0:01

Okay, we're gonna talk about mammographic fat containing lesions. DBT is

0:07

helpful in fat containing lesions because it may reveal the presence of

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fat within a finding which is not apparent on 2D imaging related to

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the overlying dense tissue. However, the presence of fat within lesions

0:19

does not necessarily make the lesion invariably benign. The lesions margins

0:25

also need to be evaluated. DBT allows the assessment of lesion internal

0:28

components and margins and to recognize the, typically, benign encapsulated

0:34

mass. So having that circumscribed margin around a fat containing a mass

0:39

is critical for interpretation. If fat containing and encapsulated, then

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a benign assessment is warranted. Otherwise, additional imaging or evaluation

0:47

or potentially a biopsy is needed. Example, encapsulated fat containing

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masses include lipoma, hematoma, fat necrosis, and galactocele. In terms

0:59

of lipoma, it's typically superficial or intramuscular. It may manifest

1:02

at physical exam and patients may have multiple additional lipomas. This

1:07

can be helpful in your diagnostic setting in the sense where if you're

1:10

evaluating a fat containing lesion, potentially go to ultrasound and you

1:14

talk to the patient and they say, oh yes, I have multiple of

1:17

these all over my body, you can be even more confident that it

1:19

is the imaging finding you're seeing it's probably a lipoma. Typically,

1:24

benign fatty neoplasm, which does not require further imaging, evaluation,

1:28

or follow up, it may be difficult to identify on mammographic exams,

1:32

but it's more classically seen on ultrasound exams. Hematomas are

1:40

also benign circumscribed masses. They contain a very amount of normal appearing

1:45

fibroglandular tissue as well as fat. And this falls into the classic teaching

1:50

of the breast within a breast appearance. It demonstrates a capsule or pseudo

1:55

capsule at mammography. It's usually round or oval, an overall shape.

1:59

Contains a variable normal breast tissue components, fat, glandular tissue

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calcifications. Because they have these glandular components, malignancies

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may develop within a hematoma as well and so they need to be

2:13

closely evaluated as well. Fatty necrosis, of course, we see in a lot

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of screening and diagnostic exams. It has a variable mammographic appearance

2:22

based on the phase of development. You can see an oval or round mass,

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possibly with a fluid level. You may see an overall round fat containing

2:30

mass with associated rim calcification, sometimes called an oil or lipid

2:35

cyst, which is what's demonstrated in this image.

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And additional associated imaging findings of fat necrosis are also possible.

2:42

You may see loose and centered, coarse or dystrophic calcifications or distortion,

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rim like appearance, all those demonstrate are related to fat necrosis.

2:51

Galactocele is obviously most commonly arise in a lactating female secondary

2:56

to entrapped milk arising from a clogged duct. This can be quite large,

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quite numerous, or it can be solitary and small. The imaging appearance

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really depends on the amount of fat and milk contained within.

3:07

You usually see a round or oval circumscribed mass, you can see a

3:11

possible fat fluid level, which is pathognomonic and therefore doesn't need

3:14

any further workup. An ultrasound, of course, is helpful for evaluating

3:18

further internal contents and to distinguish it from something that might

3:21

be like a solid and cystic mass, which would require further evaluation

3:26

of biopsy. Non encapsulated fat containing masses, of course, also exist.

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They can be circumscribed, something like a phyllodes tumor or a papillary

3:35

mucinous or high grade invasive ductal carcinoma can also be seen or potentially

3:39

metastatic disease. Speculated masses and distortion can contain some fat,

3:44

like a radius scar, complex sclerosing lesions, sometimes called that dark

3:48

star appearance. Invasive ductal carcinomas could also present that way

3:52

as well. So the bottom line is that non encapsulated masses or masses

3:56

don't have that thin circumscribed margin and they demonstrate any suspicious

4:01

features should be recommended for biopsy. So if you see any of those

4:04

components, you really need to do some more work to figure out what

4:06

exactly that is. In this case here, we see this mass in the

4:11

left breast at approximately two o'clock position, middle depth, and we

4:15

can see some internal components which have some fat within it.

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So, for example, here and here, but clearly this mass does not have

4:22

a circumscribed margin. This is at least indistinct, possibly obscured.

4:27

You also sort of wonder about some of this density going this direction

4:30

here. And clearly this warrants some further evaluation. That mass was subsequently

4:34

biopsied and was an invasive ductal carcinoma.