Temoporfin-mediated photodynamic therapy in advanced, incurable head and neck squamous cell carcinoma: A prospective multicenter study

Abstract

17001 Background: To confirm the earlier reported efficacy of temoporfin-mediated photodynamic therapy (PDT) in patients with advanced, end-stage head and neck squamous cell carcinoma (HNSCC). Methods: In a prospective multicenter study, thirty-nine patients with HNSCC lesions ≤ 10 mm in depth, recurring following standard multimodality treatment, were intravenously injected with temoporfin, followed 96 hours later by illumination of the tumor surface with 652 nm laser light. Tumor response (World Health Organization criteria), quality of life (European Organization for Research and Treatment of Cancer -EORTC - Quality of Life Questionnaire QLQ-C30 and QLQ-H&N35) were assessed on an intention-to-treat basis. Treatment related toxicity (Common Toxicity Criteria - CTC) was documented rigorously. Results: 54% [95% CI: 37%; 70%] of 39 patients showed an objective tumor response (OR) and 49% [95% CI: 32%; 65%] achieved a complete response (CR; intention-to-treat analysis). Looking only at 31 evaluable patients OR was 67.7% and CR was 61.3%. At 40 weeks, a 90.5% [95% CI: 69.6%; 98.8%] survival was observed in responders as opposed to 38.9% [95% CI: 17.3%; 64.3%] for non- responders. At that point in time, between 50 and 100% of patients reported improvement in most domains of the EORTC QLQ-C30 and EORTC QLQ-H&N35. Observed treatment emergent adverse events (TEAE) were mostly cancer pain in 21% of patients, pain in general and dysphagia in 13% and phototoxicity reactions in 41%; these TEAE were mostly CTC grade 1 and 2. Conclusions: Patients with advanced HNSCC ≤ 10 mm in depth, who have exhausted other treatment options, can achieve significant local control, survival and quality of life benefit from temoporfin-mediated PDT. As opposed to conventional treatment modalities, this treatment is tolerated well. Acknowledgements: We thank the TEM-HNC-001 study group for their help and support. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Expert Testimony Other Remuneration Biolitec Pharma Biolitec Pharma Biolitec Pharma Biolitec Pharma Biolitec Pharma