Time to Surgery and Thyroid Cancer Survival in the United States.

Abstract

Longer time to surgery worsens survival in multiple malignancies, including lung, colorectal, and breast cancers, but limited data exist for well-differentiated thyroid cancer. We sought to investigate the impact of time to surgery on overall survival in patients with papillary thyroid cancer. In a retrospective cohort study of the National Cancer Database, we used Cox proportional hazard models to investigate overall survival as a function of time between diagnosis and surgery for adults with papillary thyroid cancer, adjusting for demographic, patient, and cancer-related variables. Time to surgery was investigated both as a continuous variable and as intervals of 0-90 days, 90-180 days, and > 180 days. Subgroup analyses were conducted by T stage. Overall, 103,812 adults with papillary thyroid cancer were included from 2004 to 2016. Median follow-up was 55.2 months (interquartile range 28.4-89.5). Increasing time to surgery was associated with increased mortality: delaying by 91-180 days increased the risk by 30% (adjusted hazard ratio [aHR] 1.30, 95% CI 1.19-1.43) and delaying by over 180 days increased the risk by 94% (aHR 1.94, 95% CI 1.68-2.24). Five-year overall survival was 95.7% for 0-90 days, 93.0% for 91-180 days, and 87.9% for over 180 days. On subgroup analysis, increasing delay was associated with worse overall survival for T1, T2, and T3 tumors, but not T4 tumors. Increasing time to surgery in papillary thyroid cancer is associated with reduced overall survival. Further research is necessary to assess the impact of surgical delay on disease-specific survival.