The stacked bar chart of CD3, CD4 and CD8 staining in 20 patients with PTC-WO and 20 patients with PTC-W showed that the numbers of CD3+, CD4+ and CD8+ T cells of tumor and normal samples in PTC-W were significantly higher than those in PTC-WO (Figures 1D, E). Here, CD4 is linked to neoplasm.