Further studies are needed to evaluate the value of [18F]FDG-PET for monitoring or prediction of responses to anti-PD-1 therapies; for example, by using highly immunogenic mouse models, considering the tumor central area with less immune cell infiltration and the invasive margin with high immune cell infiltration separately, and conducting long-term experiments and combining [18F]FDG-PET and immune-PET imaging. This evidence concerns the gene PDCD1 and neoplasm.