SPDL1 and hepatocellular carcinoma: Higher levels of sPD-1 were found in HBV (hepatitis B virus)-related hepatocarcinoma (HCC) due to the activation of immune response against both HBV and tumor, and are associated with HCC patients’ OS [33], while in patients with pancreatic adenocarcinoma, increased levels of both sPD-1 and sPD-L1 were associated with worst survival [34].