When a radiologist is reviewing your mammogram there are three things in particular they are looking for to exclude possible cancer: mass, architectural distortion, and suspicious calcifications. We will discuss each feature, but many of these things may only be detected when comparing to prior exams, which is why you should have ANNUAL mammograms.
As mentioned in my previous post, mammography is heavily regulated with the Breast Imaging-Reporting and Data System (BI-RADS) providing dedicated verbage for describing imaging findings on mammography. A suspicious soft tissue density is classified as an asymmetric density when seen on a single routine screening mammographic view (CC or MLO), a focal asymmetry when seen on both views and has concave margins, and a mass if seen on both views with convex margins. So, when you read or hear the words mass, does it make you think of cancer? For some reason it suggests that to me. In reality, and according to BI-RADS, the description of a mass could indicate a solid lesion but it also perfectly describes a simple cyst that is completely innocent. It is often the descriptors that indicate the degree of concern, particularly the margins. Are they circumscribed, smooth and well-defined suggesting a benign lesion or spiculated and irregular more suspicious of a malignant cancer.
Architectural distortion can be extremely subtle. Here is how I will describe it. As we said before, simplistically the breast is composed of fat and fibroglandular tissue. The glandular tissue makes milk, but the fibrous tissue provides the supporting network for the glands, ducts and fat tissue. It is this fibrous network that forms what would be like a perfect spider web with the center radiating toward the nipple. Now, if you have a tumor, or had surgery, a biopsy, or serious trauma, then that network can become disrupted. It is like a rain drop put a tear in the spider web. It no longer has that perfect appearance, but shows an area of architectural distortion in the web. The same thing happens to the breast. But instead of seeing a torn web pointing to wear the rain drop went through, we are looking for a cancer going through the normal fibrous connective tissue network in the breast. Cancers can distort the normal appearance of the breast on mammography. The ability to detect subtle architectural distortion catching cancers early is a tremendous strength and advantage of 3D breast tomosynthesis mammography.
Calcification occur in the breast for a myriad of reasons, mostly benign. Seriously, almost every breast has one calcification. They are exceedingly common, present as vascular calcifications, secretory calcifications, fat necrosis, and the hodge-podge term, dystrophic calcifications. So most of the time, your breast will have calcifications but they will be benign. But when tiny so-called microcalcifications are present clustered in groups with differing sizes and shapes it could suggest a cancer. This is just one of many different, subtle patterns calcifications may present which could suggest cancer to your radiologist. Mammography, particulary in relation to calcifications, is definitely a science and an art.
So don’t go thinking you can read your mammogram based on anything I have written here. It has taken me nearly a decade to have the confidence that is still occasionally humbled when reading mammography. Additionally, an intake form filled out by the patient to include personal, family and genetic history, if known, should be assessed concomitantly by the radiologist with each mammogram to aid in their review of the case.
Okay, last shout out for this post: get your ANNUAL mammogram. You will have to trust me. Identifiers were removed to protect patient confidentiality. I saw this patient last week. Unfortunately she skipped her annual mammogram. 2018 is on the left and 2016 on the right. It doesn’t take a radiologist to see this cancer. I told you. It does happen!