PDCD1 and neoplasm: FNA and tumor samples are distinguished by low abundance of CD66b+ granulocytes, higher expression of PD-L1 and PD-L2 suppressive checkpoint co-receptors on CD33+ and CD66b+ cells, and higher expression of PD-1, TIM-3 and LAG-3 inhibitory receptors on CD3+ T cells (upper right quadrant of figure, yellow enrichment).