Neoadjuvant Immunotherapy in Resectable HNSCC: An Updated Systematic Review and Meta-analysis

Immunotherapy is a recently recognised FDA-approved treatment for R/M HNSCC. Our goal is to explore the safety profile and the efficacy of immunotherapy in the neoadjuvant setting before surgery in mucosal head and neck cancer.

Three electronic databases had been systematically searched through March 2024. Demographic and tumour characteristics were extracted. Primary outcomes obtained were disease-free survival (DFS), progression-free survival (PFS), overall survival (OS), complete pathological response (cPR), which was defined as no residual tumour, and major pathological response (MPR), which as defined as <10% residual viable tumour. Safety outcomes examined were grade 3 and above adverse event, median time to surgery, delays to surgery, and death related to neoadjuvant treatment.

A total of 459 patients from 15 studies were included in the analysis. The pooled estimate of cPR for all the studies was 14.9% (95% confidence interval [CI] 8.0-26.2). Subgroup analysis showed chemoimmunotherapy had a higher cPR 30.1% (95% CI 22.8-38.62) compared with immunotherapy alone 1.4% (95% CI 0.3-5.2). There was no treatment-related death. Chemoimmunotherapy had a higher pooled estimate of adverse events 22.9% (95% CI 11.0-41.5) compared with immunotherapy alone 8.5% (95% CI 2.6-24.3). Subgroup analysis demonstrated that chemoimmunotherapy had a higher DFS compared with immunotherapy alone: 89.8% (95% CI 81.4-94.7) versus 80.44% (95% CI 73.9-85.7), respectively. Neoadjuvant immunoradiotherapy had conflicting results.

Neoadjuvant immunotherapy was well tolerated. Neoadjuvant chemoimmunotherapy may be more effective in treating LAHNSCC over immunotherapy alone; however, TRAEs were higher.