A mammogram is the most effective test for detecting early breast cancer. It is a special X-ray of the breast that can reveal tumors that are often too small to be felt or noticed on a physical examination. It can also show other changes in the breast that doctors believe may suggest breast cancer.
Having regular screening mammograms can detect breast cancers when they are small and easier to treat.
A screening mammogram is appropriate for cisgender women, trans men who have not had a mastectomy or top surgery, and trans women, non-binary, and gender nonconforming people who have initiated estrogen as part of gender affirming care.
When should I have a mammogram?
To determine when and how to screen for breast cancer, you should have a discussion with your health care team about your risk of developing breast cancer, your preferences, your personal and family history, and your team’s recommendations.
The American Cancer Society (ACS), American College of Radiology (ACR), the National Comprehensive Cancer Network (NCCN), and U.S. Preventive Services Task Force (USPSTF) offer useful guidelines about when to start having regular mammograms for early detection of breast cancer.
The ACS recommendations state that:
- Women ages 40-44 have the option to start annual mammograms
- Women ages 45-54 who are at average risk of breast cancer should have yearly mammograms
- Women ages 55 and older can continue annual mammograms or switch to every other year as long as they are in good health and have a life expectancy of ten years.
The ACR guidelines and NCCN guidelines recommend annual screening mammograms beginning at age 40 and continuing as long as you are in good health with a life expectancy of at least five to seven years.
In 2024, the USPTF updated their guidelines to be more aligned with the American Cancer Society, with recommendations to initiate breast cancer screening at age 40 based on data suggesting that earlier screening would identify more breast cancer cases, particularly among younger Black women. The guidelines recommend screening every other year through age 74. After this age, there aren’t clear guidelines on screening, and the decision should be made by individuals and their clinicians.
Breast cancer screening is also important for some LBGTQ+ people, such as trans men who have not had a mastectomy or top surgery, who should follow screening recommendations for cis women. Trans women, non-binary, and gender nonconforming people who have initiated estrogen as part of gender affirming care might develop breast tissue. They should be screened for breast cancer after 5 years on hormones starting from age 40-45.
Of note, breast Magnetic Resonance Imaging (MRI) is not yet a part of standard breast cancer screening, but it may be included in the screening program for some people, depending on risk factors and family history.
“Although the guidelines from these organizations continue to shift over time and will continue to do so, it’s important to remember that one thing has never changed (nor will likely change): Patients should talk with their clinicians about what works best for them when it comes to screening for breast cancer, with an individualized decision that incorporates one’s anticipated risk of breast cancer and preferences,” says Rachel A. Freedman, MD, MPH, a medical oncologist in the Susan F. Smith Center for Women’s Cancers at Dana-Farber and medical director of the Program for Older Adults with Breast Cancer (OABC).
Who is at higher risk of breast cancer?
You may be at an increased risk of developing breast cancer if you:
- Have cancer-susceptibility genes such as BRCA1 and BRCA2 or other inherited gene abnormalities
- Have had certain benign breast conditions
- Have a family history of breast cancer
- Had had chest irradiation as prior treatment
Individuals with gene mutations that predispose them to develop breast cancer typically begin regular screening at an early age, which usually involves a breast Magnetic Resonance Imaging (MRI) test in addition to mammography. In general, adults at increased risk may even begin screening earlier than age 40. Be sure to talk to your doctor about what might be right for you.
Learn more: Take Dana-Farber’s AssessYourRisk Quiz to learn more about your personal risk of breast and ovarian cancer.
Where can I get a mammogram?
Your doctor can help you schedule a mammogram. If you have health insurance, breast cancer screening that falls within accepted guidelines should be free of charge.
Dana-Farber’s Mammography Van provides mammograms and breast health education in the Boston area for people who might not have easy access to screening. Preregistration is required. Check their upcoming calendar and contact the mammography van office at 617-632-1974 or via email to make an appointment.
Free screening programs are also available across the country.
At what age can I safely stop having a regular mammogram?
There currently isn’t enough evidence to claim that mammograms benefit patients later in life, particularly if other medical conditions are likely to limit their life expectancy. Life expectancy can be very hard to estimate, but in general, if a person’s overall health is poor, the benefits of mammography in later years may be outweighed by the risks that may come with mammograms — false positives (having additional tests when there is no cancer), discomfort, anxiety, and over-treatment, in which an individual would undergo treatment for a cancer that would not have affected longevity.
Adults of all ages and genders should talk with their health care team on what might be right for them, because these decisions should be very individualized.
“The decision on when and how to start and stop having mammograms, regardless of age, should be one that is individualized, based on a patient’s concerns, risks, and other health priorities,” says Freedman. “However, as we age, the benefits will lessen and there will be a ‘right’ time to stop this testing.”