BREAST cancer screening includes tests to detect breast cancer at an early stage, before a woman discovers a lump. The chance of dying from breast cancer has declined by about a third over the past few decades. This is due, in part, to the use of breast cancer screening to find cancer at an earlier stage. Breast cancer is more likely to be cured when it is caught earlier.

There are three main ways to screen for breast cancer: mammogram, breast exam with your doctor or nurse, and breast self-exam.

A mammogram is a breast X-ray. It is the best screening test for reducing the risk of dying from breast cancer. Before the mammogram, you will be asked to undress from the waist up and wear a hospital gown. Each breast is X-rayed individually. The breast is flattened between two panels. This can be uncomfortable, but it only takes a few seconds. If possible, try to avoid scheduling your mammogram just before or during your menstrual period, when the breasts are more sensitive. Also, do not use underarm deodorant on the day of your appointment.

A radiologist will review and interpret the mammogram. Sometimes the radiologist reviews the mammogram images while you wait. Some women will need to have more images taken. Needing more images is common and does not usually mean that you have cancer. These extra images help the radiologist to have the most accurate and clear view of your breast tissue.

If the radiologist does not review your mammogram immediately, you should get a phone call or letter with your results within 30 days. If you do not hear back, call your doctor or nurse's office. You should not assume that your mammogram was normal.

If your mammogram is abnormal, you will need further testing. In most cases, a woman with an abnormal mammogram does not have breast cancer. In 90 percent of women with an abnormal mammogram, breast cancer is not found.

Breast MRI

Magnetic resonance imaging (MRI) uses a strong magnet rather than X-rays to create a detailed image. Compared to mammograms, breast MRI has more "false positive" findings (changes that are not breast cancer), and may lead to more unnecessary biopsies in women who are not at high risk for breast cancer. Breast MRI may be recommended, in addition to mammography, to help find breast cancer in young women with a high risk for developing breast cancer (such as those with a very strong family history or a breast cancer gene). However, breast MRI is not recommended to screen for breast cancer in women who do not have a high risk of breast cancer.

All expert groups agree that women age 50 and older should have screening for breast cancer (including a mammogram and a breast exam). There is controversy about use of mammograms among women in their 40s because on average, breast cancer is less common in the 40s while the chances of having an abnormal mammogram that must be worked up are higher.

Some expert groups recommend starting mammograms at age 40. Other groups recommend that women between ages 40 to 49 talk to their doctor or nurse about the risks and benefits of mammograms. Your decision to have or delay mammograms between ages 40 to 49 should be based on your individual preferences and risk of breast cancer.

Women who choose to have breast cancer screening beginning at age 40 are usually screened once per year until age 50. After age 50, most expert groups recommend breast cancer screening every one to two years, depending on the woman's individual risk.

Most expert groups recommend that women continue to get routine mammograms and clinical breast exams as long as the woman is expected to live at least 10 years. This is because the risk of developing breast cancer increases as women age.