Korean Study Sheds Light on Well-Differentiated Thyroid Cancer
Posted: Monday, October 12, 2020
Research published in the journal Cancers outlined the clinical course and causes of death in patients with well-differentiated thyroid cancer, a disease typically with a low overall mortality rate. Jae Hoon Chung, MD, PhD, of the Sungkyunkwan University School of Medicine, Korea, and colleagues observed that the causes of death recorded in this study differed by the metastatic site. In contrast, overall survival tended to be dependent on the clinical course.
The study included 592 patients with well-differentiated thyroid cancer who died between 1996 and 2018, 79 of whom were evaluable. That group was categorized by clinical course: inoperable at the time of diagnosis, distant metastasis observed at the time of diagnosis, distant metastasis identified during follow-up treatment, and locoregional disease.
Overall survival differed substantially by clinical course, with those who had late distant metastasis experiencing the longest survival, followed by those with locoregional disease, initial distant metastasis, and inoperable disease. Subgroups of patients with either papillary thyroid carcinoma or follicular thyroid carcinoma within the group with initial distant metastasis experienced comparable rates of overall survival (P = .83).
Among those experiencing metastasis, patients who had brain metastasis (13.3%) had the poorest prognosis. In patients with papillary thyroid carcinoma, the most common metastasis was to the lungs (55.6%), and the leading causes of death were respiratory failure (32.3%) and airway obstruction (30.6%). The most common metastasis in patients with follicular thyroid carcinoma was to the bone (46.7%); for that group, complications related to bone metastasis-induced immobilization (35.3%) were the leading cause of death. Well-differentiated thyroid cancer itself was not the leading cause of death for participants in this study.
Disclosure: The study authors reported no conflicts of interest.