Photodynamic therapy for cutaneous and subcutaneous malignant neoplasms

Twenty-seven patients with cutaneous and subcutaneous malignant neoplasms were treated with photodynamic therapy. Therapy was administered to 248 areas during a total of 72 separate treatment sessions after patients received a total of 45 injections of sensitizer. Seven patients had basal cell carcinoma, three had squamous cell carcinoma, three had malignant melanoma, one had liposarcoma, and 12 had breast cancers. One patient had Bowen's disease. Treatment was given either by surface radiation or interstitially. One month after treatment, 48 (67%) of the treatment sessions resulted in a complete response (no clinical evidence of tumor), and 19 (26%) resulted in a partial response (greater than 50% reduction in the number or size of tumors). Fifteen patients were examinable 12 months after treatment, and in this group, 31 treatment sessions were evaluated as a complete response one month after therapy, 15 (48%) of which retained this status at one year after treatment. By comparing the ability of different light-delivery instrumentation, it was concluded that the Yellow Springs radiometer (Yellow Springs Instruments, model 65A, Yellow Springs, Ohio) provided the most reliable spot power density readings. Straight-tipped fibers are nonhomogeneous and can result in overtreatment of the central area with necrosis and pain and in undertreatment of the periphery.