Abstract
Racial and economic segregation can create barriers to timely cancer diagnosis and adversely affect survival. This study examines the association between neighborhood-level segregation, measured by the neighborhood-Index of Concentration at Extremes (n-ICE), and stage at diagnosis (advanced [regional/distant] vs localized) for three screenable cancers in New York City.
We analyzed 98,449 incident cases (breast, 58,970; cervical, 4,790; colorectal, 34,689) using New York State Cancer Registry data (2008-2019). Census tract-level n-ICE measures of racial and/or income-based economic segregation were calculated. Age-adjusted stage-specific incidence rates and advanced-to-localized incidence rate ratios (IRRs) were measured across n-ICE quartiles.
Advanced-to-localized stage IRRs were significantly higher in the most-deprived and/or non-Hispanic Black (NHB)-concentrated areas (Q1) than the most-affluent and/or most non-Hispanic White (NHW)-concentrated areas (Q4) for breast and cervical cancer (breast: n-ICEIncome, IRRQ1=0.71 vs IRRQ4=0.48; n-ICENHB, IRRQ1=0.75 vs IRRQ4=0.53; n-ICENHB+Income, IRRQ1=0.74 vs IRRQ4=0.47; cervical: n-ICEIncome, IRRQ1=1.30 vs IRRQ4=0.97; n-ICENHB, IRRQ1=1.44 vs IRRQ4=0.99; n-ICENHB+Income, IRRQ1=1.37 vs IRRQ4=0.92) (all P-values<.01). Hispanic concentration alone (n-ICEHispanic) was not associated with disparities, but combined with economic deprivation was (breast: n-ICEHispanic+Income, IRRQ1=0.70 vs IRRQ4=0.47; cervical: n-ICEHispanic+Income, IRRQ1=1.31 vs IRRQ4=0.93) (all P-values<.01). All racialized-economic segregation measures (n-ICENHB+Income/n-ICEHispanic+Income) showed increasing IRRs with higher segregation for both cancers (all P-trend<.04). No disparities were observed for colorectal cancer.
Racialized-economic segregation in New York City was associated with higher advanced-stage diagnoses of breast and cervical cancer but not colorectal cancer. These findings may partially reflect both structural barriers that delay timely diagnosis and the impact of local equity-driven initiatives that broaden colorectal cancer screening access.