CD4 and secondary neoplasm: Notably, the triple therapy also showed an enhancement in the expression of nFas and nFasL in CD8 and CD4 T cells in the primary tumor and secondary tumors, as compared to mice treated with XRT and anti-PD1 therapy, indicating a great turnover of these cells in which the promotion of programmed cell death may facilitate the replacement of unstable or exhausted T cells with healthier and more effective counterparts (Fig. 4 Primary and Secondary Tumors A).