A recent report using the North Carolina State Registry has highlighted that North Carolina’s urban counties may have higher overall incidences of breast cancer than its rural counties, especially at early stages at diagnosis. In this study, the investigators used North Carolina Central Cancer Registry data to analyze the breast cancer incidence rates in individuals residing in various geographic areas of North Carolina. The investigators further evaluated the different breast cancer stages stratified by rural or urban status.

Because North Carolina has a diverse population of 10 million individuals spread over 100 rural and urban counties, with varying environmental conditions, the investigators noted the state served as an effective model.

Compared with the counties that had a good environmental quality, the investigators found the counties with a poor overall environmental quality had a total breast cancer incidence that was higher by 10.82 cases per 100,000 individuals. This association was most pronounced for localized breast cancer.

Additionally, the investigators discovered the community-level effects of environmental exposures - notably in counties with poor land quality caused by pesticides and toxic releases from industrial, agricultural, and animal facilities - were correlated with higher rates of total breast cancer incidence, especially in urban settings. The investigators revealed the breast cancer incidence rates were also higher for later-stage disease and total breast cancer among counties with higher populations of Black individuals. They suggested these findings may be relevant, since the global incidence of aggressive breast cancer is higher in Black women.

This study is another example of the importance of state cancer registries.