Assessing residential neighborhood exposomes and their associations with cancer incidence: rationale, study design, and methods.

Geographic and racial/ethnic disparities in cancer outcomes exist but are not fully explained. As neighborhood context significantly influences these disparities, understanding factors related to neighborhood disadvantage (ND), including historical and structural injustice, will identify key areas that could eliminate disparities. This study will address three important limitations to understanding the role of neighborhood factors on cancer outcomes, the: (1) timing of exposures during the life course, (2) identification of the most important ND variables, and (3) comprehensive assessment of several domains of neighborhood-based exposures. The neighborhood exposome comprises four domains over the life course: socioeconomic deprivation, racial segregation, environmental pollutants, and built environment. To elucidate the relationship between ND and cancer risk, we will use Virginia and Pennsylvania state cancer registry data, case and control residential histories, and data documenting multiple historical and current ND exposure indicators. The aims of this project are to determine the effects of different ND exposure domains for colorectal, lung, and female breast cancer incidence cumulatively over time using residential histories. The expected outcomes of this research will be (1) new methods for estimating ND effects over time and (2) identification of previously undetected historic ND exposures associated with significant cancer risk.