While breast imaging techniques can find suspicious areas in your breast that may be cancer, they can’t tell for sure if cancer is present. A breast biopsy is needed to confirm a diagnosis of cancer.
Aside from skin cancer, breast cancer is the most common cancer affecting women in the United States. The
Breast imaging is a vital part of breast cancer screening, diagnosis, and staging. However, different imaging tests can show a radiologist different things.
The three most common breast imaging tests are:
In this article, we explore what each of these imaging tests of the breast can show as well as the next steps after these tests.
In this article, we talk about what radiologists can determine from mammograms, ultrasounds, and other breast imaging scanning techniques. Throughout this article, we use the terms “women” or “female” for people assigned female at birth.
It’s important to note that not everyone assigned female at birth identifies with the label “female.” However, at times we use “woman” or “female” to reflect the language in a study or statistic or to make sure people can find this article with the terms they search.
When possible, we aim to be inclusive and create content that reflects the diversity of our readers.
A mammogram is an imaging test that takes X-rays of your breast from various angles. It can be used both for breast cancer screening and for diagnosis.
In a mammogram, one of your breasts is compressed by plastic plates, which aids in getting a better picture of your breast tissue. X-rays of the breast are then taken at different angles. The process is repeated with your other breast.
When a radiologist examines the mammogram images, they can see several things that can inform them about whether or not cancer may be present:
- Masses:A mass is an abnormal area of breast tissue that often appears as a white patch on a mammogram. Masses can be:
- cysts, which are fluid-filled sacs in the breast
- fibroadenomas or other types of noncancerous breast tumors
- a cancerous breast tumor
- Breast density: Breast density is how much fibroglandular tissue versus fatty tissue is in your breast. Dense breast tissue also appears white on a mammogram and can also make it harder to see cancer in the image.
- Calcifications: Calcifications are calcium deposits that show up as bright white areas. Small clusters of calcifications called microcalcifications may mean that cancer is present, especially if they’re located close to a mass.
- Asymmetries: An asymmetry is an area of breast tissue that appears different from the pattern of breast tissue in the other breast. It typically shows up as a white area on a mammogram.
- Distortions: These are when breast tissue appears distorted in some way. They can be due to how the breast was positioned for the mammogram or to a previous injury or surgery to the breast. In some cases, they may be a sign of cancer.
While a mammogram can give a radiologist a lot of information about your breast tissue, it can’t tell them for sure if you have cancer. Other tests, including additional imaging tests, are necessary to diagnose breast cancer.
A breast ultrasound uses sound waves to create images of the breast. The sound waves are produced by a probe that’s moved across the surface of your breast. A special gel spread onto your skin helps the sound waves to travel better.
This type of imaging is used to help visualize things that are harder to see on a mammogram, especially breast masses. For example, a breast ultrasound can help a radiologist to differentiate between a fluid-filled cyst and a solid mass.
Having a breast ultrasound can also be more helpful for women with dense breasts. This is because potentially cancerous breast changes are harder to see in a mammogram due to the density of the breast tissue.
There are some things that an ultrasound can’t detect, particularly calcifications. Additionally, it can’t tell the radiologist if a solid mass is cancerous or not. Additional testing is needed for that.
Breast MRI uses a combination of magnets and radio waves to make cross-sectional images of your breast. It typically involves the injection of a special dye into a vein in your arm. This makes potentially cancerous areas easier to see.
Because it can create detailed images of soft tissues that are hard to see or are missed with other breast imaging techniques, breast MRI may be used to check an area of concern when mammogram or breast ultrasound results are unclear.
While MRI may be able to distinguish between typical and cancerous breast tissue better than other imaging types, breast MRI can still return a false-positive result. This is an area that looks like cancer but turns out not to be after a biopsy.
Additionally, like ultrasound, breast MRI can’t detect calcifications or tell if a solid mass is cancer or not.
There are also other uses for breast MRI. It may be used as a part of screening along with a mammogram in some people at a high risk of breast cancer and can also help determine the extent (stage) of cancer after a breast cancer diagnosis.
While breast imaging techniques can find suspicious areas that may be cancer, they can’t tell for sure if cancer is present. In order to do that, a breast biopsy is needed.
A biopsy collects a sample of tissue from the area. This sample can then be examined under a microscope for signs of cancer.
A breast biopsy is often done using a hollow needle to remove the tissue sample. Your breast will be numbed using a local anesthetic, so while you may feel some pressure, you won’t feel pain. Imaging is used to guide the needle. Techniques include:
- mammogram (stereotactic biopsy)
- breast ultrasound
- breast MRI
Additional tests after a biopsy
If cancer is detected in the biopsy sample, additional tests are done to determine the type and stage of the breast cancer. These can include:
- tests on the tissue sample to look for:
- estrogen and progesterone hormone receptors
- specific genetic changes
- lymph node biopsy to see if cancer has spread to the lymph nodes
- additional imaging to find out if the cancer has spread to more distant parts of the body, including:
If I feel a lump in my breast, should I have a biopsy or an imaging test?
If you have a concerning lump in your breast, imaging tests are done first. If imaging is inconclusive or suggestive of breast cancer, a biopsy will then be ordered.
Is one type of imaging test better than another?
Each breast imaging method has its benefits and drawbacks. Which type of imaging is used depends on your individual situation, such as your breast density and the purpose of the imaging (screening, diagnosis, or staging).
Is a 3D mammogram more accurate than a 2D one?
Generally speaking, there are two types of mammograms. A 2D mammogram makes a two-dimensional image of your breast, while a 3D mammogram uses several images of your breast to create a 3D image.
A 2019 study in women ages 65 and older found that 3D mammograms were more specific and led to a lower false-positive rate than 2D mammograms.
What type of imaging test is best if you have dense breasts?
Compared with other types of breast imaging, mammograms are generally more difficult to read in people with dense breasts.
If you have dense breasts, be sure to ask a doctor about what type of breast imaging is recommended for you. It’s possible that they may recommend that you receive a breast ultrasound on the same day as your mammogram.
Can imaging tests detect cancer if I have breast implants?
Yes. However, breast implants can make it harder to detect cancer on a mammogram, the most commonly used form of breast cancer imaging.
If you have breast implants, be sure to tell the technician before having your mammogram. Extra images are taken using a special technique that can help the radiologist get a better look at your breast tissue.
There are many different types of breast imaging. Each different type of imaging can tell a radiologist different things.
Mammograms can give a lot of information about breast tissue, including whether a potentially cancerous mass is present. However, they can also be difficult to read in people with dense breast tissue.
Breast ultrasound and MRI can help to evaluate things that are unclear in a mammogram. This includes whether or not a mass is a fluid-filled cyst or a solid mass. However, neither technique can detect calcifications.
The only way to tell if a suspicious area is cancer or not is to have a breast biopsy. However, the first step in breast cancer detection and diagnosis is imaging. Be sure to talk with a doctor about what type of breast imaging is right for you.