A mammogram is an X-ray examination of the breast. It is used to detect and diagnose breast disease in women who have breast problems such as a lump, pain or nipple discharge, as well as for women who have no breast complaints.
Mammography cannot prove that an abnormal area is cancer, but if it raises a significant suspicion of cancer, tissue will be removed for a biopsy. Tissue may be removed by needle or open surgical biopsy and examined under a microscope to determine if it is cancer.
Mammography has been used for about 30 years, and in the past 15 years technical advancements have greatly improved both the technique and results. Today, dedicated equipment used only for breast X-rays produce studies that are high in quality but low in radiation dose. Radiation risks are considered to be negligible.
There are two forms of mammograms, depending on the purpose:
- Screening mammogram: A screening mammogram is an X-ray of the breast used to detect breast changes in women who have no signs of breast cancer. It usually involves two X-rays of each breast. Using a mammogram, it is possible to detect a tumor that cannot be felt.
- Diagnostic mammogram: A diagnostic mammogram is an X-ray of the breast used to diagnose unusual breast changes, such as a lump, pain, nipple thickening or discharge or a change in breast size or shape. A diagnostic mammogram also is used to evaluate abnormalities detected on a screening mammogram. It is a basic medical tool and is appropriate in the workup of breast changes, regardless of a woman’s age.
The recent development of digital mammography technology shows promise for improved breast imaging. Digital mammography provides electronic images of the breasts that can be enhanced by computer technology, stored on computers and even transmitted electronically in situations where remote access to the mammogram is required.
X-rays of the breast are different than those used for other parts of the body. The breast X-ray does not penetrate tissue as easily as the X-ray used for routine X-rays of other parts of the body. The breast is compressed by the mammogram equipment to spread the tissue apart. This procedure allows for a lower dose of radiation. Compression of the breast may cause temporary discomfort, but is necessary to produce a good mammogram. The compression only lasts for a few seconds for each image of the breast. A breast health nurse or X-ray technologist usually takes the X-rays, but the resulting films are read and interpreted by a radiologist, who reports the results to your physician.
Calcifications, tiny mineral deposits within the breast tissue.
There are two categories of calcifications:
- Macrocalcifications– coarse calcium deposits that usually indicate degenerative changes in the breasts, such as:
- aging of the breast arteries
- old injuries
- Microcalcifications – tiny (less than 1/50 of an inch) specks of calcium; when many microcalcifications are seen in one area, they are referred to as a cluster
- Masses, which may occur with or without associated calcifications, and may be due to different causes, including:
- Cyst – a noncancerous collection of fluid in the breast; it cannot be diagnosed by physical exam alone nor by mammography alone. Either breast ultrasound or aspiration with a needle is required. If a mass is not a cyst, then further imaging may be obtained.
- Benign breast conditions – masses can be monitored with periodic mammography, but others may require immediate or delayed biopsy.
- Breast cancer
National Cancer Institute Guideline
American Cancer Society Guideline
Women 40 years of age
Women 40 years of age
What is the benefit?
Today’s high-quality screening mammography is the most effective tool available to physicians in detecting breast cancer before lumps can be felt or symptoms of cancer appear. Early detection of breast cancer not only helps provide a woman with more options, but also increases the possibility of a favorable prognosis.
Is there a risk of radiation exposure from having regular mammograms?
The risk of harm from radiation exposure is extremely small, and the risk decreases significantly as a woman ages. The actual exposure of radiation during a mammogram is equivalent to that of having a dental exam. The U.S. Food and Drug Administration regulates that mammograms not exceed two rads (radiation absorbed dose), the unit of measure for radiation exposure. Most mammograms actually deliver a small fraction of that amount and a woman must carefully weigh the risks of not having mammograms against that of this small radiation exposure.
What should a woman expect when having a mammogram?
A woman should avoid using deodorant and lotions and wear two-piece clothing on the day of her mammogram. A specially trained radiological technologist, who will perform the X-ray, will ask the woman to undress and stand next to the X-ray machine. Two flat surfaces, or plates, are lowered and compress each breast for a few seconds. This compression is necessary to produce the best pictures using the lowest amount of radiation possible.
Are mammograms painful?
Some women find the pressure of the plates on their breasts to be uncomfortable or even somewhat painful. Timing your mammogram when your breasts are not tender is important. In premenopausal women, this is usually one week after your menstrual period. If you do experience discomfort or pain, remember that each X-ray takes just a few moments and could save your life.
Who pays for mammography?
Medicare covers mammography screening for women 65 and older every year. Most states now require that health insurance policies offer mammography screening reimbursement. In addition, many mammography facilities also offer special programs and lower fees during National Breast Cancer Awareness Month in October.