0:00

So this is like the whirlwind

0:02

tour of contrast-enhanced mammo.

0:03

We're gonna move on to CEM and clinical practice.

0:06

Um, let's start here.

0:09

So, um, there are a variety of clinical

0:13

indications for contrast-enhanced mammo.

0:15

These are all diagnostic indications,

0:18

as you'll notice, because I mentioned it's

0:19

only approved in the diagnostic setting.

0:21

And the last one on this list is

0:23

high-risk supplemental screening.

0:24

And that's because, um, there are new

0:26

recommendations that are allowing us

0:29

to do contrast-enhanced mammo in this setting,

0:31

but it is not FDA approved, or at least allowing, as I

0:34

should say, recommending as an alternative to MRI.

0:36

And I'll get into that. For this talk,

0:39

we're gonna focus on these first three, um,

0:42

indications: cancer staging, evaluate neoadjuvant

0:45

chemotherapy response, and recall from screening.

0:51

So this is the first case.

0:52

Finally, some pictures.

0:54

This is a 68-year-old woman who is recalled

0:57

for right breast architectural distortion.

0:58

I'm not gonna show you the tomo images.

1:00

You can see the distortion is

1:01

here, marked by the yellow arrow.

1:05

When we do the recombined images, you can

1:07

see that there is a discrete mass here.

1:09

And so this, this contrast mammo allowed us

1:12

to both characterize the finding and also

1:16

delineate extent, and that's really one of the, uh,

1:19

beautiful things about this imaging modality.

1:21

It allows us to do both right at

1:23

the time of the diagnostic exam.

1:25

You can also do this after biopsy.

1:29

So this was a grade 2, uh, hormone

1:31

receptor-positive breast cancer.

1:34

This is another case.

1:36

This is a 68-year-old woman who was recalled

1:38

again for right breast architectural distortion.

1:40

This is the area of distortion.

1:42

It was a very subtle finding,

1:44

not even worth showing you the 2D images

1:45

for this particular case.

1:47

These were the recombined images that showed us for

1:49

sure that there's an abnormality in this location.

1:52

But it also showed us that there were other

1:53

abnormalities located in both breasts.

1:55

These were all malignant.

1:57

So this is an example,

1:58

uh, for sure for architectural distortion.

2:00

It helps us say, is this area

2:03

something to worry about or not?

2:05

And is there additional disease

2:08

in other parts of the breast?

2:09

We had an MRI again, because this was, um, during

2:12

the earlier parts of our implementation,

2:15

and you can see that these findings showed up on

2:17

the MRI as well, and they were all malignant.

2:20

So again, this really just highlights, um, how

2:22

similar the images are that we see on those

2:24

recombined images to our MRI images, which is really

2:27

why the sensitivities of the exam is so similar.

2:32

This is another exam, but we've

2:33

talked about distortion so far.

2:35

This is a mass.

2:36

This is a 75-year-old woman who had a history

2:38

of bilateral breast cancer and recalled, uh,

2:40

for diagnostic CEM for this right breast mass.

2:43

Now, this is— what I like about this case.

2:44

We can all see the mass that's

2:45

marked by the yellow arrow.

2:47

But what I liked about this case and why

2:49

I'm showing it is because we know that,

2:51

once you have cancer treatment,

2:53

it can distort the breast.

2:54

It can be difficult to figure out what is just

2:57

related to the surgery and what is new that

3:00

we need to worry about and remove or treat.

3:03

And so what the recombined images did for us

3:06

is they just showed us where the cancer was, and

3:10

all of those other areas of distortion related

3:11

to the post-surgical changes just disappear.

3:14

And this was a grade 3, uh,

3:16

hormone receptor-positive cancer.

3:20

This is another, um, example of contrast mammo.

3:23

This was DCIS.

3:24

This is for calcifications.

3:25

And calcifications are different than

3:27

distortion, mass, and we'll talk about that.

3:29

This was a patient with DCIS.

3:30

You can see it was already biopsied.

3:32

That was the clip.

3:33

These are the calcifications.

3:34

Linear branching.

3:35

Very, very suspicious, right?

3:38

Not surprising.

3:38

This came back as DCIS.

3:40

This person couldn't get an MRI for disease

3:43

extent, so we did a contrast mammogram.

3:47

And what you'll notice is that the

3:49

recombined images show no enhancement.

3:52

So this is an example, and the reason

3:54

why I'm include—I'm including it,

3:56

this is an example still of a positive contrast mammo,

3:59

because it's showing those calcifications even though

4:04

it's positive, even though there's no enhancement here.

4:07

And this is one of the challenges of

4:09

contrast mammo for calcifications, where

4:11

some DCIS, low-grade invasive ductal

4:13

cancers might not show enhancement.

4:16

We have to act on it anyway.

4:18

So when thinking about cancer staging for

4:19

calcifications, we don't actually use the

4:22

recombined images to help us determine whether

4:25

to do something about the calcifications.

4:28

It's really to see, is there enhancement

4:31

separate or beyond the area of calcifications

4:33

that might impact the overall treatment plan.

4:38

So in summary, here are a few, um, studies

4:40

that I'm just pulling out from the literature.

4:42

Sumkin et al. in 2019, they compared CEM to MRI for

4:46

cancer staging, and they found that the sensitivities

4:48

for the primary cancer site are 93% versus 91%.

4:52

And if you were to look through the literature,

4:53

you would see this over and over again,

4:55

these sensitivities being very similar to each other.

4:59

Um, and they also found that both imaging

5:02

modalities, CEM and MRI, overestimate the

5:04

tumor size, um, to a similar degree.

5:06

And this overestimation is by a few millimeters.

5:09

We are not talking about centimeters,

5:11

um, here. Lobi et al.,

5:13

uh, more recently were looking at contrast-enhanced

5:16

mammography and MRI, uh, and it's evalu—their evaluation

5:19

of ILC, which is invasive lobular cancer, and found that

5:22

both of them overestimate ILC by around two millimeters.

5:26

Very similar.

5:27

And then Lee and colleagues in 2021—

5:29

look, didn't—you know, I'm, I'm providing, um,

5:33

information not on how well they found the cancer,

5:37

but on what the positive predictive value, which

5:39

is really how well, when you see something in

5:42

contrast mammo or MRI, is it likely to be cancer?

5:45

And you'll see that the positive predictive

5:47

value is much higher for CEM over MRI.

5:49

And this, again, is kind of borne out over and

5:52

over again, which is when you see an abnormality

5:54

on contrast mammo, it is more likely to be breast

5:57

cancer than when you see an abnormality on MRI.

6:00

And this, um, likely is because again,

6:03

it's a 2D—it's a, it's a planar projection.

6:06

So if it—it becomes obvious

6:08

enough for us to see it, um—

6:11

then we should act on it, uh,

6:14

to a greater extent than with MRI.

6:16

And, um, yeah, that's the main—that's

6:19

mainly what I have to say about that.

6:22

So, in general though, the take-home point

6:24

is that contrast-enhanced mammography

6:25

can be used as an alternative to MRI.

6:28

So forgetting, you know, the data is there—

6:31

and this is what you should remember.