Renal cell carcinoma (RCC) is characterized by insidious onset, lack of early typical clinical manifestations, metastasis or advanced stage at diagnosis in most patients and poor efficacy of radical nephrectomy. In recent years, with the broadly application of targeted therapies in tumors, the postoperative recurrence and mortality rates have been greatly reduced. However, there is a lack of evidence for the efficacy and safety of clinical treatment due to the existence of certain adverse effects and complications.

To systematically review the efficacy and safety of programmed death-1 (PD-1) /programmed death-1 ligand (PD-L1) inhibitors in the treatment of RCC.

CNKI, Wanfang Data, VIP, PubMed, Web of Science, Embase, Cochrane Library, Clinical Trials and other English databases were searched by computer and manually for the randomized controlled trials of PD-1/PD-L1 inhibitors for RCC from the inception to 2022-09-30. Two researchers independently extracted and collated the data, evaluated the quality of the included literature according to Cochrane 5.3 manual criteria, and performed meta-analysis using RevMan 5.4 software.

A total of 11 papers were finally included, involving 7 895 study subjects with 3 936 cases in the trial group and 3 959 cases in the control group. Meta-analysis results showed that the overall survival (OS) and progression-free survival (PFS) were better in the trial group than in the control group〔HR=0.87, 95%CI (0.84, 0.90), P<0.000 01; HR=0.85, 95%CI (0.78, 0.92), P<0.000 1〕; the objective response rate (ORR), partial response rate (PR), complete response rate (CR), and disease-control rate (DCR) were higher in the trial group than in the control group〔RR=1.72, 95%CI (1.39, 2.12), P<0.000 01; RR=1.56, 95%CI (1.20, 2.01), P=0.000 7; RR=3.05, 95%CI (2.39, 3.09), P<0.000 01; RR=1.12, 95%CI (1.05, 1.20), P=0.000 5〕; the rate of stable disease (SD) was lower in the trial group than in the control group〔RR=0.66, 95%CI (0.62, 0.72), P<0.000 01〕. The differences were not statistically significant when comparing the rate of PD, total rate of adverse events (AEs), rates of grade Ⅰ-Ⅱ adverse events and grade Ⅲ-Ⅴ adverse events between the trial and control groups〔RR=0.73, 95%CI (0.53, 0.99), P=0.05; RR=1.01, 95%CI (0.89, 1.04), P=0.60; RR=1.02, 95%CI (0.88, 1.17), P=0.82; RR=1.02, 95%CI (0.88, 1.19), P=0.80〕. Egger's tests resulted in P>0.05, indicating no significant publication bias among studies.

PD-1/PD-L1 inhibitors for RCC can significantly improve and enhance OS, PFS, ORR, CR, PR and DCR in patients without increasing the incidence of adverse effects in terms of safety, thus confirming the superiority of PD-1/PD-L1 inhibitors for RCC in terms of clinical efficacy and safety.