This finding may be explained by the liver's role as a tolerogenic organ.31, 32, 33 Tumeh et al (2017) found that melanoma and lung cancer patients with liver metastases treated with anti‐PD‐1 agents had decreased CD8+T‐cell density at the liver metastatic margin and furthermore that these patients had decreased response rate and shortened PFS.34 The density of CD8+T‐cells in the liver may, therefore, affect response to ICI. This evidence concerns the gene CD8A and melanoma.