In another meta-analysis of 9 articles that included 217 HPD patients and 1519 cancer patients treated with anti-PD-1/PD-L1 therapy, positive PD-L1 expression on tumor cells was inversely correlated with HPD.[18] PD-L1 expression on tumor cells in our case was negative, which is consistent with the report. This evidence concerns the gene CD274 and neoplasm.