Neoadjuvant PD-1/PD-L1 inhibitors combined with chemotherapy had a higher ORR than mono-immunotherapy in untreated HNSCC: Meta-analysis

HNSCC is one of the most common types of cancer worldwide and immune checkpoint inhibitor has shown favorable therapeutic effect in R/M HNSC. However, the application of immunotherapy in untreated HNSCC still needs to be discovered since most R/M HNSCC patients have been treated before and their drug susceptibility and immune tumor microenvironment have changed. This meta-analysis tries to compare immunotherapy and immunochemotherapy in untreated HNSCC and give a reference for clinic application. Methods: Electronic databases, including PubMed, Embase, and Web of Science, were systematically searched from inception through August 31, 2022. The primary outcomes were efficacy, evaluated by objective response rate, 1-year OS and 1-year PFS, and safety, evaluated by grade 3–4 adverse reaction rate. Results: A total of 1092 patients from twenty-four studies were included, 282 (25.8%) of which had ORR reported. The average ORR was 37% (95%CI = 26%-49%). Immunochemotherapy could have higher ORR than immunotherapy patients (ORR: 61% vs 22%), and favorable 1-year overall survival from PD-L1 inhibitor (OS = 84%, 95%CI 76%-93%). Radiotherapy after neoadjuvant immunotherapy was equal with the other treatments like chemotherapy and surgery (84% vs 88%, subgroup df p = 0.7). There was no apparent difference between immunotherapy and immunochemotherapy (32% vs 42%, subgroup df p = 0.60). Conclusion: HNSCC patients could benefit more from neoadjuvant immunochemotherapy.