Second, differences in the clinical response to imatinib mesylate are expected among the study participants due to the diversity of mutational status of KIT gene as reported in the four phase II trials of imatinib mesylate monotherapy for melanoma; ORR of melanoma patients with KIT mutations in exon 11 or 13 was 24.4% while that for the patients with alterations in other gene loci was 19.4%.[17,18] Third, this study uses a single arm design, and therefore does not demonstrate the superiority of imatinib mesylate and pembrolizumab combination over imatinib mesylate monotherapy. This evidence concerns the gene KIT and melanoma.