Many women wonder whether breast ultrasound or mammogram is the better choice for breast cancer screening. The truth is, these tests aren’t meant to replace one another—they work best together. When combined, mammograms and breast ultrasounds can increase cancer detection rates by up to 96% in women with dense breast tissue, offering a more complete picture of breast health. Using both tools provides a comprehensive approach to early detection.
Why Is Comprehensive Screening for Breast Cancer So Important?
The reason is that it prevents deaths from breast cancer. Between 1975 and 2019, breast cancer deaths dropped 58%. This was due to a combination of screening mammography and improvements in treatment.
Today, the average woman has about a 12% lifetime risk of developing breast cancer—roughly one in eight women. Excluding skin cancer, breast cancer is the most common type of cancer in women today. One out of every three cancers diagnosed today is breast cancer. This is why comprehensive screening is so critical.
Screening Tools: More than Just Mammograms
When it comes to breast cancer screening, most women immediately picture mammograms. But the truth is that there isn’t just one tool that does it all. Mammograms and ultrasounds work in different ways—and both can be powerful in detecting tumors early. Often, they are combined to increase breast cancer detection rates.
One of the essential breast cancer facts every woman should know is that there isn't just one single tool for detecting tumors. Breast ultrasound and mammography are two different methods for breast cancer screening.
Your family history, individual risk factors, and past experiences with mammograms can all help to determine the best test for you.
Breast Ultrasound vs. Mammogram: What's the Difference Between the Two?
Here’s a comparison and why your healthcare provider might recommend one over the other.
How Mammography Works
- How it works: Mammograms are breast screenings that use X-ray imaging to identify changes in breast tissue. These can identify changes that may indicate growths or early signs of breast cancer. These changes may not be caught with self-detection, MRIs, or ultrasound.
During a mammogram, breasts are flattened between two surfaces to thin out tissue and capture digital imagery. The images are then reviewed by a specialized doctor called a radiologist. If an area of concern is identified, a diagnostic ultrasound may be necessary.
- Strengths: Mammograms are used as screening tools and can detect early calcifications and subtle changes not visible by touch or ultrasound. The role of a screening tool (mammogram) is to detect risk factors or potential cancerous growths early on before progression (while they are still asymptomatic).
- Limitations: Less effective in women with dense breast tissue. In addition, mammograms do not provide diagnostic certainty.
How Breast Ultrasound Works
Types:
- Diagnostic ultrasound uses sound wave technology to obtain an image of the breast's internal structure. This image is used to pinpoint if breast lumps are solid or fluid-filled masses. The role of a diagnostic ultrasound is to confirm or rule out cancer after something abnormal is detected during screening. Being referred for a diagnostic ultrasound does not necessarily mean that a patient has breast cancer. However, it does mean that the results of screening need to be clarified.
- Screening ultrasounds are used proactively, particularly for high-risk individuals or those with dense breasts where mammograms may be less effective, to supplement routine screening and catch cancers that might otherwise be missed.
- Strengths: These screenings can distinguish fluid-filled cysts (benign) from solid masses (which may need further evaluation). In women with dense breast tissue (where mammograms can miss abnormalities), ultrasound can often detect lumps, cysts, or tumors more effectively. Ultrasound is painless, noninvasive, and fast. It is also a radiation-free option.
- Limitations: Unlike mammography, ultrasound cannot reliably detect microcalcifications.
Mammogram + a screening ultrasound may be the best screening option.
When Is It Time to Book a Breast Ultrasound vs Mammogram?
Mammograms are routine. They should be a part of the routine age-based or risk-based health screening that you have with your care provider. The American Cancer Society recommends the following:
- Women between the ages of 40 and 45 are screened annually for breast cancer.
- Women ages 55 and over can choose to either continue with annual mammograms or switch to every other year.
If findings on your mammogram require clarification, your healthcare provider may order a diagnostic breast ultrasound. However, you can order a screening breast ultrasound (without a doctor’s referral) at any age. Here are some instances where you might also want to have a breast ultrasound:
- You have dense breast tissue that is difficult to see on mammogram imaging.
- You're experiencing repeated localized breast pain in a single spot.
- You have felt a lump in a certain area.
- You have a family history of breast cancer or have the BRCA mutation.
- You are younger than the standard age for a mammogram but want to be proactive about getting screened.
How Do You Know When a Breast Lump Is Concerning?
Breast lumps aren't uncommon. In many cases, lumps may be benign, fluid-filled masses that only require further monitoring. However, the development of a new lump or change to an existing lump must be addressed with a care provider.
What do breast lumps feel like? Common types include:
- Cysts: Breast cysts are fluid-filled sacs within the breast that are often benign. They can feel like "squishy" grapes or water-filled balloons. However, firmness can vary.
- Fibroadenomas: These are painless, round lumps that often feel like firm, rubbery peas within the breast. These benign lumps are made of glandular and fibrous breast tissue.
- Papillomas: Papillomas are benign tumors that form in the breast milk ducts. They present as small, painless lumps that can be felt underneath the nipple. Some produce clear or bloody discharge.
- Malignant tumors: These often present as hard, marble-like lumps with asymmetry. While most are painless, some do cause pain or tenderness. There may also be swelling, skin changes, or discharge.
What Is the Importance of Combining a Mammogram and Ultrasound for Increased Detection?
Skipping straight to an ultrasound for a breast cancer diagnosis is not necessarily recommended for every woman. In certain situations, you may be a candidate who would benefit from a supplemental ultrasound, even if you have no signs of breast cancer.
Who Benefits From Receiving a Breast Ultrasound?
Here are some cases where a woman may be a candidate for both a screening mammogram and a screening ultrasound.
You Have Dense Breast Tissue
According to HerScan’s lead sonographer Heather Johnson “asymptomatic individuals with dense breast tissue may benefit from adding screening breast ultrasound to their breast health regimen.”
Roughly 50% of women have dense breast tissue. An ultrasound may be able to detect cancers that would remain hidden by thick breast tissue during an ordinary mammogram. On a mammogram, dense tissue appears similar to white cancerous tumors. As a result, it can be nearly impossible to distinguish a tumor from other tissue. A study found that the sensitivity of a mammogram drops from 85% to just 48% to 64% in women with dense breasts.
Johnson says, “Because no imaging modality is perfect, it can be helpful to combine both mammography and breast ultrasound in individuals with dense breast tissue.” She goes on to explain, “Mammography is excellent at identifying microcalcifications, even in the most dense tissue. The sensitivity of a mammogram identifying masses within dense tissue, however, is limited.”
You Have an Increased Genetic Risk
Ultrasound screening is also recommended whenever there's a genetic or family risk factor involved. For women with BRCA mutations or other risk factors, ultrasound offers an extra layer of reassurance.
You Are Having Symptoms
Johnson says “symptomatic individuals can benefit from ultrasound, but they are best served with a diagnostic breast ultrasound, not a screening breast ultrasound.”
How Does Breast Ultrasound Find Some Cancers That Mammography May Miss?
Johnson explains how this works: “The sound waves used in ultrasound and the x-rays in a mammogram do not act the same in dense tissue. When x-rays from a mammogram reach dense tissue, they stop and make the image look white. The same thing happens when x-rays from a mammogram reach a mass - they stop and show up white on the image.”
“Masses that appear white on an image can be very challenging, sometimes impossible to see when situated within dense tissue that also shows up white. The sound waves from an ultrasound, on the other hand, do not stop when they reach dense tissue. This means that we can see from the skin, all the way to the chest wall. That coupled with ultrasound's ability to characterize masses both within dense tissue (aka fibroglandular tissue) and fatty tissue make it a great complementary exam to mammography.”
How to Talk With Your Provider About Your Best Screening Plan
Johnson says that “everyone is unique. Talk to your provider to determine if you have dense breast tissue and if your unique situation could benefit from supplemental screening breast ultrasound.”
Why Choose HerScan for Breast Cancer Screening?
According to Johnson, HerScan is a “convenient, inexpensive option for breast screening ultrasound.”
At HerScan, we offer advanced mobile breast ultrasound screenings. They are compression-free, quick, and comfortable. Our ultrasound appointments generally last just 20 minutes.
After the test, the images are reviewed by board-certified radiologists. If you have dense breast tissue or an increased genetic risk, don’t wait; schedule your appointment today.
Early detection is everything in the fight against cancer. We encourage women to stay informed and take charge of their healthcare by adding a powerful Breast Ultrasound to their breast healthcare regimen. To schedule an appointment at your convenience, please click here.
