INCIDENCE
Breast cancer is the most common form of cancer among women in industrialized countries. The incidence of breast cancer increases with age, beginning slowly between the ages of 45 and 50 years and then rising steadily each year thereafter. More than 70% of breast cancers occur in women 50 years of age and older. In 2007, 178,480 new cases of breast cancer are expected to be diagnosed in women living in the United States. Breast cancer is the leading cause of cancer deaths for women between 20 and 59 years of age with a projected death rate of 40,910 in 2007. Male breast cancer accounts for less than 1% of all breast cancers, with an estimated 2,030 new cancers diagnosed and 450 breast cancer deaths in 2007.