Meta analysis results showed that the incidence of grade 3–4 immunotoxicity was approximately 10–24% with programmed cell death protein 1( PD-1) or cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) monotherapy [5, 6], and reached 59% with combined immunotherapy [7]. The gene discussed is CTLA4; the disease is immune system toxicity.