T cell infiltrates from areas of PCa and BPH tissue samples. Legend: (A) Microscopic appearance of benign prostatic hyperplasia, usual staining (×20); (B) prostate adenocarcinoma, usual staining, Gleason score 3 + 4 (×20); (C) CD4-positive peritumoral lymphocytes, more than 50 cells/HPF, prostate adenocarcinoma, Gleason score 3 + 4 (×20); (D) CD4-intensely positive in the peritumoral stroma, more than 50 cells/HPF, prostate adenocarcinoma, Gleason score 4 + 5 (×20); (E) CD3-positive (adenocarcinoma, Gleason score 4 + 5), less than 50 cells /HPF (×20); (F) CD8-positive (adenocarcinoma, Gleason score 4 + 4), more than 50 cells /HPF (×20).