We identified a subgroup treated with an anti-PD1 agent and VEGFR inhibitor in combination, in which CRC patients with LM are much more likely to resist the therapy (n=8 studies, OR 0.23, 95%CI, 0.10–0.54, I2=0%, p=0.63) (Fig. 4A) [42–49]. This evidence concerns the gene PDCD1 and colorectal carcinoma.