5-Aminolevulinic acid photodynamic therapy for superficial basal cell carcinoma

Treatment of superficial basal cell carcinoma with topical 5-aminolevulinic acid photodynamic therapy (ALA-PDT) offers an alternative to plastic surgery and radiotherapy with potential for good cosmetic outcome and local control of disease. We report our clinical experience with this technique. Patients were treated prospectively on a study protocol enrolling a total of 118 patients (63 male, 55 female) with an average age of 65 years. Consecutive patients meeting eligibility criteria were invited to participate over a four year period. Median followup was 27 months (range 1 to 76 months). In the study group, 62 patients had single lesions and 56 had multiple lesions. Of the 56 patients with multiple lesions, 33 had 2-4 lesions, 11 had 5-9, and 11 had 10 or more. All patients were treated with 20% ALA dissolved in Glaxal Base applied to the tumors for three to four hours. Following removal of the cream, fluorescence intensity and distribution were assessed using a UV-A lamp, and the lesions were exposed to photoactivating light of wavelength greater than 600 nm for a light dose ranging from 100-150 J/cm2. Lesions were reassessed in followup, and scored as complete or partial responses. At subsequent patient assessments, lesions were scored as continued complete responses or recurrences. In the patients with single lesions, there was an initial complete response rate of 90.3%. Of the 56 patients with multiple lesions, 44 had all of their lesions respond completely, and there was an overall average response rate of 95.5%. Sixty three percent of males and 44% of females had all of their lesions respond completely. (p=0.033, Chi-squared test). There was no difference in response rate with respect to age, or site of lesion. The recurrence rates were 35% for patients with single lesions, and 10.5% for patients with multiple lesions. ALA-PDT would appear to be a promising alternative to conventional treatment for superficial basal cell carcinoma. Based on these results, we are currently studying treatment with prolonged ALA exposure time (18 hours) and an improved light delivery system, and are collecting data on cosmetic outcome