(1067) Trends and Predictors of Positive Surgical Margins in Pediatric Thyroid Cancer

Introduction: Positive margin status (PM) has been significantly associated with an increased risk of death for multiple forms of cancer. Given the significant increase in pediatric thyroid cancer incidence over the past two decades, understanding trends and predictors of positive surgical margins is important.

Methods: A retrospective analysis of the National Cancer Database (NCDB) was conducted to identify pediatric patients diagnosed with thyroid cancer between 2004-2020. The PM rate by year of diagnosis was calculated. Linear regression analysis between PM rates and year was conducted. Kaplan-Meier analysis was used to analyze the impact of margin status on overall survival. Multivariable logistic regression was used to investigate predictors of PM.

Results: For analysis, 6625 patients met inclusion criteria between 2004 and 2020. Of all included patients, 15.6% (N=1032) of patients experienced a positive margin. Between 2004 and 2020, the PM rate did not significantly change (beta=0.88, 95% CI -2.5 – 0.71, p=0.257). Ten-year overall survival (OS) was 98.8% for those without and 97.6% for those with PM (Log-rank p=0.100). On multivariable logistic regression, stage 4 (OR 6.81, 3.88-12.1, p< 0.001), female sex (OR 0.74, 0.62-0.89, p=0.001), age (OR 0.92, 0.89-0.94, p< 0.001), and private (ref = Medicaid; OR 0.54, 0.31-0.98, p=0.034) and government (ref = Medicaid; OR 0.43, 0.19-0.98, p=0.046) insurance were associated with PM.

Conclusions: PM in pediatric thyroid cancer is common and has not significantly changed over the past 20 years. PM do not impact overall survival in this patient population. Further studies are required to investigate the impact on disease-free survival. Patient-specific factors, notably insurance status, decrease PM suggesting sociodemographic disparities exist.