In this first clinical study performed according to GCP- (good clinical practice) guidelines, efficacy, and tolerability of topical photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA) were tested in the treatment of actinic keratoses. Ten patients (6 f, 4 m) with 36 lesions (19 located on hands and arms, 17 on the head) received ALA-PDT once. Five to six hours after occlusive application of ALA (water-in-oil-emulsion containing 10% ALA) irradiation was performed with an incoherent light source. Up to 3 months after treatment patients were monitored. A score evaluating infiltration and keratosis of treated actinic keratoses allowed us to estimate therapeutic efficacy. Compared to the initial score (100%) significantly lower score-sums were observed at the 28 day follow-up at both localizations (head: 15%; hand: 67%). Complete remission (score sum 0) resulted in 71% of actinic keratoses localized on the head. Except for slight pain and burning sensations during and after irradiation there were no notable side effects. This study proved good efficacy and tolerability of topical PDT in the treatment of actinic keratoses. Whether PDT is able to compete with established treatment modalities remains to be shown in further studies.
[1]
M Landthaler,et al.
A possible new incoherent lamp for photodynamic treatment of superficial skin lesions.
,
1994,
Acta dermato-venereologica.
[2]
H Kerl,et al.
Topical photodynamic therapy with endogenous porphyrins after application of 5-aminolevulinic acid. An alternative treatment modality for solar keratoses, superficial squamous cell carcinomas, and basal cell carcinomas?
,
1993,
Journal of the American Academy of Dermatology.
[3]
J C Kennedy,et al.
Endogenous protoporphyrin IX, a clinically useful photosensitizer for photodynamic therapy.
,
1992,
Journal of photochemistry and photobiology. B, Biology.