Breast Imaging: Mammography

00:01 Welcome.

00:02 In this relatively brief talk, we're going to cover the aspects of mammography that you need to understand as a medical student.

00:08 Mammography is just the radiologic imaging to evaluate breast lesions.

00:13 It may occur at different frequencies depending on the indication.

00:17 All women should have at least one mammogram after the age of 40.

00:24 And then the frequency thereafter is going to be vary depending on the findings and other risk considerations.

00:30 High risk individuals, someone who has a first degree relative, or a family history of breast cancer should be evaluated by the age of 30, and then probably annually.

00:41 If there's a palpable mass in any woman over the age of 30, that probably merits a mammography.

00:47 And for the evaluation of breast pain or tenderness, nipple discharge, skin and nipple retraction or changes, all those merit a mammogram.

00:58 There are kind of standard views.

01:00 So we're showing the typical procedure with a cranial caudal view with the breast being compressed between plates to distribute the tissue as much as possible so that we get good radiation penetration.

01:12 The medial lateral oblique view or the MLO view is a better view for the superior lateral quadrant, the upper outer quadrant of the breast, that's actually where the majority of breast cancers will occur.

01:24 That's where the majority of breast tissue is because the breast actually extends up into the axilla.

01:30 So normal breast is composed of parenchyma, ducts and lobules as well as mesenchymal or connective tissue, and fat, and vessels.

01:41 And so when we look at the normal breast compressed between the radiographic plates, we're going to see relative areas of clarity, that's going to be mostly fatty tissue, and then where we see white, that's going to represent the parenchyma, the epithelium, as well as the vasculature and the connective tissue.

01:59 It makes a difference whether you're looking at a young woman who has relatively dense breasts with a lot of parenchyma, and greater mesenchymal elements, such as fibrous connective tissue, versus an older woman, who will have mostly fat, there's been regression of a lot of the epithelium.

02:17 So in a young woman, there is going to be dense parenchyma.

02:22 And clearly, small tumors can hide better within the tissue.

02:29 On the other hand, in the geriatric patient, it's very radiolucent because there isn't much in the way of parenchyma and the other stroma elements, and you can see through it quite easily, much harder for a tumor to hide in there.

02:44 Characteristic findings on a mammogram.

02:46 So a normal mammogram will have that kind of distribution mesenchymal elements, fat, parenchyma.

02:55 Benign cysts, which are going to be more common than malignancy are going to be typically smooth, uniform, rounded, things that can be mobile within the breast.

03:08 Breast calcifications will occur frequently either with fibrocystic change or can occur with malignancy.

03:14 So the mammographer will want to be very careful in evaluating those and looking at areas of microcalcifications.

03:21 It's about 50/50 between benign things and malignant things when they're little areas of calcium.

03:27 And then breast cancer tends to be an irregular radio dense, kind of stellate looking crab like appearance lesion, which will radiate again into the associated tissue.

03:41 Once we've identified something on mammography.

03:43 The mammographer may put a needle or a wire in to show the surgeon exactly where to do a biopsy or to actually do an excision.

03:55 We want to evaluate abnormal findings clearly.

03:58 If it seems like it's a uniform round structure, then an ultrasound may be sufficient to just demonstrate that it's a cyst.

04:05 We can also do MRI and CT.

04:08 For lesions that are amenable we may put in a long needle and just aspirate out to make sure that the cells that are in there are benign.

04:16 Or we may do a biopsy.

04:18 And what's been shown is benign fibrocystic change.

04:22 And again, I will refer you to another talk elsewhere within the breast pathology section of the Lecturio slides for fibrocystic change, or infiltrating ductal carcinoma, which can be something else that you would see on biopsy, and we'll talk about breast cancer in a separate set of talks.

04:39 With that, I think you've got the fundamentals of thinking about mammography, how to evaluate it, and how to explain to your patients what's going on.