The incidence of pseudoprogression according to the agent types were also analyzed: the pooled incidence in the studies of PD-1/PD-L1 inhibitor monotherapy was 5.7% (5.6% for PD-1 and 6.8% for PD-L1), whereas one study of melanoma that used a CTLA-4 inhibitor showed higher incidence of pseudoprogression (9.7%). The gene discussed is PDCD1; the disease is melanoma.