Photodynamic therapy as salvage therapy for patients with nasopharyngeal carcinoma experiencing local failures following definitive radiotherapy

Background: Treating local failures of nasopharyngeal carcinoma (NPC) is a challenge. This study evaluates photodynamic therapy (PDT) in the treatment of residual and recurrent NPC. Method: In this phase II study, patients with local recurrent or residual NPC after curative intent (chemo-) radiation could be included. Exclusion criterion was a tumour depth more than 10mm. Foscan® 0.15mg/kg was administered intravenously. After 96h, the illumination was performed under local anaesthesia with a nasopharyngeal light applicator. Tumour response was measured 10 weeks after illumination by endoscopy, biopsy and CT-scan. Kaplan-Meier method was used for survival analysis. Results: Twenty-one patients were included. Fourteen patients were treated for residual disease (67%), and two for recurrent (10%). For five patients this distinction could not be made, due to uncertainty about complete response after initial treatment. The median follow-up time was 32 months. Twenty patients (95%) had a complete response 10 weeks post-treatment. Two patients had recurrent local disease at 5 and 7 months post-PDT. They received another course of PDT, one with success. The 2-year local control rate was 75%, progression free survival was 49% and overall survival was 65%. Nine patients (43%) had no evidence of disease and were in a good clinical condition (ECOG Performance Scale 0) at the end of the study period. No serious adverse events were observed. Conclusion: This study showed that PDT is effective in treating local failures of NPC with a depth of less than 10. mm. The treatment was easy to perform under local anaesthesia. Especially in regions were other modalities like radiation and surgery are limited PDT can be a good alternative treatment.