CD4 and neoplasm: Our previous study on IHC analysis of OPLs showed that the tumor microenvironment is a Th1-dominated milieu, where cells expressing chemokine receptor CXCR3 and CCR5, typically expressed on CD4+ T helper type 1 (Th1), CD8+ cytotoxic T lymphocytes (CTLs), and natural killer (NK) cells, are observed in OPLs [8].