Real-world efficacy of anti-PD-1 antibody or combined anti-PD-1 plus anti-CTLA-4 antibodies, with or without radiotherapy, in advanced mucosal melanoma patients: A retrospective, multicenter study

•Immune checkpoint inhibitors (ICIs) have a low efficacy for mucosal melanoma (MUM).•Combined ICI and radiotherapy treatment (RT) for MUM was investigated.•Objective response rate and survival were used to assess efficacy.•ICI treatment alone and combined with RT were not significantly different.•ICI + RT may improve local control at the irradiation site.