B. N. Titanji1,2, M. Earley1, E. Kebebew1 1Stanford University, Department Of Surgery, Palo Alto, CA, USA 2Meharry Medical College, School Of Medicine, Nashville, TN, USA
Introduction: Anaplastic thyroid cancer (ATC) has one of the highest mortality rates of all human malignancies, accounting for 40% of all thyroid cancer deaths. Despite multimodal treatment, ATC still has a reported median survival period of 6 months. The first ever drug therapy for ATC was approved in 2018 for patients with the BRAF mutation (present in 50% of ATC cases). In this study, we sought to investigate if the risk of mortality decreased over time due to the approval of new treatments and use of multimodal treatments.
Methods: 874 patients in the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) database that were diagnosed with ATC from 1990 to 2020 were included in this study. Cox proportional hazards models were used to assess the change in two-year survival over time and to identify characteristics associated with survival. Overall survival (OS) and cancer specific survival (CSS) were both evaluated. All multivariable models included age, ATC subtype, and if any treatment was administered. Additional covariates were included based on their significance in univariable models.
Results: Among the 874 patients included in this analysis, the all-cause mortality rate within 2 years of diagnosis was 86% and the cancer-attributable mortality rate was 81%. For every 3-year increase in diagnosis year from 1990 to 2020, there was no significant change in the risk of cancer-specific mortality (adjusted hazard ratio (95% CI): 0.97 (0.94, 1.01), p=0.12). Patients who received treatment (surgery, chemotherapy, or radiation) had a decreased risk of cancer-specific mortality (adjusted HR (95% CI): 0.41 (0.31, 0.54), p<0.0001). Compared to patients diagnosed with localized cancer, those with unstaged or distant cancer have an increased risk of mortality.
Conclusion: We observed no significant change in mortality after adjusting for confounders by year of diagnosis. Though receiving treatment decreases risk of mortality, more effective treatments are needed in the future to increase survival time in patients with ATC.