Neutrophil-to-Lymphocyte Ratio and Pembrolizumab Outcomes in Oral Cavity Squamous Cell Carcinoma.

Abstract

Objective: To determine the relationship between pretreatment neutrophil-to-lymphocyte ratio (NLR) and 6-month progression-free survival (PFS)/2-year overall survival (OS) among patients with recurrent or metastatic (R/M) oral cavity cancer on pembrolizumab.

Study design: This study was a retrospective, observational study performed at a tertiary care academic center.

Setting: Participants included patients with oral cavity squamous cell carcinoma (OCSCC) who began pembrolizumab treatment at the University of California, San Francisco between May 2016 and May 2022.

Methods: The primary outcome was a 6-month PFS. The secondary outcome was a 2-year OS. NLR was treated as a continuous variable. Disease progression was determined using radiographic criteria, adopted from the Response Evaluation Criteria in Solid Tumors.

Results: Fifty-two patients with OCSCC were included. Immune checkpoint inhibitor (ICI) indication was recurrence/metastasis for all patients. The median pretreatment NLR was 5.7 (interquartile range: 3.6-7.6). Twenty-seven (55%) patients received pembrolizumab alone. Of those receiving treatment for R/M prior to ICI, 9 (18%) received salvage surgery and adjuvant therapy, 2 (4%) received chemotherapy alone, 1 (2%) received chemoradiation, and 10 (20%) received salvage surgery. Nineteen (36.5%) patients had distant metastases at the start of ICI. Six-month PFS was 46%. Two-year OS was 44%. NLR was independently associated with 6-month PFS [hazard ratio, HR: 1.05 (95% confidence interval, CI: 1.01-1.11), P = .028] and 2-year OS [HR: 1.12 (95% CI: 1.05-1.20), P < .001].

Conclusion: Higher pretreatment NLR was associated with poorer 6-month PFS and 2-year OS in OCSCC patients treated with pembrolizumab.