PDCD1 and neoplasm: Using histopathological methods, the biomarkers of CD8+ for cytotoxic T cells, CD4+ for T-helper cells, CD68+ for macrophages, FOXP3+ for regulatory T cells, programmed cell death protein 1 (PD-1), and programmed cell death-ligand 1 (PD-L1) were analyzed in primary OV tumor slices for in vivo and in 3 day cultured samples.