It is noteworthy, however, that we did observe a significant increase in frequency of Ki67+ CD8 T cells expressing PD-1 after onset of therapy in all BOR groups (Additional file 1: Figure S5) and that there was a positive correlation between frequency of Ki67+ within PD1+CD8 T cells and pre-treatment tumor volume of target lesions in NSCLC patient. Here, CD8A is linked to neoplasm.