0:01

So while BI RADS 3 is a challenging topic overall, I think that

0:05

MRI is really the hardest topic with BI RADS 3 because it's a

0:09

newer field and the data is a lot less robust than on mammogram

0:13

and ultrasound. I did show a few examples of some cases that there

0:18

is some data to support the use of BI RADS 3 and I

0:21

just want to go over those. So just to start, like I said,

0:25

this is really an evolving area and I think we want to be

0:29

flexible with our use of BI RADS 3 on MRI and be following

0:33

the literature because I think that this is going to be really clarified

0:36

over the next couple of years. The fifth edition of BI RADS was

0:40

published in 2013 and MRI has, the technology itself has improved since

0:46

2013. We're also just doing a lot more breast MRI

0:51

now than we were in 2013. So this is becoming more and more

0:55

relevant. But the 2013 atlas, this is what it lists for reasons to

1:00

give a BI RADS 3 on MRI. So first it includes background parenchymal enhancement.

1:05

In the atlas it says to consider giving a BI RADS 3 when

1:08

there's suboptimal timing based on menstrual status or for postmenopausal

1:14

patients on hormone replacement therapy. They include a

1:19

dominant focus that is T2 hypo intense on baseline MRI

1:24

and for masses and oval around circumscribed mass on a baseline MRI.

1:29

And then they say that in the atlas it says that there's insufficient evidence

1:33

for non mass enhancement. So there's emerging data that, you know, this

1:39

is not in BI RADS yet. And hopefully when a new BI RADS comes

1:42

out, there'll be better guidance. But the more updated literature suggests

1:47

that we don't need to use BI RADS 3 for background parenchymal enhancement.

1:51

There is with the newer contrast agents, we have not shown that there's

1:56

large variations in the timing based on menstrual status.

2:02

And we should really, if we see a diffuse pattern of background parenchymal

2:06

enhancement, we should be able to assess that as a BI RADS 2. If

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there's any areas that stand out and look separate,

2:14

we should give it a BI RADS 4 and do a biopsy.

2:17

But that the space for really doing a short term follow up for

2:19

background parenchymal enhancement has really gone away. The foci in mass,

2:25

the data has continued to support those two, and I showed examples of

2:28

these two findings that are reasonable for a BI RADS 3 assessment. So

2:33

just to repeat again, we see a dominant focus, so this should be

2:37

a single focus that stands out compared to the rest of the background

2:41

parenchymal enhancement. And it should be T2 hypo intense, and it should

2:47

be on a baseline MRI or one with less than two years of

2:50

follow up. We're going to follow it for two years. If it's T2 bright, then

2:54

we can consider that benign. And if it's a new or increasing

3:00

enhancing focus, then we want to give it a BI RADS 4 and biopsy.

3:04

For masses, as I showed that kind of similar to mammogram and ultrasound

3:10

when there is an oval or round circumscribed mass on a baseline MRI, it's

3:17

reasonable to give that a BI RADS 3 and follow.

3:21

Again, we really want to be careful looking for any changes in size

3:25

and have a low threshold to change that to a BI RADS 4 and

3:30

do a biopsy. And non mass enhancement continues to be a really challenging

3:37

topic. There's very limited data on this, but there is some small studies

3:43

and there's also some expert opinion that suggests that focal regional homogenous

3:50

non mass enhancement without associated T2 hyperintensity may be appropriate

3:56

for a BI RADS 3 assessment. So I did show an example of

3:59

that, but I just want to emphasize that there's not really robust data

4:02

to support this. And we'll really need to continue following the literature

4:07

and studying this topic to clarify which cases of non mass enhancement we

4:12

can safely give a BI RADS 3 to

4:17

and follow rather than biopsy and which cases we can consider to be

4:22

just part of the normal background enhancement and give a BI RADS 2.