Photodynamic Therapy

What is Photodynamic Therapy? Photodynamic therapy, a new treatment now being used in patients with certain types of cancer, uses a combination of a photoactive drug ( a drug that is activated by light), and light from a laser. Both work to allow the doctor to specifically target and destroy cancer cells while limiting damage to surrounding health tissue.

How does Photodynamic Therapy work against cancer? First, you will be given an injection of the photoactive drug Photofrin (porfimer sodium). Photofrin will be absorbed by your body's tissues, including cancer tissue. Over the next couple of days, the drug will largely be eliminated from most healthy tissue, but will remain in cancer cells. (It also will remain for a while longer in skin).

Approximately 40 to 50 hours after the Photofrin injection, light from a laser will be directed at the cancer cells. The application of light takes approximately 5 to 40 minutes depending on the amount of tumor your doctor wants to treat. For many patients the entire procedure takes under one hour. The light will activate the drug present within those cells and destroy them.

Because Photofrin is retained to a greater degree by cancer cells than by healthy cells, most of the healthy tissue surrounding the tumor will not be affected.