PHOTODYNAMIC THERAPY WITH SYSTEMIC ADMINISTRATION OF PHOTOSENSITIZERSIN DERMATOLOGY

We have reviewed the results of clinical investigations into the use o f photodynamic therapy (PDT) with intravenous injection of hematoporph yrin derivative (HpD), Photofrin (PF) and Sn-protoporphyrin (Sn-Pp) or oral administration of delta-aminolevulinic acid in the treatment of skin cancers and/or psoriasis. Bowen's disease was highly responsive, provided that adequate light and HpD or PF doses were delivered. In co ntrast, poor results were shown for squamous cell carcinoma, and the r ates of complete response of basal cell carcinoma ranged between 0% an d 100%. Treatment failures could be related to the delivery of low dru g and/or light doses, but differences in the thickness and pigmentatio n of the treated lesions may play a relevant role. Good palliation was almost always achieved in patients affected by primary and secondary breast carcinomas, although complete eradication of tumors was very ra re. PDT is a very promising treatment modality for both Mediterranean and HIV-related Kaposi's sarcoma, because it appears to be effective, can be repeated and is not associated with immunosuppressive activity or significant systemic toxicity. PDT of psoriasis with low doses of S n-Pp, HpD or PF plus UVA light and PF plus 630 nm light proved to be e ffective and was associated with mild, dose-related and reversible pho tosensitivity.