To date, several immune checkpoint inhibitors (ICIs) have been approved for tumor treatment, including PD-1 inhibitors (nivolumab, pembrolizumab, cemiplimab), PD-L1 inhibitors (avelumab, durvalumab, atezolizumab), and CTLA-4 inhibitors (ipilimumab). This evidence concerns the gene CTLA4 and neoplasm.