Background: Thyroid disorders, including thyroid cancer and autoimmune thyroid diseases, have been closely associated with inflammation.
Objective: This study aims to investigate the role of inflammation in thyroid disease by assessing serum cytokine levels in patients with malignant and benign thyroid conditions.
Methods: Serum levels of ten interleukins (IL-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12 and IL-13) were quantitatively determined in 20 patients with thyroid cancer, 38 patients with benign thyroid disease and 50 healthy controls by multiplex technology.
Results: Serum IL-1β, IL-2, IL-4, IL-5 and IL-6 levels were strongly associated with each other. IL-10 and IL-12 correlated with IL-1β, IL-5, IL-6, and with each other. Age was inversely correlated with serum levels of IL-2, IL-4 and IL-13. A positive correlation between T3 and IL-13 levels was also observed. Significantly higher levels of IL-6, IL-7, IL-10 and IL-13, as well as significantly lower levels of IL-8 were observed in patients with benign and malignant thyroid disease compared to controls. The combination of IL-13 and IL-8 in a two-marker panel was highly efficient in discriminating thyroid disorders (AUC 0.90).
Conclusions: Malignant and benign thyroid conditions are associated with altered expression levels of interleukins, supporting the association between thyroid disease and underlying inflammatory processes.