apply the computer technology and say, oh, this looks. There might be something going on in this woman’s breast, or this looks like a person who has a high propensity to detect breast cancer. And we’re hoping that these newer kind of imaging biomarkers might help us pick out risk beyond what we’re able to do now.

And so we have a lot of exciting studies we’re working on together in that realm with breast density. While I’m talking about breast density, I should mention that the typical way that breast density is measured is the radiologist when they look at their mammogram, Determine how dense your breasts are, and they rate breast density on a four level scale.

And so women with the top two categories of breast density have higher risk of developing breast cancer. And There’s been some trials showing that for women with particularly the highest category of breast density, extremely dense breasts, if those women get breast MRI, it might improve their breast cancer detection and reduce the number of missed cancers.

And so there’s been a lot going on across the US in terms of breast density and notifying women about their breast density and. Enabling women to determine whether breast MRI makes sense for them. Mm-hmm. . And some states are also legislating for insurance coverage of supplemental breast cancer screening with ultrasound or mri.

So you should depending on what state you live in, and if you have extremely dense breasts, you might be able to qualify for breast MRI in addition to mammography. And it is more sensitive, although it’s more expensive, it takes more time. You have to get an iv and. The false positive risk is higher.

So we’re really right now only recommending MRI for women at high risk and women with extremely dense breasts. But again, this is an active area of research. I’m working with Emily Conan here, who’s a breast radiologist, and looking at breast MRI screening and how that could be used to do a better job of at detecting breast cancer.

[00:17:21] Adam Walker: Well, so you unpacked several things that I’ve wondered about many times on this show and that. Really just profoundly helpful. Like I never understood before why breast density was a problem for mammograms. And so like you, you explained that, which was really helpful. And then I, it also occurs to me that it would probably be good for women to be aware, at least peripherally of what their breast density is.

It not only how that pertains to their risk, but then how that pertains to what tests they need to have to mitigate that risk. Right. And

[00:17:52] Dr. Anne Marie McCarthy: now it’s mandated nationally that mm-hmm. , it needs to, breast density level needs to be put in mammogram reports. Oh, wow. Okay. So it’s great going out there. Many in many places.

That’s really all as far as it goes, as it gets put in the mammogram report and maybe Right. It’s looked at, maybe it’s not, but that’s definitely something you can inquire about. When you get a mammogram, you can look at your breast density level and ask, you know, would you ask your provider? Would you recommend breast mri?

You can Google in your state to see what the insurance coverage laws are. I know in my state of Pennsylvania, there was a law passed about a year and a half ago mandating supplemental screening for women with extremely dense breasts. So, It’s depending on where you live, you might be able to qualify it.

And then that’s just looking at breast density. When you add together breast density and some other risk factors, then that might be able to qualify you to get supplemental screening. So that’s an, you know, breast MRI is emerging as a potential tool. It’s not a tool that’s gonna be worthwhile for everyone. So I just, you know, be aware of it, talk to your provider and see whether it makes sense.

[00:18:56] Adam Walker: So then what, so what does the future hold for breast cancer screening and where do you think improvements are gonna be made in the near future and in maybe in the distant future?

[00:19:06] Dr. Anne Marie McCarthy: Yeah, I mean, I think we’re gonna get a, we’re gonna get a lot better at being able to tell women who needs what and when do they need it, and how often do they need it.

And I think we are gonna be able to bring in actual evidence to do that. I think we’re gonna be able to do this personalized approach and I’m really hopeful with the work that we’re doing, we’ll be able make a contribution there. So I talked about, I talked a bit about MRI screening in terms of the genetics I’ve talked a lot about the high.

Mutations. But there’s another aspect of genetics that we’re learning more about called polygenic Risk Score. And so I talked about the really high risk mutations, so BRCA one and two. They’re very rare mutations, but they increased your risk by a lot. There’s also a lot of other common genetic variants and each one on their own might only increase risk or decrease risk of very small percent, maybe 3%, 5%, 15%.

So like the. Particular polymorphism isn’t changing your genetic risk that much, but what we’ve seen is if we pull across the genome, all of the variants that are associated with breast cancer and kind of pull them together, make a summary score when we put it all together, it actually can Give you a summary of your genetic risk and whether your genetic risk is high, medium, or low relative to the general population.

So these polygenic risk scores are really emerging as potential tools for for further gi, for giving women more information about whether their risk is higher than average and whether they should consider mammography. Sooner more often or screening with other more sensitive technologies like ultrasound or mri.

So I think that’s gonna be coming down the pipe soon. It’s, you can’t get polygenic risk score run right now. Like if you ask your doctor about it, they’re not gonna know what you’re talking about. It’s not out there clinically yet. But we are doing a lot of research in that realm and I think that next Next several years, that might be something that come, comes out to a broader degree clinically.

[00:21:17] Adam Walker: That’s exciting. So, so talk to me about how racial and ethnic disparities factor into your research surrounding prevention

[00:21:25] Dr. Anne Marie McCarthy: and screening. Yeah. Racial and ethnic disparities are an important important and sad thing that we need to consider when we are talking about breast cancer. While we’re doing a lot better at treating breast cancer, breast cancer mortality has fallen over the past several decades, and that’s true for all patients.

But not all patients have benefited equally. Mm-hmm. Black women in the US have 40% higher breast cancer mortality than white women. And that disparity has really stayed stable over time. We haven’t really cut into that disparity very much. And so we, we believe that’s partly due to systemic racism and challenges to accessing healthcare challenges across the life course in terms of getting both exposures over the lifetime as well as getting access to care and prevention.

So that’s definitely something that, you know, we need to work broadly to improve improve health and access to health across all conditions. And for breast cancer we do that. We do need to do that as well. However, we also know that there’s differences in the types of breast cancers that occur in different populations.

And so, there’s different subtypes of breast cancer. You’ve probably heard about those on the podcast before. So, e r P are positive. Her two negative is the most common breast cancer. There’s also breast cancer called triple negative breast cancer, and those are cancers that don’t express estrogen receptor, jestin receptor, her two receptor.

And so until recently, patient. Really couldn’t take the drugs that we give to patients with the other types of cancer. And so prognosis was poor. Triple negative tends to be more aggressive. And it also seems to be less likely to be detected on a mammogram, more likely to show up in the screening ural.

And unfortunately black women are much more likely to get triple negative breast cancer than white women. We had a study that showed, it was about. Two to three times more likely to get triple negative breast cancer. So we think that this the differences in subtype likely likely contribute to differences in breast cancer outcomes.

And so when we’re bringing it back to thinking about risk most of the work that we’ve done, most of the breast cancer research that has been done over the past several decades has been done among white or European ancestry populations. And so while some of those risk factors are what are.

Definitely still important for black populations. There might be some factors that are different. There might be some factors that are more important for one population than another that we’re not considering to the extent that we need to. And so in my work at Penn we have a very diverse patient population and so we’re really focused on.

Doing our research and on and personalized screening and including diverse populations, black women and white women to make sure that the recommendations we’re making work well for all women. And so there might be some tweaks we need to make in terms of the age or how frequent or, you know, maybe risk factors we need to look at, might differ.

And so we’re. Actively trying to figure out how to do things better and how to do precision screening in a way that can actually reduce disparities rather than make them worse.

[00:24:45] Adam Walker: That’s fantastic. I’m, I’m so glad that’s on your radar and you’re doing that work. So important. We talked about that so many times on this podcast, but it’s always good to reiterate those factors.

And again you mentioned several things that I did not know in that answer, so I really appreciate that. So, last question. Do you have any final advice for our listeners who might be approaching the recommended age for screening and that are trying to assess their breast cancer

[00:25:09] Dr. Anne Marie McCarthy: risk? Yeah, so as I mentioned before, be informed, which everybody who’s on this podcast is starting that out.

Go down the line. There’s some breast cancer risk factor questionnaires online. Komen might have some links. There’s a few others, so. You know, ask your family members, anybody have breast cancer? What kind of breast cancer did you have? How old were you when you had the breast cancer? That’s another thing I didn’t mention.

If you have cancers occurring earlier in life, that’s more indicative of genetic risk versus if cancer’s diagnosed later in life. So gather the information look on, you know, look up and see what are the, what are what’s covered by insurance in your state, what’s recommended? If next time you get a mammogram, what’s my breast density?

And then if you’re coming up on screening, agent deciding, should I be screened now? Should I wait? I would definitely schedule a well visit with your primary care provider and come up with a list of things you want to talk about and tell them. Primary care providers are great and they’re really our first line of defense against.

All health conditions, but they’re trying to take care of all health conditions. So, if they forget to ask you about your family history or they forget to ask you about a mammogram, don’t assume that it’s not important. You know, really, you know, put it on your list, put it, I always put a note in my phone when I’m going to the doctor with the thing out, things I want to talk about.

And be sure to say, Hey I’m almost 40, or, Hey, I’m almost 50, or, Hey, I’m this age, I haven’t. Gram, I’ve been having my mammogram every other year. Should have it every year. I’ve been having it every year. Do I need it every year? Ask your doctor to talk about it. If you have family history, make sure you tell them and tell them about all your family history for cancer.

So, breast cancers, but also ovarian cancers, pancreas cancer, prostate cancer. So BRCA mutations can increase the risk of all of those types of cancers. So, You know, and just thinking more broadly, you know, it’s a good idea if you’re coming up in, in your forties or whatever, go to primary care and say I’m almost 40.

What about my cancer screenings, breast cancer colorectal cancer cervical cancer, you know, if you’re a longtime smoker, lung cancer screening. So, you know, take a little bit of initiative and ask your doctor about it. And then I’d also say, Yeah, just stay stay informed, stay tuned. Because things are changing for the better.

I think we’re at a really exciting time in cancer research. I think we’re making a lot of great discoveries. We’re learning a lot about how we make the genetics impact people and reduce reduced seas. So I think it’s a really exciting time, but, you know, Stay on the podcast cause there’s going to be a lot a lot of new stuff coming out that we need to team to know about.

[00:27:51] Adam Walker: Yeah, there is. That’s right. That’s right. Stay on the podcast. Keep subscribing . That’s right. Well, Dr. McCarthy, this is, I mean, this has been great. I mean, I, I really appreciate the research that you’re doing and, and I appreciate all the new things that I learned in this conversation, even after having so many conversations.

I learned quite a few things in this one, and I really appreciate you taking the time to join us today and and share your knowledge.

[00:28:12] Dr. Anne Marie McCarthy: Wonderful. Adam, thank you so much for having me. It’s great talking with you.

[00:28:20] Adam Walker: Thanks for listening to Real Pink, a weekly podcast by Susan G Komen. For more episodes, visit RealPink.com. For more on breast cancer, visit Komen.org. Make sure to check out at Susan G Komen on social media. I’m your host, Adam, you can find me on Twitter @AJWalker or on my blog, AdamJWalker.com.