Skip to content
My WebMD Sign In, Sign Up

Breast Cancer Health Center

Font Size
A
A
A

What Is Breast Cancer?

Each month, a woman's breasts go through temporary changes associated with menstruation and a lump may form. While the vast majority of these growths are not breast cancer, any lump should be examined immediately.

Breast lumps are most common in the lobules -- small sacs that produce milk -- or the ducts that carry milk to the nipple. But they occasionally start in other tissue. The two main categories of breast cancer are lobular and ductal carcinomas.

Recommended Related to Breast Cancer

New Mammogram Screening Guidelines FAQ

The U.S. Preventive Services Task Force (USPSTF) is recommending sweeping changes in its breast cancer screening guidelines. The USPSTF, which is a group of independent health experts convened by the Department of Health and Human Services, reviewed and commissioned research to develop computer-simulated models comparing the expected outcomes under different screening scenarios. Here are the USPSTF's recommendations, based on all that work: Routine screening of average-risk women should...

Read the New Mammogram Screening Guidelines FAQ article > >

Breast cancer usually begins with the formation of a small, confined tumor. Some tumors are benign, meaning they do not invade other tissue; others are malignant, or cancerous. Malignant tumors have the potential to metastasize, or spread. Once such a tumor grows to a certain size, it is more likely to shed cells that spread to other parts of the body through the bloodstream and lymphatic system. Different types of breast cancer grow and spread at different rates; some take years to spread beyond the breast, while others move quickly.

Men can get breast cancer, too, but they account for less than one-half of one percent of all cases. Among women, breast cancer is the most common cancer and the second leading cause of cancer deaths -- behind lung cancer.

If eight women were to live to be at least 90, one of them would be expected to develop the disease at some point during her life. Two-thirds of women with breast cancer are over 50, and most of the rest are between 39 and 49.

Fortunately, breast cancer is very treatable if detected early. Localized tumors can usually be treated successfully before the cancer spreads; and in nine in 10 cases, the woman will live at least another five years.

Once the cancer begins to spread, getting rid of it completely is more difficult, although treatment can often control the disease for years. Improved screening procedures and treatment options mean that at least seven out of 10 women with breast cancer will survive more than five years after initial diagnosis, and half will survive more than 10 years.

WebMD Medical Reference

Reviewed by Arnold Wax, MD on June 26, 2012

Today on WebMD

Breast Cancer Health Check
HEALTH CHECK
breast cancer overview slideshow
SLIDESHOW
 
cancer fighting foods
SLIDESHOW
senior woman
Article
 
Breast Cancer Treatments Improving
VIDEO
Resolved To Quit Smoking
SLIDESHOW
 
Woman getting mammogram
Article
Screening Tests for Women
SLIDESHOW
 
ovarian cancer overview slideshow
SLIDESHOW
serious woman
Article
 
what is your cancer risk
HEALTH CHECK
10 Ways to Revitalize Slideshow
SLIDESHOW