Background/aim: In December 2019, pembrolizumab was approved in Japan for the treatment of head and neck cancer with recurrence or distant metastasis, making it a new option for first-line treatment. However, there are still many unanswered questions about Overall survival (OS), Progression free survival (PFS), adverse events including immune-related adverse events (irAEs), and biomarkers.
Aims/objectives: The aim of this study was to retrospectively review first-line treatment of head and neck cancer with recurrence or distant metastasis treated with pembrolizumab and to determine whether Combined positive score (CPS) is still useful as a biomarker in the clinical practice.
Material and methods: We retrospectively reviewed clinical records of 20 patients who received pembrolizumab as first-line treatment for head and neck cancer with recurrence or distant metastasis between December 2019 and March 2021.
Results: Age ranged from 45 to 83 years (median 66 years), 17 male patients and 3 female patients. The response rate was 40%, and the disease control rate was 60%. OS and PFS in patients with CPS < 1 were significantly worse than those with CPS ≤ 1 (CPS-positive patients). The OS and PFS of patients with CPS < 1 were s ignificantly worse than those of p atients with 1 < = CPS (CPS-positive p atients), and there was no significant difference between the group with CPS between 1 and 20 and the group with CPS over 20. And we experiences several CR cases with high CPS.
Conclusion: CPS is a useful biomarker for pembrolizumab.
Significance: There are no reported cases of CR after two courses of pembrolizumab in head and neck cancer. There are no reports of pembrolizumab in patients with head and neck cancer in Japan.