CD8A and neoplasm: At day 7, we observed small, but not statistically significant, increases in Pentamer+ CD8+ T cells with all treatments (Figure 3B), indicating that ATRi QDx3 plus RT generated a tumor antigen–specific CD8+ T cell expansion at day 9 that is caused by neither rebound proliferation following ATRi QDx3 nor a simple delay in antigen-specific CD8+ T cell expansion triggered by RT alone at an earlier time point.