0:00

So why not more breast MRI?

0:02

These are kind of old numbers,

0:03

but it's really about dollars.

0:07

Um, an MRI costs a lot.

0:09

Um, look at the private billing, um, number 3,

0:13

000 versus a mammogram or a breast ultrasound.

0:16

So how can we make this less expensive?

0:18

Also, according to Berg et al,

0:21

they're not always well tolerated.

0:22

You know, there's claustrophobia.

0:24

There's also contrast given.

0:25

That's a, you know, some for

0:27

some, that's not a good idea.

0:30

And in terms of full protocol, the same

0:34

protocols are used for diagnostic and screening.

0:36

Some people worry about catalytic deposition.

0:38

We're not as concerned about that.

0:40

I think now, but how can we make this more

0:43

efficient, more cost-effective as well?

0:45

So, what about fast or abbreviated MRI?

0:48

So.

0:49

This is all about early enhancement, abbreviated

0:52

MRI, and that early enhancement ratio is

0:56

a measure of the contrast wash-in, and it

0:59

correlates nicely with lesion conspicuity.

1:02

Earlier enhancement, higher conspicuity,

1:06

and it also, interestingly, relates

1:09

to tumor grade, a proliferative index

1:11

of KI 67, and aggressive tumor grades.

1:15

And so leveraging that early enhancement is the

1:20

Early enhancement is seen in bad

1:21

prognostic cancers and less often in

1:24

false positives or low-grade lesions.

1:26

Remember that.

1:27

Maybe imaging late, delayed scans, as

1:31

in full protocols, maybe that increases

1:34

false positives and lowers specificity.

1:38

So, here we go, here's a full protocol, um,

1:41

MRI, you know, it has a T2, a precontrast T1.

1:44

We do diffusion at our site on all patients.

1:47

Then we do three post-contrast

1:49

and sometimes even a fourth one.

1:51

And then there's the reconstruction,

1:52

which isn't a table-time activity,

1:54

but, you know, we have to consider it.

1:57

What sequences are absolutely essential?

1:59

Well, you need the T1.

2:01

And you need the post-

2:02

contrast, the pre and the post.

2:05

Maybe you need the T2.

2:07

We'll talk about that a little bit later on.

2:09

And so the abbreviated protocol that we

2:11

use right now is a T2, a pre-contrast

2:13

T1, and then one post-contrast.

2:17

And then the reconstruction, of course, is done.

2:20

So, the abbreviated protocol again, Christiana

2:23

Cole, great stuff, did a prospective trial.

2:25

These were high-risk women

2:26

with a negative mammogram.

2:27

Remember, high-risk women who had

2:29

had, um, had some annual screens.

2:33

They had a full scan as well as

2:35

the abbreviated protocol read.

2:37

This is what her abbreviated protocol.

2:39

Notice there is no T2 in this.

2:41

Pre-contrast, post-contrast, a subtraction

2:44

created post, you know, um, you can do that later.

2:46

And then a MIP.

2:47

Okay.

2:47

Fusing all of subs.

2:49

Results, she looked at table times,

2:52

both table time and read time decreased

2:54

between the fast versus the full.

2:56

She did her fast in three minutes.

2:58

That is super fast, but remember she didn't have

3:01

a T2, and that's the longest of the sequences

3:04

to do versus 21, which is very fast for a

3:07

full, and the read time she even compared.

3:10

I don't know.

3:10

That's pretty fast.

3:11

2.8 seconds for looking at the MIP.

3:11

83 00:03:13,970 --> 00:03:15,750 28 seconds for the subs.

3:16

All 11 cancers were detected by both studies.

3:20

10 on the MIP of the FAST.

3:21

Just looking at the 8 seconds.

3:23

I don't know if I could do that really.

3:25

But anyway, and 11, um, when

3:27

the whole fast was looked at.

3:29

So sensitivity, very, very good

3:31

additional cancer detected.

3:33

And this is high risk 18.

3:34

2 per 1000 cancer detection rate.

3:37

Look at this.

3:38

I alluded to this early specificity was similar

3:41

with the abbreviated MR versus the full MR.

3:44

Actually, in her small study, the

3:46

specificity was a little bit better.

3:48

Look at that 94.

3:50

3 versus 93.

3:50

9, not statistically significant.

3:53

But, you know, when you're looking at breast MRS,

3:55

sometimes those things that are very late, delayed

3:58

and enhancing, they may be the false positives.

4:01

There's certainly the lower grade cancers.

4:03

I still believe in finding those, but

4:05

interesting about the specificity.

4:07

PPV pretty good on similar full

4:09

versus abbreviated protocol.

4:12

So then we roll into the very famous Akron

4:15

1141, comparing a true abbreviated MR, um,

4:19

to tomosynthesis now, not just 2D mammography

4:23

in average risk women with dense breasts.

4:26

That means heterogeneous

4:27

or extremely dense breasts.

4:29

There were 14, um, when this was published, and

4:31

this was 2020, there are now new data coming

4:34

out on sequential rounds in this Akron 1141.

4:37

Um, But in this 1st publication,

4:41

there were about 1400 women.

4:43

They got both Tomo and the

4:45

abbreviated in a randomized orders.

4:47

And the studies were interpreted by 2

4:50

different radiologists independently and

4:53

then they were screened twice 1 year apart

4:55

and followed for 3 years for outcomes.

4:58

And in their analysis, PyREDS 5

5:01

were considered positive results.

5:02

So what we have here is the first year

5:05

in that publication, there were 23 women

5:07

diagnosed with cancer, 17 invasive, 60 CISs,

5:11

the abbreviated MR found almost all of them.

5:15

There was one that was found by the tomo.

5:17

It was an er, negative high grade DCIS, DYS calcs.

5:20

So again, important to have both the mammogram

5:23

and the abbreviated MR of the 14 seen only by MRI.

5:28

Um, again, that one was not seen.

5:30

So here you can look a little

5:32

bit at the, uh, histology.

5:34

This is the cancer.

5:35

Um, comparing the two and you

5:38

can see DBT had, um, 14 negative.

5:42

tests where cancer was found by the abbreviated M.

5:45

R.

5:46

Nine positives tests by the D.

5:49

B.

5:49

T.

5:49

And again on the abbreviated M.

5:51

R.

5:51

You had that one cancer that was the D.

5:53

C.

5:54

I.

5:54

S.

5:54

found by mammography D.

5:56

B.

5:56

T.

5:57

But not on the M.

5:58

R.

5:58

I.

6:00

So, sensitivity, we compare, look at that, almost

6:04

96 percent sensitivity with the abbreviated MR.

6:08

These are women with dense breasts.

6:09

So, you know, the sensitivity is not great.

6:11

39 percent only.

6:13

Specificity, again, not as good with abbreviated

6:16

MR because you're going to see other things

6:18

because of the contrast and the enhancement.

6:20

PPV of biopsy still acceptable

6:22

with the abbreviated MR.

6:23

Additional.

6:24

Imaging, like, come on back, I need to

6:26

see, I need to do mag views or whatever,

6:28

with the tomosynthesis ultrasound needed.

6:31

Um, and there were cases in the

6:33

abbreviated MR where additional imaging

6:35

was recommended to see if lesions were

6:37

seen and ultrasounds performed as well.

6:40

So, characteristics of the

6:41

cancers very, very important.

6:43

This is looking now at the mass, uh,

6:46

the, the max histology of the invasives.

6:49

And look here.

6:51

Abbreviated MR, look at that.

6:53

There were low grade, intermediate

6:54

grade, and high grade.

6:55

Um, and then the combination

6:58

you can see on the far right.

7:00

And then you see the max histology for DCIS

7:03

again, more commonly, more aggressive lesions

7:07

with the abbreviated MR protocol than the DBT.