IDO1 and uterine cervix neoplasm: This cordon around the metastases might be caused by the presence of immunosuppressive factors such as PD-L1, IDO, IL-6 and Prostaglandin-E2 (PGE2) [2, 25], or extracellular matrix components (e.g. versican) [26] shown to be expressed by primary cervical tumor cells, leading to immunosuppressive cell subset accrual and preventing antitumor cell subsets to enter the tumor area.