Basal cell carcinoma (BCC) of the skin is the most common type of cancer that can be treated with various therapies including surgical removal. A number of factors can lead to the development of multiple BCC of the skin, including genetic disorders (e.g., nevoid basal cell carcinoma syndrome). Treatment of multiple BCC becomes much more challenging. In these trials, the experimental therapy: verteporfin PDT is compared to placebo PDT. PDT or photodynamic therapy in these studies is the combination of the photoactive drug verteporfin (given intravenously) and red light exposure of skin tumors.

The primary objective is to assess whether verteporfin PDT can completely eliminate multiple BCCs. Eligible subjects will have at least 3 BCCs. Study subjects won't know which treatment they have been been assigned to - this is done randomly (like flipping a coin). After study treatment, the BCCs in each subject will be closely observed and toward the end of the study all will be surgically removed and examined to verify response to study treatment. Safety will be assessed by testing blood samples before and after study treatment, and analyzing adverse events and skin reactions to the study treatment.