To help PCPs address patients’ breast cancer screening concerns, surgeon Shoko Emily Abe, MD, FACS, breaks down the multitude of screening directives and modalities, with a focus on the needs of those at average risk and those with dense breast tissue. She offers current data informing when to start mammograms; discusses the advantages of tomosynthesis; and clarifies when other methods, such as MRI and ultrasound, are useful. Bonus: Empower patients to find their own screening schedules through the WISDOM Study.
Thank you for having me. Um, first of all, um, kudos to you all and thank you. I think, uh, a lot, a lot of you are, are, are primary care physicians, correct? And I know you are all the ones faced with this conundrum of what is the right screening modality and timing and age to start, and I think it's It's such a heated topic because it's true that there is no right answer. And just to jump to the conclusion, in the end, it is an individualized decision-making process, um, but hopefully I can answer or at least kind of give some different types of insight to the idea of breast cancer screening and then specifically also talk about what to do with patients with dense breasts. Um, so, to start off with, again, we'll talk about um reviewing recent guidelines, um, briefly. Um, but talk about mammograms with, uh, tomosynthesis or 3D mammograms, breast MRI, and other breast imaging for breast cancer screening, and then again, talk about how that may apply to women with dense breast tissue. So I put this up here from the CDC only because you could see that there's so many guidelines out there that we can follow, and it's broken down here, you know, these are for average risk women, and it's broken down here by age group 40 to 49, 50 to 74, and also women above 75, and what to do about women with dense breasts. So, I'm not going to go through these one by one. Obviously, you could still see this on the CDC website, but they're very, somewhat disparate in different recommendations, um, and a lot of this is based on what is kind of the data that they've looked at, um, and what is the ultimate idea about what they want to achieve for women, um, in terms of breast cancer screening. So, With all that said, Uh, you know, breast cancer screening for average-risk women. Um, I know a lot of you follow the US Preventative Services Task Force recommendation, um, which I think is what, what most primary care physicians follow in this day and age. Um, talk about individualized decision making from age 40 to 49, and then biannual screening from age 50 to 74, and then consideration about not necessarily recommending and saying that there's no real evidence to say that women after age 74 should or should not get. Mammograms and it's really again an individualized decision at that point as well. And these recommendations are basically based on kind of this idea that annual screening can cause a lot of anxiety. Um, there's the thing to consider, especially in the women starting at age 40 of the radi radiation exposure yearly. Um, Again, in that age group, there are more false positives which lead to increased biopsies, overdiagnoses, and possibly overtreatment, and that's been always a controversial topic in breast cancer to begin with as well. I do want to point out that there are some things that are kind of flawed in the US Preventive Services Task Force kind of um analysis of the data, but, um, so basically, there's underestimation of benefit in the age 40 to 49 group, um, because they used more heavily the flawed Canadian trial data and excluded some of the large population-based studies. But they did update their recommendation in 2016 to include these observational studies, some of the biggest studies that we have out there that did show a benefit. To mammogram screening in that women in the 40 to 49 age group. Um, and so they did acknowledge, acknowledge that starting, uh, annual screening at age 40 did save lives, but again, still remains the issue of more false positive rates leading to increased biopsies, over diagnosis, overtreatment. So again, it's always kind of this balance of, you know, the risks and benefits, which is, I think, a conversation that as physicians, we always have with our patients because, of course, you could do everything under the sun, but is it really going to be beneficial for you? Um, and I know that's kind of the hard part for talking to my primary care colleagues and friends. You know, having the time to go through this and do a risk assessment is, is, I'm sure, the difficult part because you have to talk about everything else. I'm sure the colon cancer screening, are your vaccinations up to date, all the other things that you have to cover during a wellness visit. It's, it's, it's quite extreme. I think my visit myself with my primary care doctor was, you know, definitely close to an hour. If not, she might have gone over just to go over everything. Granted, she didn't touch upon the breast cancer screening part as much with me, but It's a lot to go over and to go over this kind of individualized screening process would be a lot. Um, nevertheless, some of the recommendations that, you know, we as breast surgeons follow, kind of follow the American College of Radiology and the American Society of Breast Surgeons, which starts with that simple annual starting at age 40. Um, and then consider even supplemental imaging if they have dense breasts, meaning either MRI screening or ultrasound screening. Now, a lot of people will say, isn't that a little bit of conflict of interest? Um, I've heard, uh, uh, people make comments, especially when maybe a radiologist is giving this talk about, well, isn't it a conflict of interest for you to say you should all start mammograms at 40 when obviously these people are coming to you in your department for imaging. Um, but nevertheless, that, that has been the recommendation, uh, for a long time. The NCCN guideline, the National Comprehensive Cancer Network guideline, which is kind of the, the cancer treatment bible, if you will, um, also talks about annual screening for average-risk women, um, once they reach 40, um, and to, um, always consider tomosynthesis, a 3D mammogram, um, and I'll touch upon that a little bit in terms of, uh, dense, uh, breasts. And I feel like the American Cancer Society recommendation kind of It is a kind of a good in-between point between these recommendations and the US Preventive Services Task Force recommendation. In terms of saying from 40 to 45, an individualized decisionmaking process definitely makes sense, because the risk of a woman in their early 40s getting breast cancer is statistically pretty low, but to consider annual mammograms starting at age 45 and at 55, go on to biannual mammograms. I do want to stop and talk about the biennial mammogram recommendation once you reach your 50s or 55. Um, I don't know if you all do this, but I, I've definitely have been over the years telling patients that this recommendation for biennial mammograms seems like, makes it sound like your risk is decreasing as you get older, um, and therefore, you could do it every other year. But the fact of the matter is, the patient's breast cancer risk as they get older continues to creep up. You know, that 12% lifetime risk is really a statistic we're talking about when they're reaching, you know, their um eighties. And so, I tell patients, I don't want you to get a false sense that, oh, my risk is going down as I got older and therefore I could just go every other year. The fact of the matter is their risk is actually creeping up gradually as they get older and older, but the type of breast cancer they tend to get tend to be slow growing and therefore biennial mammograms, every other year mammograms should be fine in terms of catching a slow growing mammogram, which is not going to suddenly become a stage 2 breast cancer in a matter of months or even a year. Having said that, obviously there are A portion of postmenopausal women who do develop more aggressive breast cancers that develop even before, you know, their next annual mammogram is due, meaning 6 months after their mammogram, they're like, I was told it was all clear, and suddenly you have this lump and you're telling me it's cancer, and they're a little bit surprised. Now granted that population in the postmenopausal women population is probably somewhere around 10 to 15%, so it is true that it's not the majority. But there will be women who, if they twitch to biennial, will have aggressive breast cancer mists, or at least they're only going to detect it because they felt it themselves. So, um, I think the big question is, is breast cancer a significant health problem for women in their 40s, you know, who tend to have dense breast tissue. So 45,000, 45,280 cases of breast cancer were found in women aged 40 to 49 in 2019, so that's 1 in seven total cases of breast cancers in this country. And it's interesting to note that there's a younger age peak in minority women or women of color, and I'll show you a graph in a second that'll kind of really drive this home. But you see these lines here, um, women, Hispanic women, Asian women, and black women, their peak is here before the age of 50 versus in white women, we are talking about that, you know, 65 or so average age that um they get breast cancer. So that's another kind of piece that we want to keep in mind when we talk about when should you start screening mammogram, and I know this has shifted also as well in terms of colon cancer screening, especially for our black patients. So keep that in mind also in terms of breast cancer screening. So they're diagnosed with more advanced stage, even under the age of 50 when they're diagnosed, and among women dying of breast cancer, minority women are 127% more likely to die before the age of 50. So again, a reason for this population specifically to maybe consider starting early, and we'll talk about other again the supplemental imaging, but Um, I don't want to go into this too heavily. It might be a little bit of a plug. It's not a UCSF study, but when we talk about personalized screening, Um, and how do you determine and, and figure that out? This wisdom study, which is a study offered nationwide, it is not specific to UCSF and it's not specific to women having to come to UCSF for imaging, but we are kind of spearheading this. Um, the question has been, you know, how do you personalize the screening regimen? And this study, um, basically assesses someone's personal risk by looking at Breast density, lifestyle, family history, and genetic factors. They will do genetic testing if the patient qualifies. And it's a randomized trial. However, patients can be, can choose to kind of choose their screening modality and be in an observational cohort. So this is something that um you might want to consider telling patients about so they could actually go ahead and have their own personalized um uh breast cancer screening regimen figured out. So the, I have the website on here, here, the wisdomstudy.org. Um, that is something that you could direct the patients to. It is patient-facing website. And again, it is offered nationwide. Um, patients can get their mammogram anywhere they choose to, and it just asks for surveys to be filled out for them to undergo this risk assessment and then for them to turn in their, uh, mammogram screening results. Um, so I want to jump into kind of dense breast tissue, um, and I'll talk about a little bit more about some of the more recent trials, but, um, 3D mammogram or tomosynthesis mammogram has been a big, big positive, um, especially in women with dense breast tissue, because the problem has always been in the, even in the days of digital mammography, women with dense breasts, extremely dense breasts, which are usually women who are premenopausal, you can't really tell what's what because it's just almost a complete whiteout. But that you could see kind of in this mammogram over here, that's a 3D mammogram. There's a lot of dense breast tissue, as when it scrolls back out, I'll kind of point out this whole whited out area. And you can't tell what's what until you scroll through with this 3D mammogram and you saw this area of distortion here, what we call kind of an array of architectural distortion with maybe a more distinct mass here with some speculations. So 3D mammograms, first and foremost, decrease the callback rates. Um, that was one of the first important things. So essentially, potentially decreasing the false positive rate. And then we're finding furthermore that it has improved cancer detection, so it definitely has made mammogram more specific and more sensitive. So that was a big, big positive for, for mammography and especially for women who have dense breast tissue. And again, even the NCC guidelines says to consider tomosynthesis, and I would say in our Bay Area, it's pretty much the gold standard. Almost any breast center or a place that offers mammography is going to order 3D, uh, offer a 3D mammogram or uh tomosynthesis mammogram. Again, the American Society of Breast Surgeons consensus statement also states that tomosynthesis is the preferred modality, especially in younger women and women with dense breasts. Um, but it's true that it hasn't been studied sufficiently to determine if it actually improves, improves disease-specific mortality. Uh, there are a lot of questions about the higher radiation dose potentially with 3D mammograms, but it's actually pretty minimal, and it's, it can be minimized with syn synthesized 2D reconstructions, meaning the patient doesn't have to get a regular 2D digital mammogram and then get the 3D mammogram on top of that. Um, and of note, it is still much lower uh radiation than other breast cancer screening modalities that are being developed like breast-specific gamma imaging, sesame scanner, PET scans. So when it comes to dense breasts, really, MRI has been probably the biggest kind of positive, if you will. And again, as I showed in the earlier kind of guidelines that are out there, there aren't really any that specifically say, yes, add MRI screening to dense breasts, but we do know the benefit of um MRI screening for women with dense breasts, and this certainly has been um a little bit more well studied in women who are considered high risk. So again, the American Society of Breast Surgery consensus statement says consider supplemental imaging such as breast MRI in women with dense breasts. Um, again, it's not currently standard of care for average-risk women, so obtaining insurance authorization, etc. could be difficult. Um, We also recommend MRI screening for women diagnosed with breast cancer under the age of 50 or who do have dense breasts, and otherwise, it is utilized in women who are high risk. Now, The, the I guess the, the issue with breast MRIs is that it's also not offered everywhere or it's not easily accessible for all women. And so a lot of our consensus statements, for instance, say, you know, supplemental imaging with breast MRI is the preferred modality if you have dense breasts. However, if that is not available, um, potential consideration for ultrasound screening. Um, would be, uh, another option. However, this again is recommendations for high-risk women, and from my understanding, at least in this area, bilateral screening, um, breast cancer screening for um breasts with ultrasound is not something that's recommended or offered at radiology centers, and it has to do with the fact that there's actually very little data to say that it, it's a good screening modality. Um, Ultrasounds on the breast are a good. A diagnostic tool, meaning if there is a palpable mass or a very specific point on a mammogram that looks abnormal that looks like a mass, an ultrasound as a targeted study is very good, but as a screening study when they're just kind of screening all, you know, over the breast through the entire breast on both sides, there are a lot of false positives and a lot of artifact, and it's very operator dependent. So in that sense it's not. The best screening modality and even in women with dense breast tissue. Um, I will say there was a study out of Japan that added ultrasound screening on top of mammogram for women with dense breast tissue. So this is a very, very specific population of Japanese women, but they did find that the addition of supplemental ultrasound increased the cancer detection rate. Um, I think we have to take that with a grain of salt in our patient population in the US because Japanese women tend to be a lot smaller, much more petite. Usually their breasts are much smaller, so ultrasound screening, just the technical feasibility of it is much different as well as just kind of the time that it takes. So that might not really apply to our patient population in the US. So that's something to keep in mind. Um, uh, oh, I just kind of talked about the screening, uh, breast ultrasound. Um, but thermograms are another thing that you might hear patients ask about, like, is this, is this good? Is this better than mammograms since mammograms aren't good for dense breast tissue. Um, unfortunately, there is no real evidence showing that it's equivalent in sensitivity or specificity to mammograms, so it is not a modality that we recommend. It is FDA approved in terms of it's safe. Um, but ultimately if anything is picked up on a thermogram, they're going to tell you, you know, to go get a mammogram anyway. Um, unfortunately, the sensitivity and specificity of this is, is pretty low in terms of comparing head to head to mammograms. Um, oh, you know what, I didn't have that last slide on in here, sorry. Um, so, specifically talking about some of the more recent data that's out there regarding dense breast tissue, um, there was a study, uh, called the dense trial out of the Netherlands, um, that looked at, again, supplemental MRI screening. On top of mammography, and so it was a randomized multi-center trial and just to jump to the conclusion, it did show that there was a higher cancer detection rate of what we call interval cancers, meaning the MRI was able to detect cancers that mammograms were not detecting. Now I know this doesn't quite answer the question that you had about what do we do about just mammogram screening when this report comes back as Dense breast tissue, you should, you know, consider yearly mammograms when you are otherwise told this average-risk woman who's maybe 45 to just, you know, consider maybe every other year or to not even start, but nevertheless, I think This is where I guess that conversation about what, what does it mean for the patient to undergo the mammogram and potentially have a higher chance of false positive, meaning telling them you have a higher chance that they're gonna maybe think something, they see something and they're gonna ask you to come back and do a diagnostic mammogram and ultrasound and possibly say, yeah, that's probably benign, but let's biopsy it just to make sure, or yeah, that's probably benign, but let's still have you come back, come back in 6 months for another diagnostic mammogram and ultrasound. And so they're put into this cycle of potentially undergoing a biopsy that perhaps will show a benign result, but nevertheless they have to go through this process of a procedure which has its attendant risk, which, although minimal are still risks as well as just the anxiety that it does cause, and I think these are conversations I have with patients too who typically are sent to me because they are potentially high risk, meaning they have family history or some other issue that You know, warranted a visit with a breast surgeon, but it's still conversations I have when we talk about, well, you're not high risk, but what should your screening frequency and modality be. And I think these are hard conversations and, you know, the patient response runs the gamut from, well, if you're telling me, you know, I'm average risk, I'm OK just, you know, starting at 45 or 50, and I'll make sure I get my mammogram and I'll still check myself periodically. And then I certainly have a lot of women, women who are like, you know what, I'd rather know than not know, so I'm going to do my yearly mammogram. So, you know, it still again puts you all in a, in a difficult position of how what do you recommend without going into like a 30-minute conversation, but it certainly comes down to, look, in the end, both are not wrong or, you know, whatever guideline you choose to follow, but it is really about understanding what is the potential downside of potentially starting at a younger age versus what's the downside of maybe starting at an older age, um, or not doing it yearly. And again, it just falls back to kind of that individualized decision-making process. And again, if you have patients who might be potentially higher risk, whether it be from family history, um, had an odd biopsy showing atypia at some point, um, They haven't had children, etc. Anything that might make you think they might be high risk, you know, refer them to perhaps your local, you know, breast center or breast surgeon or your OBGYN colleagues who may do risk assessments to really figure out what is the right screening interval and modality for your patients.
