Race-specific geography of prostate cancer incidence

Abstract

Background: This study evaluated geographic distribution of race-specific prostate cancer incidence in Connecticut and Massachusetts. This cross-sectional analysis of census and cancer registry data included records of 29,040 Whites and 1,647 African Americans diagnosed with incident prostate cancer between 1994 and 1998. A spatial scan statistic was used to detect and test significance of the geographic variation in race-specific incidence rates within the two-state area.

Results: Significant geographic variation in age-adjusted incidence rates among both White and African American men was observed, with little overlap noted between distributions. Identified locations reflected patterns of residential segregation and socio-economic conditions. Among Whites, places with higher than expected incidence had higher socioeconomic status than places with lower than expected incidence. No discernable relationship between social indicators and rate variation among African Americans was evident.

Conclusion: Differences in race-specific geographic distribution of prostate cancer incidence do not suggest a shared environmental etiology. Further study of genetic, behavioral and health care factors affecting the occurrence and/or reporting of the disease is warranted. This study highlights the need for race- and geographic-specific interventions to better control disease within at-risk communities and for on-going analysis into social and contextual factors that contribute to observed disparities between African Americans and Whites in the occurrence of cancer.

Figure 1

Spatial analysis of White residents of Connecticut (CT) and Massachusetts (MA). Population density† (1990) and geographic variation of age-adjusted invasive prostate cancer incidence rates (1994–98) among Whites residents of CT and MA. †Men 20+ years old per square mile.

Figure 2

Spatial analysis of Black residents of Connecticut (CT) and Massachusetts (MA). Population density† (1990) and geographic variation of age-adjusted invasive prostate cancer incidence rates (1994–98) among Black residents of CT and MA. †Men 20+ years old per square mile.

Figure 3

Spatial analysis of Black residents of Connecticut and Massachusetts adjusted for White resident analysis. Population density† (1990) and geographic variation of age-adjusted invasive prostate cancer incidence rates (1994–98) among Black residents of CT and MA, adjustment for spatial distribution of incidence rates specific to Whites. †Men 20+ years old per square mile.