Mammography FAQ

A mammogram is an X-ray performed by a trained professional called a mammographer or breast technologist who properly positions and compresses the breasts (crucial for high-quality images) and checks the images immediately for quality. It is performed both as a screening test and as a diagnostic exam.

A screening mammogram is an exam used to detect early breast cancer in women experiencing no symptoms. Mammography plays a central part in early detection of breast cancers because it can show changes in the breast up to two years before you or your physician can feel them. Current guidelines recommend screening mammography every year beginning at age 40. In addition, women who have had breast cancer and those who are at increased risk due to a genetic history of breast cancer should seek expert medical advice about whether they should begin screening before age 40 and about the frequency of screening.

Diagnostic mammography is used to evaluate a patient with abnormal clinical findings, such as a breast lump or lumps that have been found by the woman or her doctor. Diagnostic mammography may also be done after an abnormal screening mammogram to determine the cause of the area of concern on the screening exam.

Talk to your doctor about your risk for breast cancer and when you should get screened. Mammograms can begin at age 40, but some women at high risk of breast cancer may need to start earlier.

Breast tomosynthesis is a breakthrough in mammography that takes multiple images of the entire breast. Our specialized breast radiologists use it to pinpoint the size, shape and location of an abnormality, allowing them to see through layers of tissue. Research on breast tomosynthesis in large populations consistently shows improved cancer detection rates and a decrease in call backs.

Breast tomosynthesis plus digital mammography is standard for all mammograms to screen for breast cancer at Mass General. They are performed together on one scanner for a complete exam that takes minutes.

3D mammography is a commonly used term for breast tomosynthesis. They both refer to the same type of mammogram. Unlike conventional digital or 2D mammography, breast tomosynthesis takes multiple images from different angles of the entire breast. Advanced imaging technology reconstructs these images to form a more detailed view compared to 2D mammography. Together, these images resemble the pages of a book. Our breast radiologists can page through the images to see through layers of breast tissue.

If our breast radiologists spot an area with the potential to be abnormal, we ask a patient to return for a diagnostic mammogram to get additional images. Many women are called back, and most receive a negative or benign result.

Breast tomosynthesis, which we use at Mass General, is associated with a decrease in call backs.

You do not need a referral from a doctor to schedule a screening mammogram, but a diagnostic mammogram typically requires one.

You can schedule a screening mammogram without a referral by contacting our locations or requesting an appointment online

Some women are concerned that dense breast tissue can obscure important information on a mammogram.

Breast tomosynthesis minimizes the effect of overlapping tissue by taking multiple images in an arc over the breast that our breast radiologists "page" though like a book to examine every area of the breast in detail. It is appropriate for breasts of various densities.

Talk to your doctor if you have any concerns about your breast health.

The small amount of radiation for the type of mammogram we perform at Mass General is below the prescribed standards set by government regulators. The benefits of mammography outweigh any possible risk associated with radiation exposure.

If our breast radiologists spot an abnormality like a lump, we ask a patient to return for a diagnostic mammogram to get additional images. In these cases, results are communicated to the patient immediately and a multidisciplinary team of breast cancer specialists at Mass General coordinates next steps if needed.