Early detection of breast cancer: What you need to know

During the screening, each breast is compressed between two plates of a mammography machine.

Breast cancer is the most common cancer among women globally and the second most common in the United States. In the U.S., the average risk of a woman developing breast cancer sometime in her life is roughly 13%, or a one in eight chance. However, the five-year survival rate for localized breast cancer — cancer that is contained to the breast — is more than 99%.

Early detection of breast cancer, through regular mammograms or other screening methods, can give people the best chance at effective treatment and can be lifesaving. Knowing what to look for and when to get screened can help catch breast cancer early, when it's most treatable.

Breast cancer screening guidelines

For women who are at average risk, the American Cancer Society recommends annual mammograms between the ages of 45 and 54. Depending on your history and risk factors, your doctor may suggest starting annual screenings as early as 40. For women 55 and older, the American Cancer Society recommends screenings every other year, but consult your doctor before making the decision to stop screening. A general guideline is to keep up with screenings regularly as long as you're in good health and expect to live at least 10 more years.

If you're considered high risk for breast cancer, you should begin annual screenings with both breast MRIs and mammograms around age 30. If you're unsure about your risk level, talk to your doctor. They can help you complete a risk assessment and decide whether earlier or more intensive screening is right for you.

Personal risk factors for breast cancer

The main risk factors for breast cancer are being a woman and getting older. Most breast cancers are found in women age 50 and older. Other risk factors include:

• Genetic mutations (such as BRCA1 or BRCA2)
• Early menstruation or late menopause
• Dense breast tissue
• Prior breast cancer or certain benign breast diseases
• Physical inactivity
• Long-term hormone therapy
• Heavy alcohol use
• Strong family history of breast cancer
• Chest radiation before age 30

Having a risk factor does not mean you will get breast cancer. But knowing you have a risk factor can help you be prepared and know what to look for. If you are concerned, talk to your doctor about ways to lower your risk.

What to expect during a mammogram

There are two types of mammograms:

• A screening mammogram is an X-ray that looks for unsuspected breast cancer in women who do not have symptoms.
• A diagnostic mammogram examines abnormalities, usually after they are spotted on a screening mammogram.

When you show up for your mammogram, you will need to undress just to your waist for your exam, so consider wearing a two-piece outfit. During the screening, each breast is compressed between two plates of a mammography machine. X-rays are taken of each breast from the front and the side.

The pressure and positioning required with mammograms can be uncomfortable. It may help to know that the screening portion of the appointment only takes about 10 to 15 minutes. Diagnostic mammograms can take longer than screening mammograms because more images are needed.

What to check between mammograms

Medical organizations have shifted from formal monthly breast self-exams to encouraging women to simply become familiar with their breasts and how they normally look and feel. This can make it easier to recognize any changes.

To familiarize yourself with your breasts:

• Do a visual inspection in front of a mirror with your hands on your hips and a second with your arms raised above your head. Look for visual changes such as redness, swelling or puckering. Also look for nipple inversion (a nipple that is pushed inward rather than sticking out) or dimpling.
• Manually inspect your breasts for lumps, knots or thickened areas. Gradually increase pressure as you go around the breast and squeeze the nipple to check for discharge. You'll want to do this twice — while standing up and while lying down. Be sure to cover the entire breast and armpit area.

It can help to explore what your breasts normally feel and look like a few days after your period ends. Hormone levels fluctuate throughout the month, causing changes in breast tissue such as swelling and tenderness.

Know your risk

Talking with your doctor about your personal risk factors, keeping up with recommended screenings and paying attention to changes in your body can lead to early detection of breast cancer and better outcomes.