What is a mammogram?

A mammogram is an X-ray of the breasts. A mammogram is an important screening test for breast cancer. Used along with other tests, a mammogram can help detect breast cancer at an early stage when it is most curable. A mammogram can find some lumps or abnormalities that you or your doctor may not feel with a manual breast exam. A mammogram will create a detailed image of the breast to show the size and shape of a lump or change in the breast. 

A normal mammogram shows no breast lumps or other irregularities in the images. An abnormal result might indicate benign (noncancerous) tumors, cysts, breast cancer (cancerous tumors), calcium deposits, or dense areas of breast tissue. A radiologist will review your mammogram images and discuss them with your doctor. Your doctor will then discuss the results with you. Together, you will decide what next steps (if any) you need to take based on the mammogram results.

A mammogram is only one method used to screen for breast cancer and other breast abnormalities. Discuss all of your screening options with your doctor to understand which methods should be used and when.

Other procedures that may be performed 

A mammogram alone cannot diagnose cancer. Your doctor will probably recommend further testing if a mammogram finds an abnormality. Other tests include:

  • Magnetic resonance imaging (MRI) makes a detailed, high-resolution picture of your breast. An MRI provides much more detail than an X-ray.
  • Tissue biopsy of the lump or abnormal area. A tissue biopsy involves removing a sample of breast cells or tissues and testing it for cancer in the laboratory.
  • Ultrasound uses sound waves to make a picture of your breast. Ultrasound may be used to tell whether a lump is solid or filled with fluid or to guide a breast biopsy of a mass.

Why is a mammogram performed?

Your doctor may recommend a mammogram to diagnose or screen for diseases and conditions of the breast. A mammogram is used for:

  • Diagnosis of breast irregularities that you or your doctor sees or finds during a breast exam. These include lumps, pain, nipple discharge, or changes in breast shape or texture. 
  • Follow-up on previous abnormal mammograms to track the progress of any lumps or irregularities
  • Screening for breast cancer in otherwise healthy women with no symptoms

Who performs a mammogram?

A radiologic technologist, supervised by a radiologist, usually performs a mammogram. A radiologic technologist is a medical professional who performs imaging procedures and takes care of patients during the procedures. 

A radiologist or diagnostic radiologist evaluates a mammogram. Radiologists specialize in using radiation and other imaging techniques to diagnose and treat a wide variety of conditions from broken bones and birth defects to cancer. Diagnostic radiologists focus on performing and interpreting imaging tests, such as ultrasounds, X-rays, angiograms, CTs, and MRIs. 

How is a mammogram performed?

Your mammogram will be  performed in a hospital or outpatient setting. Mammograms take less than an hour and generally include these steps:

  1. You will undress and remove all jewelry from the waist up and wear your own clothing from the waist down. 
  2. You will stand or sit in front of the mammography machine, depending on which type of machine it is. 
  3. The radiologic technologist will place one of your breasts at a time on an X-ray plate. A compressor will compress and flatten your breasts between two plates to spread out the tissue. This helps the machine to get the clearest possible images. 
  4. The radiologic technologist will leave the room and take a few pictures of your breast from different angles with the X-ray machine. He or she may ask you to hold your breath during each picture. 
  5. When the pictures are complete, the machine will release your breast from compression.
  6. The radiologic technologist repeats this process with your other breast.
  7. Once the exam is complete, you may get dressed and relax.
  8. You may wait a short period of time while the radiologic technologist or radiologist verifies that the imaging is complete. You will probably go home right after the exam.