Who should have mammograms and how often?

Women age 40 and older should have a screening mammogram every one to two years, according to the National Cancer Institute. Women who are at increased risk of breast cancer should talk with their doctor about when to begin having screening mammograms and how often to have them.

A screening mammogram is an x-ray that is used to find breast changes in women who have no signs or symptoms of breast cancer. Several large studies have found that screening mammograms reduce breast cancer deaths among women ages 40 to 69.

Mammograms have limitations as well. Finding a small tumor does not always mean that a women's life will be saved. A fast-growing or aggressive cancer may have already spread to other parts of the body before being found.

Also, mammograms aren't always accurate. They miss up to 20 percent of breast cancers that are present at the time of screening. This happens mostly with younger women because their breast tissue is often dense, making it more difficult to see tumors on the x-ray. Mammograms also may show an abnormality when no cancer is present. This is most common in younger women, women who have had previous breast biopsies, women with a family history of breast cancer, and women who are taking estrogen.

Still, a mammogram, along with a breast exam by a health professional, is currently the best way to find breast cancer early.

For more information on mammograms, including where to get a high-quality mammogram, talk with your doctor or call the Cancer Information Service at 1-800-4-CANCER.

Source:  "Ask the CIS" by the Cancer Information Service.  "Ask the CIS" is distributed by the Cancer Information Service (CIS) of the Heartland, which serves Kansas, Nebraska, Missouri & Illinois. The CIS is a program of the National Cancer Institute. Call the CIS toll-free at 1-800-4-CANCER (1-800-422-6237) between 9 a.m. and 4:30 p.m. local time.