First experience with Foscan® mediated photodynamic therapy for head and neck tumours

Introduction. The authors aimed to determine the efficacy and the importance of in situ light dosimetry in photodynamic therapy (PDT) with the second generation photosensitizer Foscan^® as a new treatment modality for head and neck tumours. Material and methods. From April to August 1997 11 patients with 13 tumours were treated with PDT in the Netherlands Cancer Institute. The incident light dose was 20 J/cm² (healthy mucosa shielded) at 4 days after 0.15 mg/kg Foscan^® (i.v.). Light dosimetry was performed. Results. There were eight complete responses, one recurrence, five partial responses (tumours larger than 4 cm and in a heavily pigmented tumour), after follow-up of 6–18 months. In all cases the total tissue light dose (including scattered and reflected light) was higher than the incident light dose (110–450%). Conclusion. Foscan^®-mediated PDT offers effective alternative to standard treatment modalities in head and neck cancer. In situ light dosimetry is necessary for standardisation of this treatment.