PDCD1 and neoplasm: PD-1 is expressed on activated T cells,40 and PD-L1, expressed by a wide range of cells, for example, T-regulatory cells and tumor cells, is upregulated by inflammatory signaling.41 Furthermore, measurements of the PD-1/PD-L1 pathway provide independent information in addition to TILs.26 For this reason, we used high TILs combined with the expression of PD-1 or PD-L1 to characterize an active immune response.