Photodynamic treatment of skin malignancies with aminolevulinic acid. Emphasis on anatomical observations and in vivo erythema visual assessment.

BACKGROUND: Photodynamic therapy with delta-aminolevulinic acid is a promising alternative treatment for superficial skin malignancies.
OBJECTIVE: Further clinical experience, study of tissue alterations leading to recovery, and correlation/prediction of the therapeutic response through in vivo skin color changes as represented by erythema development.
METHODS: The therapeutic procedure, sequential histology and histochemistry, and the development of a remote machine vision system to measure, map, and monitor the erythema development. RESULTS/
CONCLUSIONS: A high cure response rate with adequate follow-up was shown. A significant correlation of the clinical-histologic response of tumors subjected to treatment with the erythema measurements implies that erythema inspection and quantitative analysis offer a reliable predictor of the therapeutic outcome and a clue for optimization of this treatment modality.