Immunotherapy such as anti-PD1 (programmed cell death protein 1) anti-PD-L1 (programmed cell death protein—ligand 1) or CTLA-4 (cytotoxic T-lymphocyte-associated protein 4) therapy is often applied successfully in cutaneous melanoma, but has limited success in UM [45]. Here, CTLA4 is linked to cutaneous melanoma.