Systemic photodynamic therapy with Photofrin for naevoid basal cell carcinoma syndrome-A pilot study.

Background: Treatment of basal cell carcinomas in naevoid basal cell carcinoma syndrome (NBCCS) poses several challenges. The sheer numbers of such lesions in these patients makes traditional therapeutic modalities like surgery, impractical. Topical photodynamic therapy (PDT) with δ-5-amino levulinic acid has increasingly been recognised as and safe and effective choice in the treatment of BCC. The probability of local control of BCC treated by PDT depends strongly on lesion thickness, thick nodular lesions being less responsive. Response to treatment is monitored by the reduction in the lesional size, but histopathological confirmation of regression is often required.

Method: We used systemic photodynamic therapy with Porfimer Sodium (Photofrin(®), Axcan Pharma Inc., Quebec, Canada), a systemic photosensitizer for treating multiple BCC in seven patients with NBCCS. Treatment response was monitored using a high resolution 20MHz ultrasound.

Results: There was a substantial reduction in the number of superficial basal cell carcinomas with complete US regression after one treatment. A 74.2% reduction was seen in the size of thick lesions treated with external light. Thick nodular lesions in two patients treated with interstitial optical diffuser fibres in addition to external light showed 87.6% reduction in size as measured by high resolution ultrasound.

Conclusions: Our preliminary results indicate that systemic photodynamic therapy using Photofrin and external light either alone or with interstitial optical diffuser fibres; may be effective in treatment of multiple, thick and nodular BCC lesions in Naevoid basal cell carcinoma syndrome. Further studies are needed to confirm our observations. We found high resolution ultrasound an effective alternative to histopathological analysis in monitoring the response to treatment.