Characterizing gastric cancer and time-to-first treatment among non-Hispanic American Indian Alaska Native and white patients in North Carolina.

PURPOSE: This study aimed to characterize the gastric cancer burden among non-Hispanic American Indian Alaska Native (NHAIAN) and White (NHW) individuals in North Carolina to provide a baseline assessment of the gastric cancer burden in North Carolina.

METHODS

Data from the North Carolina Central Cancer Registry (2003-2021) were used to construct gastric cancer diagnosis (NHAIAN n = 111; NHW n = 7,685) and treatment (NHAIAN n = 97; NHW n = 6,040) cohorts. Race-stratified patient characteristics were summarized. We evaluated unadjusted associations between patient characteristics and receipt of no treatment and the multivariable-adjusted association risk ratio (RR) between race and no treatment using modified Poisson regression. Race-specific cumulative incidence functions (CIFs) for treatment initiation were estimated with bootstrapped 95% confidence intervals (CI) and adjusted for key covariates using inverse probability weighting.

RESULTS

NHAIANs were diagnosed at a younger age (65 vs 68 years; p = 0.006), with non-cardia cancer (80 vs 62%; p < 0.001), at a later stage (36 vs 32%; p = 0.021), and lived in an area with a lower residential population density than NHW gastric cancer patients (76 vs 26%; p < 0.001). The risk of not initiating treatment was higher among NHAIANs compared to NHWs (RR = 1.13 (95% CI = [0.87, 1.47]; p= 0.34). The CIF for treatment initiation was consistently lower for NHAIANs with a significant difference at 30 days (CIF difference = -0.09; 95% CI = [-0.17, -0.01]).

CONCLUSION

NHAIAN gastric cancer patients in North Carolina were diagnosed younger, at more advanced stages, and had a lower cumulative probability of initiating treatment within the first year after diagnosis compared to NHWs.