Hematoporphyrin derivative photoradiation therapy in managing nevoid basal-cell carcinoma syndrome. A preliminary report.

Hematoporphyrin derivative (HpD) is a photodynamically active dye that is preferentially retained by malignant tissues and initiates a cytotoxic reaction when exposed to red light. Normal tissues adjacent to a tumor retain HpD to a lesser degree and are thus spared damage from the light-induced reaction. We describe the treatment of 40 basal-cell carcinomas in three patients with nevoid basal-cell carcinoma syndrome. All treated lesions showed disappearance of clinically apparent tumor within four to six weeks, and there was no damage to surrounding skin. Thirty-three lesions (82.5%) showed complete response on biopsy findings, while seven showed residual tumor cells. The recurrence rate was 10.8%, with the follow-up ranging from 12 to 14 months. Tumor response was related to the total light dose delivered and the size and location of the tumor.