Non-infectious encephalitis/myelitis was reported more with anti-PD-1/PD-L1 than with anti-CTLA-4 (ROR 2.5, 95% CI 1.6–3.9) and with combination therapy compared with monotherapy (ROR 2.0, 95% CI 1.4–2.7). This evidence concerns the gene CTLA4 and myelitis.