Spatial Distribution and Determinants of Thyroid Cancer Incidence from 1999 to 2013 in Korea

We evaluated the spatial variation in thyroid cancer incidence and its determinants in Korea considering its importance in cancer prevention and control. This study was based on the ecological design with cancer incidence data by administrative district from the National Cancer Center and regional characteristics generated from the Korea Community Health Survey Data. We identified spatial clusters of thyroid cancer incidences based on spatial scan statistics. Determinants of regional variation in thyroid cancer incidence were assessed using the Besag-York-Mollie model with integrated nested Laplace approximations. Spatial clusters for low and high thyroid cancer incidences were detected in the northeastern and southwestern regions, respectively. Regional variations in thyroid cancer incidence can be attributed to the prevalence of recipients of basic livelihood security (coefficient, - 1.59; 95% credible interval [CI], - 2.51 to - 0.67), high household income (coefficient, 0.53; 95% CI, 0.31 to 0.76), heavy smoking (coefficient, - 0.91; 95% CI, - 1.59 to - 0.23), thyroid dysfunction (coefficient, 3.24; 95% CI, 1.47 to 5.00), and thyroid cancer screening (coefficient, 0.38; 95% CI, 0.09 to 0.67). This study presented the spatial variations in thyroid cancer incidence, which can be explained by the prevalence of socioeconomic factors, thyroid cancer screening, thyroid dysfunction, and smoking.