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Abstract
Some of the treatment options available for non-melanoma malignant tumors of the skin are cryotherapy, topical 5-fluorouracil, curettage, electrosurgery or laser surgery, and excision. Most of the treatments are hampered by considerable discomfort during the treatment sessions and in many cases lead to scars or less than optimal cosmetic end results. Photodynamic therapy using topical photosensitizers such as ALA, is a promising new alternative that might improve the cosmetic outcome because it is less destructive than other treatment options.
Photodynamic therapy is a specialized form of photochemotherapy that depends on the presence and interaction of a photosensitizer, light and oxygen. In a typical PDT procedure the photosensitizing drug is administered either systemically or topically depending upon the location of the lesion. Over a period of time, which varies between a few minutes and a few days depending upon the photosensitizer being used, the drug becomes concentrated in the lesion compared with the surrounding normal tissue. At this point, light of a predetermined dose is directed into the lesion either using a laser or a non-laser light source. Rapid destruction of the lesion follows and the patient is typically clear of the lesion, with any normal tissue damage healed, 2–3 months later.
The aim of this study was to evaluate the efficacy, safety and cosmetics outcome of topical photodynamic therapy using laser light and non-coherent light sources in precancerous lesions and some skin tumors as actinic keratosis, Bowen’s disease and basal cell carcinoma .