Hypoproteinemia being a manifestation of immunotherapy-related liver dysfunction

Immunotherapy has changed the pattern of treatment in cancer. The interaction between programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) inhibits the activation of T cells, and PD-1/PD-L1 inhibitors can increase the immune response to cancer cells by inducing the immune cells, which has become an important clinical method to treat cancer. However, the alteration in the activation of T cells might lead to misidentification between the body's own cells and tumor cells and induce immune-related adverse events (IRAEs), such as pneumonitis, liver dysfunction, rash, colitis, nephritis, and endocrinopathies. And the IRAEs might lead to serious consequences. Studies have reported that PD-1/PD-L1 inhibitor-related hepatotoxicity is one of these adverse events. Most of the studies reported that hepatitis resulting from PD-1 inhibitor was manifested as elevated liver enzymes and bilirubin. Quite a few patients experienced lower degree of hepatotoxicity treated with checkpoint inhibitors, which indicated that it was necessary to focus on immunotherapy-related liver dysfunction. Here, we report a case of immunotherapy-related liver dysfunction with hypoproteinemia as the first manifestation under the treatment of PD-1 inhibitors combined with chemotherapy. This case suggests that hypoproteinemia was one of the manifestations of immunotherapy-related liver dysfunction, which helps us better understand the immunotherapy-related disease.