Delay in Surgery and Papillary Thyroid Cancer Survival in the United States: A SEER-Medicare Analysis

Introduction Delays in surgery and their impact on survival in papillary thyroid cancer (PTC) is unclear. We sought to investigate the association between time to surgery and survival in patients with PTC. Methods A total of 8170 Medicare beneficiaries with PTC who underwent thyroidectomy were identified within the Surveillance, Epidemiology, and End Results-Medicare linked data files between 1999 and 2018. Disease-specific survival (DSS) and overall survival (OS) were estimated using Kaplan-Meir analysis, and Cox proportional hazards models were specified to estimate the association between time to surgery and survival. Results Among 8170 patients with PTC, mean age 69.3 (SD+/- 11.4), 89.8% had surgery within the first 90 days, 7.8% had surgery 91 to 180 days from diagnosis, and 2.4% had surgery after 180 days. Increasing time to surgery was associated with increased mortality for OS in the >180-day group [adjusted hazard ratio (aHR) 1.24; 95% CI, 1.01-1.53]. Moreover, on stratification by summary stage, those with localized disease in the 91- to 180-day group increased risk by 25% (aHR 1.25; 95%CI, 1.05-1.51), and delaying over 180 days increased risk by 61% (aHR 1.61; 95%CI, 1.19-2.18) in OS. Those with localized disease in the >180-day group had almost 4 times the estimated rate of DSS mortality (aHR3.51; 95%CI, 1.68-7.32). When stratified by T stage, those with T2 disease in the >180 days group had double the estimated rate of all-cause mortality (aHR 2.0; 95% CI, 1.1-3.3) and almost triple the estimated rate of disease-specific mortality (aHR 2.7; 95% CI, 1.05-6.8). Conclusions Delays in surgery for PTC may impact OS and DSS in localized disease, prior to nodal metastasis.