Analysis of immediate 503 thyroid carcinoma deaths: trend of single institution in 2005-2024.

[BACKGROUND] This study aimed to investigate the changes in histological types and causes of death associated with thyroid carcinoma (TC) before and after the introduction of systemic drug therapy.

[METHODS] The records of 503 deceased patients treated for TC and with death from TC between January 2005 and June 2024 were reviewed in this retrospective cohort study. Multivariate logistic regression was applied to assess whether the number of patients with anaplastic TC (ATC) at diagnosis and the number of local-related deaths changed before and after the introduction of lenvatinib (i.e. 2005-2014 vs 2015-2024).

[RESULTS] Of the 503 patients, 157 (31%) had ATC, 253 (50%) had papillary TC (PTC), 67 (13%) had follicular TC (FTC), 17 (3%) had poorly differentiated TC, and nine (2%) had medullary TC. Respiratory insufficiency was the most common fatal condition, occurring in 192 cases (38%), followed by local-related death in 98 cases (19%) and brain-related conditions in 22 cases (4%). We found no difference in the frequency of patients with ATC at diagnosis (32 vs 30%; P-value = 0.772) and the frequency of local-related deaths (19 vs 20%; P-value = 0.736) between 2005-2014 and 2015-2024. These findings were supported by multivariate logistic regression models that adjusted for other covariates (adjusted P-value = 0.436 and 0.353, respectively).

[CONCLUSIONS] ATC, including anaplastic transformation from PTC and FTC, still accounts for approximately 40% of thyroid cancer deaths after the introduction of systemic drug therapy. Respiratory insufficiency is the most common immediate cause of death.