Disparities in Thyroid Cancer Diagnosis Based on Residence and Distance From Medical Facility

Abstract

Abstract Context Rural-urban disparities have been reported in cancer care, but data are sparse on the effect of geography and location of residence on access to care in thyroid cancer. Objective To identify impact of rural or urban residence and distance from treatment center on thyroid cancer stage at diagnosis. Methods We evaluated 800 adults with differentiated thyroid cancer in the iCaRe2 bioinformatics/biospecimen registry at the Fred and Pamela Buffett Cancer Center. Participants were categorized into early and late stage using AJCC staging, and residence/distance from treating facility was categorized as short (≤ 12.5 miles), intermediate (> 12.5 to < 50 miles) or long (≥ 50 miles). Multivariable logistic regression was used to identify factors associated with late-stage diagnosis. Results Overall, 71% lived in an urban area and 29% lived in a rural area. Distance from home to the treating facility was short for 224 (28%), intermediate for 231 (28.8%), and long for 345 (43.1%). All 224 (100%) short, 226 (97.8%) intermediate, and 120 (34.7%) long distances were for urban patients; in contrast, among rural patients, 5 (2.16%) lived intermediate and 225 (65.2%) lived long distances from treatment (P < .0001). Using eighth edition AJCC staging, the odds ratio of late stage at diagnosis for rural participants ≥ 55 years was 2.56 (95% CI, 1.08-6.14) (P = .03), and for those living ≥ 50 miles was 4.65 (95% CI, 1.28-16.93) (P = .0075). Results were similar using seventh edition AJCC staging. Conclusion Older age at diagnosis, living in rural areas, and residing farther from the treatment center are all independently associated with late stage at diagnosis of thyroid cancer.