Treatment of superficial basal cell carcinomas using topically applied delta-aminolaevulinic acid and a filtered xenon lamp.

Objective: To evaluate the treatment of superficial basal cell carcinomas (SBCC) using photodynamic therapy with topically applied delta-aminolaevulinic acid (ALA) and a filtered short arc xenon lamp as a light source.

Method: An oil-in-water emulsion containing 20% ALA was applied topically to the lesion sites which were then occluded for 3 h. Irradiation was performed in a single session of 10 min using 125 or 166 mW/cm2 in the wavelength range (620-670 nm, giving a radiation dose of 75 or 100 J/cm2, respectively. Urine samples obtained in connection with the treatment were examined for traces of porphobilinogen and porphyrin. The therapy outcome was determined by histological examination of punch biopsies or by clinical verification. A follow-up scheduled for 5 years was initiated.

Patients: A group of 37 patients with histologically verified SBCCs were included. A total of 190 SBCCs were treated. Also included were six patients with 10 nodular basal cell carcinomas and five patients with 18 Mb. Bowen. The urine samples from three patients showed traces of porphyrins.

Results: Of the 157 SBCCs followed-up for 6 months, 144 were cleared giving a clearance rate of 92%. Of the nodular basal cell carcinomas and Mb. Bowens, 2 of ten and 11 of 18 were cleared, respectively.

Conclusion: Photodynamic therapy is well suited to the treatment of SBCCs giving good cosmetic results regardless of lesion size. The filtered xenon lamp proved to be particularly suitable for photodynamic therapy.