A mammogram is an x-ray picture of the breast.
Mammograms can be used to check for breast cancer in women who have no signs or symptoms of the disease. This type of mammogram is called a screening mammogram. The x-ray images make it possible to detect tumors that cannot be felt. Screening mammograms can also find microcalcifications (tiny deposits of calcium) that sometimes indicate the presence of breast cancer.
Mammograms can also be used to check for breast cancer after a lump or other sign or symptom of the disease has been found. This type of mammogram is called a diagnostic mammogram. Besides a lump, signs of breast cancer can include breast pain, thickening of the skin of the breast, nipple discharge, or a change in breast size or shape; however, these signs may also be signs of benign conditions. A diagnostic mammogram can also be used to evaluate changes found during a screening mammogram or to view breast tissue when it is difficult to obtain a screening mammogram because of special circumstances, such as the presence of breast implants.
How are screening and diagnostic mammograms different?
Diagnostic mammography takes longer than screening mammography because more x-rays are needed to obtain views of the breast from several angles. The technician may magnify a suspicious area to produce a detailed picture that can help the doctor make an accurate diagnosis.
What are the benefits of screening mammograms?
Early detection of breast cancer with screening mammography means that treatment can be started earlier in the course of the disease, possibly before it has spread. Results from randomized clinical trials and other studies show that screening mammography can help reduce the number of deaths from breast cancer among women ages 40 to 74, especially for those over age 50.
What are some of the potential limitations of screening mammograms?
False-positive results. False-positive results occur when radiologists decide mammograms are abnormal but no cancer is actually present. All abnormal mammograms should be followed up with additional testing (diagnostic mammograms, ultrasound, and/or biopsy) to determine whether cancer is present.
False-positive results are more common for younger women, women who have had previous breast biopsies, women with a family history of breast cancer, and women who are taking estrogen (for example, menopausal hormone therapy).
What is the best method of detecting breast cancer as early as possible?
Getting a high-quality screening mammogram and having a clinical breast exam on a regular basis are the most effective ways to detect breast cancer early.
Checking one’s own breasts for lumps or other unusual changes is called a breast self-exam, or BSE. This type of exam cannot replace regular screening mammograms or clinical breast exams. In clinical trials, BSE alone was not found to help reduce the number of deaths from breast cancer.
Although regular BSE is not specifically recommended for breast cancer screening, many women choose to examine their own breasts. Women who do so should remember that breast changes can occur because of pregnancy, aging, or menopause; during menstrual cycles; or when taking birth control pills or other hormones. It is normal for breasts to feel a little lumpy and uneven. Also, it is common for breasts to be swollen and tender right before or during a menstrual period. If a woman notices any unusual changes in her breasts, she should contact her health care provider.
How much does a mammogram cost?
For most women with private insurance, the cost of screening mammograms is covered without copayments or deductibles, but women should contact their mammography facility or health insurance company for confirmation of the cost and coverage.
Medicare pays for annual screening mammograms for all female Medicare beneficiaries who are age 40 or older. Medicare will also pay for one baseline mammogram for female beneficiaries between the ages of 35 and 39. There is no deductible requirement for this benefit. Information about coverage is available on the Medicare website or through the Medicare Hotline at 1–800–MEDICARE (1–800–633–4227). For the hearing impaired, the telephone number is 1–877–486–2048.
How can uninsured or low-income women obtain a free or low-cost screening mammogram?
Some state and local health programs and employers provide mammograms free or at low cost. For example, the Centers for Disease Control and Prevention (CDC) coordinates the National Breast and Cervical Cancer Early Detection Program. This program provides screening services, including clinical breast exams and mammograms, to low-income, uninsured women throughout the United States and in several U.S. territories. Contact information for local programs is available on the CDC website or by calling 1–800–CDC–INFO (1–800–232–4636).
Information about free or low-cost mammography screening programs is also available from NCI’s Cancer Information Service at 1–800–4–CANCER (1–800–422–6237) and from local hospitals, health departments, women’s centers, or other community groups.
What should women with breast implants do about screening mammograms?
Women with breast implants should continue to have mammograms. (A woman who had an implant following a mastectomy should ask her doctor whether a mammogram of the reconstructed breast is necessary.) It is important to let the mammography facility know about breast implants when scheduling a mammogram. The technician and radiologist must be experienced in performing mammography on women who have breast implants. Implants can hide some breast tissue, making it more difficult for the radiologist to detect an abnormality on the mammogram. If the technician performing the procedure is aware that a woman has breast implants, steps can be taken to make sure that as much breast tissue as possible can be seen on the mammogram. A special technique called implant displacement views may be used.