Wang BC, et al. - In patients with head and neck cancer, researchers evaluated the benefit and risk of programmed cell death-1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors. To find potentially eligible studies up to May 30, 2019, the PubMed, Cochrane Library, EMBASE and Web of Science databases were systematically searched. According to this systematic review and meta-analysis, in patients with recurrent or metastatic head and neck cancer, PD-1 inhibitors prolonged OS compared with standard-of-care therapy. In the treatment of PD-1/PD-L1 inhibitors, human papillomavirus positive patients were superior to HPV negative patients. Aspartate aminotransferase increased was most common for grade ≥ 3 treatment-related adverse events, followed by fatigue, pneumonia, and diarrhea. To verify the results, more phase III randomized controlled trials are warranted.