Geographic variations in breast cancer mortality: do higher rates imply elevated incidence or poorer survival?

OBJECTIVES: Mortality rates from breast cancer are approximately 25% higher for women in the northeastern United States than for women in the South or West. This study examined the hypothesis that the elevation is due to decreased survival rather than increased incidence. METHODS: Data on breast cancer incidence, treatment, and mortality were reviewed. RESULTS: The elevated mortality in the Northeast is apparent only in older women. For women aged 65 years and older, breast cancer mortality is 26% higher in New England than in the South, while incidence is only 3% higher. Breast cancer mortality for older women by state correlates poorly with incidence (r = 0.28). CONCLUSIONS: Those seeking to explain the excess breast cancer mortality in the Northeast should assess survival and should examine differences in cancer control practices that affect survival.