Real-World Treatment Trajectories Following Near-Infrared Photoimmunotherapy in Head and Neck Cancer: Implications for Clinical Decision-Making.

PURPOSE: Near-infrared photoimmunotherapy (PIT) is a relatively new locoregional treatment for head and neck cancer. However, real-world data on its use in clinical practice, particularly regarding treatment trajectories, remain limited. This study described the clinical patterns following PIT in a real-world setting. METHODS: This retrospective single-center case series included 12 patients with head and neck cancer treated with PIT. Patients were grouped into four patterns based on their clinical courses: planned repeated PIT, sequential systemic therapy, early discontinuation, and local control with functional compromise. Clinical characteristics and outcomes were analyzed descriptively. RESULTS: Clinical courses after PIT were heterogeneous, and four distinct patterns were observed. Five patients (42%) underwent planned repeated PIT, typically for bulky or extensive mucosal disease. Four patients (33%) transitioned to systemic therapy, mainly immune checkpoint inhibitors, due to residual or metastatic disease. Two patients (17%) discontinued treatment early because of rapid progression or complications. One patient (8%) achieved local tumor control but developed significant functional impairment due to fistula formation. No treatment-related mortality was observed. CONCLUSIONS: PIT may be a versatile treatment option in head and neck cancer. Treatment trajectories after PIT varied substantially and may thus provide clinically relevant information for subsequent decision-making. PIT may be best implemented as a flexible component within an individualized multimodal treatment strategy. These findings provide preliminary real-world evidence to inform patient selection and treatment sequencing following PIT.