Abstract
BACKGROUND: Anti-PD1 inhibitors have been approved for the treatment of recurrent or metastatic head and neck cancer (HNC), as a result of Global Phase III trials. However, the clinical outcomes of immune checkpoint inhibitors in patients who are not eligible for clinical trials or have various medical conditions have not been fully elucidated. METHODS: We retrospectively reviewed 46 patients with recurrent or metastatic HNC who received pembrolizumab or nivolumab between June 2016 and June 2019. RESULTS: Thirty-five patients had head and neck squamous cell carcinoma (HNSCC) affecting the oropharynx, oral cavity, hypopharynx, larynx, nasal cavity, or paranasal sinuses, and eleven patients had nasopharyngeal cancer (NPC). The median progression-free survival (PFS) and overall survival (OS) were 3.7 months and 6.8 months, respectively, for patients with HNSCC, and 4.3 months and 11.8 months, respectively, for patients with NPC. The objective response rate (ORR) in all patients was 21%. Of 30 patients with HNSCC, 5 patients achieved complete response and 2 achieved partial response (ORR 23%); 1 of 8 NPC patients achieved partial response (13%). Patients who previously underwent radiotherapy had better OS than those who did not (median OS, 7.6 months vs. 2.3 months, p = 0.006). OS was longer in patients treated with pembrolizumab than in those treated with nivolumab (median OS, 11.8 months vs. 6.8 months, p = 0.017). CONCLUSION: Consistent with previous reports, immune checkpoint inhibitors showed promising efficacy in patients with previously treated recurrent or metastatic HNC in a real-world setting.