Exploring ethnic diversity and clinical outcome variabilities in well-differentiated thyroid cancer among the Asian population.

Background: Well-differentiated thyroid cancer includes papillary thyroid, follicular thyroid, and Hurthle cell cancers, comprising approximately 95% of all thyroid cancers in the United States. This study aims to understand well-differentiated thyroid cancer in the Asian population.

Methods: We analyzed the National Cancer Database from 2004 to 2019, categorizing the Asian population based on the available ethnicities. Multivariable logistic regression assessed the associations between ethnic groups and disease stage/nodal positivity. Survival outcomes were evaluated using the Kaplan-Meier and Cox regression analyses.

Results: A total of 364,604 adult patients were analyzed. The Asian ethnic groups included were Chinese (n = 3,851), Japanese (n = 740), Filipino (n = 3,466), Korean (n = 1,567), Vietnamese (n = 1,517), Laotian (n = 101), Hmong (n = 50), Kampuchean (n = 166), Thai (n = 160), Asian Indian (n = 1,526), Pakistani (n = 167), and Pacific Islander (n = 446). Japanese, Korean, and Laotian had higher percentages of stage III disease, whereas Japanese, Filipino, and Laotian had higher proportions of stage IV disease than the White population. Most Asian ethnicities had more patients with metastasis than the White population. Korean patients exhibited a 15% increased likelihood of metastasis (odds ratio: 1.15, confidence interval: 1.03-1.28, P < .05), whereas Pakistani patients were at 40% higher odds (odds ratio: 1.40, confidence interval: 1.03-1.91, P < .05), compared with White patients. Japanese, Laotian, and Kampuchean patients experienced worse 5- and 10-year overall survival than the White population.

Conclusion: Our study revealed substantial variation in well-differentiated thyroid cancer characteristics and outcomes among diverse Asian ethnicities. This challenges the notion of Asians as a homogeneous population, emphasizing tailored disease management for this heterogeneous group of patients.