In other studies, peripheral blood factors, such as low serum lactate dehydrogenase and relative lymphocyte count, were shown to be associated with better outcomes for patients with melanoma treated with pembrolizumab or ipilimumab, a PD-1 monoclonal antibody and a CTLA4 monoclonal antibody, respectively [20, 21]. This evidence concerns the gene CTLA4 and melanoma.