Combined Positive Score and Cisplatin Sensitivity Are Prognostic Factors for Response to Nivolumab Therapy for Recurrent Metastatic Squamous Cell Carcinoma of the Head and Neck.

BACKGROUND

Recurrent or metastatic squamous cell carcinoma of the head and neck (R/MHNSCC) is a challenging malignancy with a poor prognosis and limited treatment options. Nivolumab, an immune checkpoint inhibitor (ICI) targeting the programmed cell death/programmed cell death ligand 1 (PD-1/PD-L1) pathway, has emerged as a promising therapy for these patients. However, identifying biomarkers predictive of response to nivolumab remains critical for optimizing treatment strategies. Previous studies have suggested that PD-L1 expression, as determined by the Combined Positive Score (CPS) and other clinical factors, may influence treatment outcome. This study aims to retrospectively examine whether CPS can be a biomarker by staining PD-L1 with 22 C3 antibody in R/MHNSCC patients treated with nivolumab.

METHODS

This retrospective study reviewed the medical records of R/MHNSCC patients treated with ICIs at Tokai University Hospital from April 2017 to December 2022. We examined the relationship between response rate to ICI therapy, PD-L1 staining, biomarkers, and survival. Statistical analyses included -test, chi-square test, and Cox regression.

RESULTS

This study included 92 nivolumab-treated patients. Combined Positive Score was evaluable in 53 of these patients. Patients with a CPS of 15 or higher had better progression-free survival (PFS) ( = .0171), with a median PFS) of 13 months. In the Various Definitions analysis, cisplatin-sensitive patients also had good PFS ( = .0295). The cisplatin-sensitive patient population with a CPS of 15 or higher had the best PFS, with a median of 14 months ( = .006). There was no significant difference in overall survival (OS) by CPS value. Immune-related adverse events did not affect OS or PFS.

CONCLUSIONS

CPS ⩾ 15 and cisplatin sensitivity are promising prognostic markers for nivolumab therapy in R/MHNSCC. Considering these biomarkers in patient selection could maximize the therapeutic benefits of nivolumab. This finding may help to optimize ICI therapy strategies.