CD4 and thyroid cancer: The results showed that the infiltration degree of effect memory CD4 T cells, immature dendritic cells, plasmacytoid dendritic cells and natural killer cells in the high-risk group of thyroid cancer patients decreased, while the infiltration degree of activated B cells, eosinophils and mast cells increased, thus indicating that our eight-gene prognostic model may be a predictor of immune responses in thyroid cancer.