Neoadjuvant Chemo-Immunotherapy in Very Advanced (T4) Head and Neck Squamous Cell Carcinoma: A Real-World Study

Aims This study aimed to evaluate the efficacy and safety of neoadjuvant chemo-immunotherapy in patients with very advanced (T4) head and neck squamous cell carcinoma (HNSCC), while also exploring outcomes in the specific subgroup of T4b stage patients. Methods We retrospectively analyzed 87 initially diagnosed T4 HNSCC patients who received neoadjuvant chemo-immunotherapy between April 2020 and March 2023 at the Sun Yat-sen University Cancer Center. The primary endpoint of this study was overall survival (OS) and the secondary endpoint was event-free survival (EFS). Results The overall response rate (ORR) after neoadjuvant chemo-immunotherapy was 75.8%, with 10.3% achieving a complete response (CR) and 69.0% achieving a partial response (PR). The 1-year and 3-year OS rates for the total cohort were 90.8% and 66.7%, while the 1-year and 3-year EFS rates were 81.3% and 56.0%, respectively. Cox regression analyses indicated that receiving 3–4 cycles of treatment, pretreatment clinical N0 stage, and favorable radiographic responses (CR and PR) were significantly associated with improved OS and EFS. Remarkably, among the 12 T4b patients, 11 (91.7%) achieved a PR while one experienced stable disease (SD). Furthermore, 8 T4b patients (66.7%) were converted to resectable status, and 5 of them underwent surgical treatment following neoadjuvant therapy. Grade 3 or 4 treatment-related adverse events occurred in 7 patients (8.0%). Conclusion Neoadjuvant chemo-immunotherapy demonstrates promising survival outcomes and manageable toxicity in very advanced T4 HNSCC patients, highlighting its potential as an effective treatment strategy for this challenging subgroup.