Unexpected high-risk pathologic features following thyroidectomy in the chinese immigrant population.

Objective: To compare rates of unexpected high-risk pathologic features between Chinese and non-Asian patients who underwent thyroidectomy for papillary thyroid cancer.

Methods: This was a retrospective cohort study at a tertiary academic urban medical center. Patients who underwent thyroidectomy for papillary carcinoma from 2015 to 2017 were included. Patient demographics, tumor characteristics, and tumor histopathology were analyzed. Primary outcome was the presence of adverse histopathologic features such as lymphovascular invasion (LVI) or microscopic/minimal extrathyroidal extension (mETE). Differences between the groups were analyzed using multivariate logistical regression analysis and propensity score-weighted analysis.

Results: One hundred seventy-nine patients were included: 58 Chinese-born and 121 non-Asian. The median age of the cohort was 47 years old (36-58). Twenty-nine percent of patients were male, and 71% were female. There was no statistically significant difference between the two cohorts in rates of LVI, multifocality, extent of surgery, or presence of thyroiditis. Patients with mETE were more likely to have larger tumors (P = 0.00247). Both the multivariate and propensity-weighted models demonstrated that Chinese ancestry was independently associated with an increased rate of unexpected mETE (adjusted prevalence ratio, 2.52; 95% confidence interval, 1.82-3.48).

Conclusion: mETE is significantly higher in the immigrant Chinese compared to the non-Asian population. Given the high prevalence of unexpected mETE in the Chinese population, the added risk of this finding should be brought into the discussion during initial surgical planning.

Level Of Evidence: 3 Laryngoscope, 130:1844-1849, 2020.