What Is Breast Cancer?

There are many kinds of cancer. Cancer means the growth and spread of cells that are not normal. Each of us has trillions of cells that allow our body to perform normal functions like breathing, walking, and thinking. When cells stop behaving normally, they can become cancer cells.

Your breasts, like all parts of your body, are made up of cells that are too small to see. These cells can form a mass called a “growth” or a “tumor” (TOO-mer). Most tumors do not contain cancer, but sometimes they do. When this happens in your breast, it is called breast cancer.

Early breast cancer may have no symptoms at all— there will be no pain and nothing will look or feel wrong. That is why it is so important to be screened (screening is when you or your doctor look for cancer even if you don’t have any symptoms).

Breast cancer is one of the most common cancers in women. Most doctors feel that finding breast cancer early through screening saves thousands of lives.

These are changes in the breasts that may be warning signs of cancer:
• A lump in or near your breasts or under your arms
• A change in size or shape of one of your breasts
• A discharge from nipples or nipple pain
• One of your nipples turns inward
• The skin in your breast area has ridges or pitting, like the skin of an orange
• Changes in the skin of your breast, your nipples, or the area around your nipples—for example, if an area is red or the skin is scaly

These symptoms most often are not a sign of cancer. They are usually a sign of another less serious health problem. But it is important to get them checked by a doctor as soon as you can.

The earlier breast cancer can be found, the more likely treatment will work. If cancer is found in your breasts, your doctor will talk to you about what type of treatment is right for you.

Who Gets Breast Cancer?
As you get older, your chances of getting breast cancer increase—about 80% of breast cancer is in women who are 50 or older. You also have more chance of getting breast cancer (you are at higher risk) if:
• Your sister, mother, or daughter has had breast cancer. A family history nearly doubles your risk.
• You have had breast cancer before.
• You have gained weight after the change of life (menopause) or after turning 60.
• You have been on combined hormone replacement therapy (estrogen and progesterone) for several years. Talk to your doctor about the risks and benefits of your current hormone replacement therapy.
• You have had radiation treatment to your chest area in the past.

There are some things you can do to lower your risk:
• Get a mammogram every year if you are 40 or older (the American Cancer Society recommends this). Speak to your doctor if you have had a family history of breast cancer to see if you should have a mammogram done at a younger age.
• Have a breast exam done by your doctor every year.
• Learn how to do a breast self-exam and do it monthly. Have your doctor or nurse show you how to do this.
• Add healthy habits to your routine: Cut down on the red meat you eat and eat more fruits and vegetables. Cut down on how much alcohol you drink. Be more active—do more walking and try to exercise more. Lose extra weight.
• See your doctor regularly.

Provided as an educational resource by Merck