CD4 and esophageal squamous cell carcinoma: It can be clearly seen from Figure 4(a) that the numbers of Teff cells (CD3 and CD8), Treg cells (CD4 and FOXP3), and neutrophils (CD68 and CD163) positive immunofluorescence staining (yellow) cells in group B ESCC tissue were greatly more than those in group A. Therefore, 10 staining fields were randomly selected to count the positive staining cells, and the average was calculated and statistically compared.