The role of rurality and race/ethnicity in thyroid cancer stage at diagnosis and survival among adolescents and young adults in the United States: an analysis of 2000-2021 SEER data.

PURPOSE: Relatively few studies have focused on thyroid cancer in the adolescent and young adult (AYA) population. The objective of this study was to examine racial/ethnic and geographic predictors of thyroid cancer stage at diagnosis and survival in the AYA population.

METHODS

This population-based longitudinal study uses data from the Surveillance, Epidemiology, and End Results (SEER)-22 registries database. Primary cases of malignant thyroid cancer from 2000 to 2021 diagnosed among individuals aged 15-39 were included. Multinomial logistic regression models were used to examine the association between race/ethnicity and rurality (measured using Rural Urban Continuum codes) with stage at diagnosis (measured using SEER summary stages). Cox proportional hazards regression models were used to examine the association between race/ethnicity and rurality and both cancer-specific and all-cause mortality.

RESULTS

Our study included 74,215 AYAs with thyroid cancer. Approximately, 8% of the cases resided in rural counties. The association between race/ethnicity and stage at diagnosis differed by rurality (p = 0.010). Among AYAs with thyroid cancer, living in a rural county at diagnosis was associated with an increased hazard of all-cause mortality (aHR = 1.41, 95% CI 1.13-1.76). Additionally, compared to non-Hispanic White AYAs, the hazard of thyroid cancer-specific mortality was highest among non-Hispanic Black (aHR = 3.66, 95% CI 2.37-5.65) and Hispanic (aHR = 1.85, 95% CI 1.32-2.60) AYAs.

CONCLUSION

We observed racial and geographic differences in thyroid cancer stage at diagnosis and survival among AYAs in the USA. Future research should explore the underlying causes of these disparities and identify potential opportunities for intervention.