Photodynamic therapy for the treatment of nonmelanomatous cutaneous malignancies

Photodynamic therapy (PDT) is a modality whose concept is not new to dermatologists. PDT has gained regulatory approval in the United States for the treatment of esophageal and lung malignancies. The field has grown over the last decade, and now phase II/III clinical trials using second generation drugs for the treatment of nonmelanoma skin cancers, palliation of metastases to the skin, and Kaposi's sarcomas have been introduced. These new sensitizers tend to reduce the one side effect of PDT, namely persistent generalized cutaneous photosensitivity. PDT has shown efficacy in (1) patients who have failed conventional therapies, and for whom local treatment options are limited (2) patients in whom surgery would result in cosmetic disfigurement, and (3) patients prone to developing multiple lesions as in Gorlins syndrome. Dosimetry is based on well-understood treatment matrices that have optimized light delivery with known photosensitizer administrations. The advantages of PDT for cutaneous malignancies include the ability to treat numerous lesions in one setting, in a noninvasive manner without any apparent concern for the development of carcinogenicity.