Breast health is an important part of preventive care throughout life. Regular screening, awareness of changes in your breasts, and understanding your personal risk factors can help with the early detection of breast cancer and other breast conditions. This page provides guidance about breast cancer screening, mammogram results, breast density, breast cancer risk, and common breast concerns, along with trusted resources to help you better understand your breast health.
Understanding the basic structure of the breast can be helpful when describing a new symptom or making sense of breast imaging. Breast tissue includes lobules, ducts, fatty and fibrous tissue, lymph nodes, and the nipple and areola.
You don't need to perform a formal breast self-exam on a specific schedule. Instead, it's helpful to be familiar with how your breasts normally look and feel so you can recognize changes. Contact your healthcare provider if you notice a new lump or area of thickening, persistent focal breast pain, a new change in breast size or shape, skin dimpling or other skin changes, new nipple changes, or spontaneous nipple discharge, particularly if it is bloody or clear.
Mammography is the primary screening test used to detect breast cancer before symptoms develop. For most women at average risk, breast cancer screening begins around age 40.
Recommendations about how often to have a mammogram vary somewhat between medical organizations. Depending on your age, personal risk factors, and preferences, screening may be recommended every 1–2 years.
Some people have a higher-than-average risk of breast cancer and may benefit from earlier screening, breast MRI, or a different screening schedule. Your family history, breast density, previous breast biopsies, genetic factors, and other medical history can help determine which screening plan is appropriate for you.
Mammography and Other Screening Tests for Breast Problems (ACOG)
Breast Cancer Screening & Baseline Mammograms (Menopause Society, video)
During a mammogram, each breast is positioned between two plates and briefly compressed while X-ray images are taken. The compression can feel uncomfortable, but each image only takes a few seconds. Most screening mammograms today use 3D mammography (digital breast tomosynthesis), which creates multiple images of the breast from different angles.
Mammograms do use a small amount of radiation, but the amount is very low. A typical screening mammogram exposes you to about the same amount of radiation that you naturally receive from your environment over 1–2 months.
For women who are eligible for breast cancer screening, the benefit of detecting breast cancer early far outweighs the very small potential risk from radiation exposure. The breast compression used during a mammogram also does not cause breast cancer or cause cancer to spread.
Mammography remains the recommended primary imaging test for routine breast cancer screening. Other types of breast imaging can be helpful in certain situations, but they should not be used as a substitute for a recommended screening mammogram.
Breast ultrasound is very useful for evaluating a specific breast lump or an abnormality found on a mammogram. In some women, particularly those with dense breast tissue or other risk factors, ultrasound may also be considered as supplemental screening in addition to mammography.
Commercial whole-breast ultrasound screening services, such as HERScan, may offer ultrasound without a physician referral. While ultrasound does not use radiation, it does not replace mammography for routine breast cancer screening.
Thermography also does not use radiation, but it has not been shown to be an effective standalone breast cancer screening test and should not replace mammography.
If you're interested in supplemental breast screening because of dense breast tissue, family history, or other concerns, talk with your healthcare provider about which imaging tests are appropriate for your individual risk.
Mammogram reports use a standardized system called BI-RADS (Breast Imaging Reporting and Data System) to describe the radiologist's findings and recommend what should happen next. BI-RADS categories range from 0–6 and can also be used for breast ultrasound and MRI results.
An abnormal mammogram result does not necessarily mean breast cancer. Many findings require additional imaging simply so the radiologist can get a better look or confirm that an area is benign.
Your mammogram report will usually include a BI-RADS score, which is a standardized way for the radiologist to summarize what they see and what, if anything, should happen next.
BI-RADS 0: We need a little more information
This is a very common result after a screening mammogram. It simply means the radiologist needs additional images or previous mammograms for comparison before giving you a final result. You may be asked to return for a diagnostic mammogram and/or breast ultrasound. Being called back does not mean that you have breast cancer.
BI-RADS 1: Everything looks normal
Your mammogram did not show anything concerning. You can return to your usual breast cancer screening schedule.
BI-RADS 2: We see something, but it looks benign
Your mammogram showed a finding that the radiologist recognizes as noncancerous, such as certain cysts or calcifications. No additional evaluation is needed, and you can continue your usual screening schedule.
BI-RADS 3: This looks very likely to be benign, but we'd like to keep an eye on it
The radiologist sees something that is very unlikely to be cancer, but would like to make sure it stays stable over time. You'll usually be asked to return for repeat imaging, often in about 6 months. Fewer than 2% of BI-RADS 3 findings are ultimately diagnosed as cancer.
BI-RADS 4: We should take a closer look
The radiologist sees an area that cannot confidently be called benign based on imaging alone. A breast biopsy is usually recommended so the tissue can be examined more closely. There is a wide range of findings included in BI-RADS 4, and a recommendation for biopsy does not mean that you have breast cancer.
BI-RADS 5: This finding is more concerning
The imaging has features that are more strongly associated with breast cancer. A biopsy is recommended to determine exactly what the area represents. Imaging alone still cannot make the final diagnosis, which is why the biopsy is important.
→ Learn more about what happens after an abnormal mammogram.
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If your mammogram shows dense breast tissue (category C or D), you may have the option of additional breast cancer screening in addition to your yearly mammogram. Supplemental screening is optional, and there are several different options depending on your preferences, breast density, individual risk factors, and insurance coverage.
→ Learn more about Dense Breast Tissue & Supplemental Screening
Breast cancer risk is influenced by many factors, and family history is only one part of the picture. Age, breast density, reproductive history, previous breast biopsies, certain medical conditions, family history, and inherited genetic factors can all contribute to your overall risk.
Risk assessment tools can combine these factors to estimate your chance of developing breast cancer over time. These estimates can help determine whether you may benefit from a different breast cancer screening plan.
You may see a lifetime breast cancer risk percentage listed on your mammogram report or calculated during a healthcare visit. This number estimates your chance of developing breast cancer over your lifetime based on the information entered into a breast cancer risk model.
One commonly used model is the Tyrer-Cuzick (IBIS) model, which considers factors such as your age, family history, reproductive history, breast density, and certain previous breast biopsy findings.
A calculated lifetime risk of 20% or greater is commonly considered high risk and may change breast cancer screening recommendations, including consideration of annual breast MRI in addition to mammography.
Estimate Your Breast Cancer Risk:
Tyrer-Cuzick Breast Cancer Risk Assessment Calculator (MagView)
The Tyrer-Cuzick Model: Understanding the Assessment and Your Breast Cancer Risk (National Breast Cancer Foundation)
Risk calculators provide an estimate rather than a prediction, and the result is only as accurate as the information entered. If your result is elevated or you're unsure how to interpret it, discuss it with your healthcare provider.
If your breast cancer risk assessment shows that you are at higher-than-average risk, you may benefit from a more individualized screening plan. Depending on your risk factors, this may include earlier or more frequent mammograms, breast MRI, or other strategies to help reduce your risk.
Novant Health's High Risk Breast Clinic provides individualized breast cancer risk assessment and recommendations for patients at increased risk.
Some family histories can suggest an inherited predisposition to breast, ovarian, or other cancers. This is different from your overall breast cancer risk assessment and may be a reason to consider genetic counseling or genetic testing.
→ Learn more about Hereditary Cancer Risk
There is no way to completely prevent breast cancer, and many important risk factors, including age, genetics, family history, and breast density, are not things you can change. However, there are steps that may help lower your risk.
Some of the most important modifiable factors include:
Limiting alcohol, since breast cancer risk increases with alcohol consumption
Regular physical activity
Maintaining a healthy weight, particularly after menopause
Avoiding tobacco use
Considering the potential benefits and risks of menopausal hormone therapy based on your individual circumstances
For patients at higher-than-average risk, additional risk-reduction strategies may sometimes be appropriate, including medications that lower breast cancer risk or, much less commonly, preventive surgery. These decisions are individualized and are typically discussed with a breast specialist or high-risk breast clinic.
Breast pain, breast lumps and cysts, nipple discharge, and many other breast changes are common and are often caused by noncancerous conditions.
→ Learn more about Benign Breast Conditions