BREAST CANCER

Breast Cancer

Breast Cancer

We assessed whether population rates of mammography screening, and their changes over time, were associated with improvements in breast cancer stage at diagnosis and whether the strength of this association varied by race/ethnicity.

We analyzed state cancer registry data linked to socioeconomic characteristics of patients' areas of residence for 1990-1998 time trends in the likelihood of early stage diagnosis. We appended each cancer registry record with matching subgroup estimates of self-reported mammography screening.

Trends in screening and stage at diagnosis were consistent within groups, but African American women had a significantly lower proportion of early stage cancers despite an advantage in screening. Population screening rates were significantly associated with early diagnosis, with a weaker association in African American women than White women (odds ratio [OR] = 1.70; P<.0001 vs OR=2.02; P<.0001, respectively).

Improvements in screening rates during the 1990s across racial/ethnic groups appear to have contributed significantly to earlier diagnosis within each group, but a smaller effect in African American women should raise concerns. A key health policy challenge is to ensure that screening effectively translates into earlier diagnosis.

Breast cancer is the second leading cause of cancer deaths in women today (after lung cancer) and is the most common cancer among women, excluding nonmelanoma skin cancers. According to the American Cancer Society, about 1.3 million women will be diagnosed with breast cancer annualluy worldwide about 465,000 will die from the disease. Breast cancer death rates have been dropping steadily since 1990, according to the Society, because of earlier detection and better treatments. About 40,910 breast cancer deaths are expected in 2007.

According to the American Cancer Society, in general, breast cancer rates have risen about 30% in the past 25 years in western countries, due in part to increased screening which detects the cancer in earlier stages. In the ...