Neutrophil-to-Lymphocyte Ratio as a Prognostic Factor of Survival Outcomes in Head and Neck Squamous Cell Carcinoma Receiving Neoadjuvant Immunotherapy.

[PURPOSE] The neutrophil-to-lymphocyte ratio (NLR) is a prognostic marker in cancers treated with immune checkpoint inhibitors (ICI), reflecting the link between inflammation and cancer immune response. This study examines NLR's prognostic value in head and neck squamous cell carcinoma (HNSCC) patients receiving neoadjuvant ICI therapy, focusing on its potential as an independent predictor of overall survival (OS) and disease-free survival (DFS).

[METHODS] We conducted a retrospective cohort study including three neoadjuvant trials: durvalumab ± metformin, nivolumab ± tadalafil, or nivolumab ± BMS-986205 from 2017 to 2022. Pre-treatment NLR was calculated using absolute neutrophil and absolute lymphocyte counts obtained before neoadjuvant ICI initiation. The optimal pre-treatment NLR cut-off was identified using receiver operating characteristic (ROC) curve analysis. OS and DFS were assessed using Kaplan-Meier and multivariable Cox proportional hazards regression models.

[RESULTS] A total of 97 patients met inclusion criteria. NLR < 4.14 was associated with improved overall survival (HR 0.07, 95% CI 0.01-0.30, p < 0.001) and DFS (HR 0.21, 95% CI 0.08-0.54, p = 0.001) compared to NLR ≥ 4.14. NLR < 4.14 remained independently associated with improved OS (HR 0.14, 95% CI 0.02-0.78, p = 0.025) and DFS (HR 0.25, 95% CI 0.07-0.87, p = 0.030) on multivariable Cox regression. The survival benefit of NLR < 4.14 persisted after sub-stratification for p16 status, ICI pathologic response status, and ICI trial.

[CONCLUSION] Low NLR was independently associated with improved OS and DFS among patients with HNSCC who received neoadjuvant ICI. These findings suggest the potential utility of the NLR in improving patient selection.