Novel biomarkers for head and neck squamous cell carcinoma: A retrospective study.

Abstract

e18010 Background: PDL-1 and tumor mutation burden are only useful to select a small portion of patients with head and neck squamous cell carcinoma for immunotherapy, more biomarkers are in an urgent need for the majority. Methods: Ninety-nine recurrent/metastatic patients were analyzed. PD-1 cohort including 78 patients; Non-PD-1(NPD-1) cohort including 28 patients received anti-EGFR antibody and harbored at least one of EGFR amplification/mutation, CCND1 amplification, FGF3/4/19 amplification, or CDKN2A/B mutations (including 7 patients received with both treatment). Patients were evaluated as no clinical benefit (NCB) if experiencing progressive disease or stable disease lasting < 6 months and were discontinued from immunotherapy within 3 months; otherwise, patients were evaluated as clinical benefit (CB). Tumor genomic DNA was isolated from formalin-fixed paraffin-embedded tissue for the targeted sequencing by a 769-gene panel. R package was used for fisher test to evaluate the variants. p < 0.05 was set as significant. Results: With median age of 57 years old, this study included 75 (75.8%) oral squamous cell carcinoma patients,17 (17.2%) oropharyngeal carcinoma patients and 7 others. Sixty-nine (69.7%) patients have PD-L1 CPS≥1, 27 (27.3%) patients have CPS＜1 and 3 (3.0%) have an unknown CPS. The estimated 10-month progression-free survival of the NPD-1 cohort and PD-1cohort were 60.0%and 47.6% (p = 0.06) respectively. In NPD-1 cohort, 23 patients were evaluated as CB (78.3%), and in PD-1 cohort, 41 were evaluated as CB (52.6%) (p = 0.00682), indicating EGFR amplification/mutation, CCND1 amplification, FGF3/4/19 amplification, or CDKN2A/B mutations may be negatively correlated with immunotherapies. There were 14 patients who harbored either EGFR amplification or SNV mutation. Of the 8 patients who received NPD-1 treatment, 7 were CB (87.5%); Of the 8 patients who received PD-1 treatment, 2 were CB (25%) Statistically, the difference between NPD-1 treatment group and PD-1 treatment group was significant with a p value of 0.04056. There were 16 patients who harbored CCND1 amplification, or FGF3/4/19 amplification. Of the 12 patients who received NPD-1 treatment, 10 were evaluated as CB (83.3%); Of the 7 patients who received PD-1 treatment, 1 was evaluated as CB (14.3%). The difference was significant with a p value of 0.00627. There were 44 patients who obtained CDKN2A/B mutations. Of the 12 patients who received NPD-1 treatment, 11 acquired CB (81.7%); Of the 33 patients who received PD-1 treatment, 18 acquired CB (54.5%). The difference was significant with a p value of 0.03325. Conclusions: We for the first time showed that genetic-altered EGFR, FGF3/4/19, CCND1 and CDKN2A/B were negatively correlated with anti-PD-1 therapy in clinical cohorts retrospectively and these genetic aberrations may serve as novel immune-negative biomarkers for immunotherapies.