Breast cancer is the most frequently diagnosed cancer in women other than skin cancer, and is the second leading cause of cancer death in women. In 2001, breast cancer was the 6th leading overall cause of death for women in Indiana with 919 deaths, behind stroke (2,387 deaths), heart attack (2,003), lung cancer (1,633), chronic obstructive pulmonary disease (1,589), and heart failure (1,110).
In the five years from 1997 to 2001, there were 20,960 new cases of breast cancer diagnosed in Indiana, 20,806 cases (99.3%) in women and 154 cases in men. The incidence rate for invasive breast cancer in Indiana women was 130.5 and for men was 1.2. (All rates are per 100,000 persons at risk and are age-adjusted to the US 2000 standard population. See Appendix B for further information.)
While breast cancer is common in women, breast cancer in men is rare (26 cases diagnosed in 2001). Most men do not realize they have any risk of being affected. They may ignore breast lumps, attribute them to infection, or be embarrassed about finding a lump and delay seeking medical care. Breast cancer in men is frequently diagnosed at a later stage than in women. However, when the stage at diagnosis is the same, survival for men with breast cancer is similar to that for women with breast cancer.
No single cause of breast cancer has been established. Researchers generally believe that cancers are due to a series of hereditary and/or acquired genetic mutations that cause changes in cell growth and division. Approximately 5% of breast cancers are due to a known inherited mutation. The most common mutations are in the BRCA1 and BRCA2 genes. Women with these inherited mutations have a lifetime risk of breast cancer ranging from 40% to 85% and a 16% to 40% lifetime risk of ovarian cancer (though the risk of ovarian cancer may be as high as 54% for BRCA1 carriers in Ashkenazi Jewish women). Carriers of BRCA1& 2 mutations also have a higher risk of pancreatic cancer, and male carriers have an increased though still small risk of male breast cancer and an increased risk of prostate cancer.
Though, from 1997-2001, African American women had a lower incidence rate of breast cancer (117.1) than white women (130.1), they had a significantly higher mortality rate (38.9) than white females (26.9). African American women are more likely to be diagnosed at a later stage of breast cancer (34.7% regional or distant stage vs. 28.3%) than are white women. However, according to the 2002 Indiana Behavioral Risk Factor Survey, black women over age 40 are slightly more likely to have had a mammogram within the past 2 years than are similarly aged white women. In addition, age-specific incidence rates indicate that African American women are more likely to be diagnosed at a younger age than white women; that is, the age-specific breast cancer incidence rates for black women are higher for age groups under 40 and tend to be lower for age groups over 40.
