TITLE:
Efficacy of Immune Checkpoint Inhibitors after Photoimmunotherapy for Head and Neck Cancer
AUTHORS:
Yukiomi Kushihashi, Isaku Okamoto, On Hasegawa, Kunihiko Tokashiki, Kiyoaki Tsukahara, Tatsuo Masubuchi
KEYWORDS:
Unresectable Locally Advanced or Recurrent Head and Neck Cancer, Photoimmunotherapy, Immune Checkpoint Inhibitor, Pembrolizumab, Nivolumab
JOURNAL NAME:
International Journal of Otolaryngology and Head & Neck Surgery,
Vol.15 No.1,
January
21,
2026
ABSTRACT: We conducted a multicenter study in collaboration with the Head and Neck Oncology Center of International University of Health and Welfare Mita Hospital and the Departments of Otolaryngology-Head and Neck Surgery and Oral and Maxillofacial Surgery/Orthodontics at Tokyo Medical University Hospital, and accumulated 40 cases (80 cycles) of head and neck photoimmunotherapy (PIT). Among these, we focused on 21 patients who received initiation or re-administration of immune checkpoint inhibitors (ICI) after PIT and performed a detailed analysis. The endpoints were overall response rate (ORR), disease control rate (DCR), complete response (CR) rate, overall survival (OS), progression-free survival (PFS) after ICI initiation, and progression-free survival 2 (PFS2), defined as the interval from the first PIT session to subsequent disease progression. The observed ORR, DCR, and CR rate after ICI initiation were 43.0%, 62.0%, and 19.0%, respectively. The median OS (mOS), median PFS (mPFS), and median PFS2 (mPFS2) were 14.3, 12.1, and 19.7 months, respectively. The median observation periods for OS, PFS, and PFS2 were 10.9, 4.3, and 10.8 months, respectively. In this study, favorable outcomes were obtained, suggesting that the introduction of ICI after PIT may represent an effective therapeutic strategy for unresectable locally advanced or recurrent head and neck cancer.