Recently, soluble forms of PD-L1 (sPD-L1), which include exosomal PD-L1 (exo-PD-L1) and secreted splice variants (secPD-L1), have been identified in the peripheral blood and proven to inhibit the functions of T cells, meditate tumor evasion, and promote tumor progression [18]. The gene discussed is SPDL1; the disease is neoplasm.