We report a rare case of an 84-year-old female patient with advanced gastric cancer who developed recurrent immune-related hematologic toxicities—including immune checkpoint inhibitor-induced autoimmune hemolytic anemia and thrombocytopenia—following sequential treatment with three immune checkpoint inhibitors targeting distinct pathways: the PD-1 inhibitor sintilimab, the PD-1/CTLA-4 bispecific antibody cadonilimab, and the PD-L1 inhibitor ivonescimab. The gene discussed is CTLA4; the disease is gastric cancer.