Head and neck squamous cell carcinoma (HNSCC) is the most common cancer arising in the head and neck region. The most common risk factors are smoking, excessive drinking, and human papillomavirus (HPV) infection. While the overall incidence of smoking is decreasing, the incidence of HPV-related HNSCC is increasing in the United States and Western Europe, which led to a shift in understanding of the pathophysiology, treatment, and prognosis of this disease. The outcomes for non-metastatic HNSCC remains very encouraging and continues to improve. Advances in radiation technology and techniques, better organ preserving surgical options, and multidisciplinary treatment modalities have improved cure rates for locally advanced HNSCC patients. The treatment of metastatic disease, however, remains an area of need. The advancement of immune checkpoint inhibitors has provided significantly better outcomes, but only a small proportion of patients obtain benefits. Most recurrent and/or metastatic HNSCC patients continue to have poor survival. This has led to the vigorous investigation of new biomarkers and biomarker-based therapies. Novel therapeutic options including adaptive cellular therapy and therapeutic vaccines are also on the horizon. In this review, we highlight the latest advances in the field of HNSCC and the future direction of research.

We hypothesized the combination of cetuximab and nivolumab would improve survival in recurrent and/or metastatic (R/M) HNSCC by providing synergy in cancer control and evaluated toxicities and efficacy of the combination. Effects of sequential administration of cetuximab and anti-Programmed Cell Death-1 checkpoint inhibitors (CPI) were also explored. Patients who failed at least one line of palliative treatment for incurable HNSCC were treated with cetuximab 500 mg/m² IV on Day (D)-14 as a lead-in followed by cetuximab 500 mg/m² IV and nivolumab 240 mg/m² IV on D1 and D15 every 28-D cycle. Electronic health record-derived real-world data (RWD) were used to explore sequential treatment effects of CPI and cetuximab. A total of 45 evaluable patients were analyzed, and 31/45 (69%) patients had prior exposure to either CPI or cetuximab. The only grade 4 treatment-related adverse event was cetuximab infusion reaction in one patient. The 1-year progression-free survival (PFS) and overall survival (OS) rates were 19% and 44%, respectively. Although patients with no prior CPI (23/45, 51%) showed a trend for more favorable PFS relative to patients with prior CPI (22/45, 49%), the improvement in the 1-year OS did not reach the statistical threshold. For evaluation of sequential CPI and cetuximab treatment effects, we selected RWD-cetuximab cohort with 173 patients and RWD-CPI cohort with 658 patients from 6862 R/M HNSCC. Our result suggested patients treated with RWD-cetuximab after RWD-CPI had worse OS compared to no prior RWD-CPI (HR 1.81, 95% CI 1.02–3.16). Our data suggest the combination of cetuximab and nivolumab is well tolerated. Optimal sequencing of cetuximab and CPI may have an impact in prognosis and requires further evaluation.