We used immunohistochemistry to evaluate the presence of tumor-infiltrating FoxP3+ T-cells and CTLA-4+ cells in four distinct histological compartments (tumor parenchyma and stroma at the tumor center, and parenchyma and stroma at the invasive front) and assessed the association between the prevalence of these cells and the histopathological status of 137 patients with OSCC. This evidence concerns the gene CTLA4 and neoplasm.