CTLA4 and melanoma: A recent retrospective study with a larger sample size also investigated the efficacy of PD-1 plus CTLA-4 for Japanese patients with advanced AM and demonstrated that the efficacy of PD-1 plus CTLA-4 was not superior to that of PD-1 monotherapy for palm and sole melanoma (PSM), although the efficacy of PD-1 plus CTLA-4 was potentially better than that of PD-1 alone for NAM (22).