Efficacy of neoadjuvant immunotherapy in head and neck squamous carcinoma (HNSCC): A systematic review and meta-analysis.

Abstract

e18012 Background: Head and neck squamous cell carcinoma (HNSCC) is a significant global health burden with limited treatment options in advanced stages. Neoadjuvant immunotherapy has emerged as a promising strategy to improve outcomes. However, the overall efficacy remains to be fully elucidated. Here, we present a systematic review and meta-analysis to comprehensively evaluate the efficacy of neoadjuvant immunotherapy in patients with HNSCC. Methods: A comprehensive literature search of PubMed, EMBASE, and Cochrane databases was performed through December 30, 2024. A risk of bias assessment was conducted to evaluate study quality. Using Stata v.18.0, we performed a meta-analysis to calculate the pooled objective response rate (ORR), pathological complete response (pCR), and disease control rate (DCR), with corresponding 95% confidence intervals (CIs). Results: The initial search identified 1221 potentially relevant articles. After excluding duplicates and studies not meeting inclusion criteria, 20 clinical trials investigating neoadjuvant immunotherapy in HNSCC were included. Neoadjuvant immunotherapy demonstrated a pooled pathological complete response (pCR) rate of 15% (95% CI: 6.9-27.2), an objective response rate (ORR) of 32% (95% CI: 14-51.0), and a disease control rate (DCR) of 88.3% (95% CI: 78.1-95.7) in HNSCC patients. Comparative analysis revealed a significantly higher disease control rate (DCR) with control compared to immunotherapy (OR = 4.50, 95% CI: 2.62-7.73, P < 0.001, I 2 =58%). While immunotherapy was also associated with a higher ORR compared to control, this difference did not reach statistical significance (OR=0.55, 95% CI: 0.26-1.18, P = 0.12, I 2 =83%). However, immunotherapy did result in a statistically significant improvement in pCR versus control (OR = 0.25, 95% CI: 0.14-0.46, P < 0.001, I2=74%). Furthermore, safety analysis indicated a significantly lower incidence of grade ≥3 adverse events in the immunotherapy group compared to control (OR = 0.14, 95% CI: 0.07-0.3, P < 0.001, I 2 =79%). Conclusions: The overall findings suggest that neoadjuvant immunotherapy yields promising clinical activity in HNSCC, evidenced by notable pCR, DCR and ORR rates. Importantly, immunotherapy significantly improved DCR and pCR, while also demonstrating a favorable safety profile with fewer high-grade adverse events compared to control. Further large-scale randomized controlled trials are warranted to confirm these findings and to identify patient subgroups that may derive the most benefit from this approach.