The results of TTFields combined with immune checkpoint inhibitor anti-PD1 intervention in an in situ Lewis lung cancer mouse model showed that the tumor volume inhibition effect of the combined treatment was significantly higher than that of the single treatment group, and the proportions of macrophages, DCs, CD8+ T cells, and CD4+ T cells in the tumor microenvironment of mice receiving the combined treatment were all upregulated [30]. Here, CD4 is linked to neoplasm.