About Breast Cancer
Breast cancer is a malignant (cancerous) tumor that starts from cells of the breast. The disease occurs mostly in women, but men can get breast cancer too. The information here refers only to breast cancer in women.
Breast cancer is the most common cancer among American women, except for skin cancers. The chance of developing invasive breast cancer at some time in a woman's life is about 1 in 8 (12%). It is estimated that in 2007 about 178,480 new cases of invasive breast cancer will be diagnosed among women in the United States. Women living in North America have the highest rate of breast cancer in the world. At this time there are about 2.5 million breast cancer survivors in the United States.
In addition to invasive breast cancer, carcinoma in situ (CIS) will account for about 62,030 new cases in 2007. CIS is non-invasive and is the earliest form of breast cancer.
Breast cancer incidence rates showed a rapid increase in the 1980s, although the rate of increase slowed in the 1990s compared to the 1980s. In the years from 2000 to 2004, incidence rates decreased slightly.
Breast cancer is the second leading cause of cancer death in women, exceeded only by lung cancer. The chance that breast cancer will be responsible for a woman's death is about 1 in 35 (about 3%). In 2007, about 40,460 women will die from breast cancer in the United States. Death rates from breast cancer have been declining since about 1990, with larger decreases in women younger than 50. These decreases are believed to be the result of earlier detection through screening and increased awareness, as well as improved treatment.