Breast Cancer Screening

Breast cancer screening looks for cancer before symptoms develop. Finding breast cancer at an earlier stage can make it easier to treat and may improve the chances of successful treatment. The right screening plan depends on your age and individual breast cancer risk.

Mammograms

A mammogram is an X-ray of the breast and is the primary screening test used to detect breast cancer. Mammograms can identify breast cancers that are too small to see or feel. They may also detect tiny calcium deposits called calcifications, which can sometimes be an early sign of breast cancer. Most modern screening centers use digital mammography, and many use 3D mammography, also called digital breast tomosynthesis. This creates multiple images of the breast from different angles and can help doctors see abnormalities more clearly.

When should breast cancer screening begin?

For women at average risk, screening recommendations vary somewhat among medical organizations. The U.S. Preventive Services Task Force (USPSTF) recommends that women ages 40 through 74 receive a mammogram every two years. Other organizations recommend annual screening beginning at age 40 or allow women to choose between annual and every-other-year screening depending on age and individual preferences. Because recommendations can differ, talk with your healthcare provider about when you should begin screening and how often you should have a mammogram.

What does “average risk” mean?

You may be considered at average risk if you do not have factors that substantially increase your chance of developing breast cancer. People at increased or high risk may need a different screening plan. Factors that may increase your risk include:

• A strong family history of breast cancer

• A known inherited genetic variant associated with breast cancer, such as BRCA1 or BRCA2

• A first-degree relative with a high-risk genetic variant

• Previous radiation therapy to the chest at a young age

• Certain high-risk breast conditions found on a biopsy

• A calculated lifetime breast cancer risk of approximately 20% or greater

If any of these apply to you, ask your healthcare provider whether you should begin screening earlier or receive additional imaging.

Breast MRI

A breast MRI uses magnets and contrast material rather than X-rays to create detailed images of the breast. MRI is not generally used as a replacement for mammography. Instead, it may be used in addition to mammograms for people at high risk of breast cancer. For example, annual breast MRI may be recommended for some people with:

• BRCA1 or BRCA2 variants

• Certain other inherited cancer syndromes

• A very strong family history

• A calculated lifetime breast cancer risk of approximately 20% to 25% or greater

• A history of radiation therapy to the chest at a young age

Your healthcare provider can help determine whether MRI screening is appropriate for you.

What if I have dense breasts?

Breasts contain a combination of fatty tissue, connective tissue, and glandular tissue. When there is more fibrous and glandular tissue relative to fatty tissue, the breasts are considered dense. Breast density is important for two reasons:

• Dense breast tissue can make some cancers harder to see on a mammogram.

• Dense breasts are themselves associated with an increased risk of breast cancer.

Your mammogram report should tell you whether you have dense breasts.

Depending on your overall risk, your healthcare provider may discuss whether additional imaging, such as breast MRI or ultrasound, could be helpful. Supplemental screening is not automatically necessary for everyone with dense breasts, so this decision should be individualized.

Breast ultrasound

A breast ultrasound uses sound waves to create images of breast tissue. Ultrasound is often used to evaluate an abnormality found during a mammogram or physical examination. It can help determine whether a breast lump is solid or filled with fluid. In some situations, ultrasound may also be considered as supplemental screening, particularly for people with dense breasts. However, ultrasound generally does not replace mammography for routine breast cancer screening.

Are clinical breast exams recommended?

A clinical breast exam is an examination performed by a healthcare professional to check the breasts and surrounding areas for lumps or other abnormalities. Recommendations regarding routine clinical breast exams vary. They are not considered a substitute for mammography. Your healthcare provider may still examine your breasts as part of your overall care or evaluate a specific breast concern.

Know what is normal for your breasts

Formal monthly breast self-exams are no longer universally recommended as a screening test for people at average risk. However, it is still important to be familiar with how your breasts normally look and feel. Contact your healthcare provider if you notice a new or unusual change, including:

• A new breast or underarm lump

• Thickening or swelling of part of the breast

• Changes in breast size or shape

• Skin dimpling, puckering, or irritation

• Redness, scaling, or other skin changes

• A nipple that becomes newly inverted

• Nipple discharge, particularly bloody discharge

• Persistent breast or nipple pain

• Swelling or a lump in the underarm or near the collarbone

Do not wait for your next screening mammogram if you develop a new breast symptom. Screening is intended for people without symptoms. New breast changes should be evaluated by a healthcare professional.

What happens if a mammogram finds something?

An abnormal mammogram does not automatically mean you have breast cancer. You may be asked to return for additional testing, which can include:

• Additional mammogram images

• Diagnostic mammography

• Breast ultrasound

• Breast MRI

• A breast biopsy

Many findings turn out to be benign, or noncancerous. If imaging shows an area that could potentially be cancer, a biopsy may be needed to remove a small tissue sample for examination.

Screening for people at high risk

If you are at high risk for breast cancer, your screening plan may be different from routine screening. Depending on your individual risk, your healthcare team may recommend:

• Starting screening at a younger age

• Having mammograms every year

• Adding annual breast MRI

• Genetic counseling or genetic testing

• Regular visits with a breast specialist or high-risk clinic

Risk assessment can take into account your age, family history, breast density, reproductive history, previous breast biopsies, genetic test results, and other factors.

The bottom line

Breast cancer screening is one of the most important tools for finding breast cancer early. For many women at average risk, mammography begins at age 40. People at increased risk may need to start earlier or receive additional screening, such as breast MRI. Your screening plan should be based on your age, personal history, family history, breast density, genetic risk, and preferences.

Talk with your healthcare provider about your breast cancer risk and which screening schedule is right for you.