Photodynamic therapy
Photodynamic therapy (PDT) is based on the use of the light-sensitive (photosensitive) agent, 5- aminolevulinic acid (5-ALA). This is applied topically to the skin cancer or precancer or injected into the bloodstream. It is absorbed preferentially by the tumor cells. When exposed to a powerful light source, usually the laser, the following day, the chemical is activated to destroy the cancer.
It is currently used most often for numerous superficial BCCs, and has Food and Drug Administration approval as a treatment for actinic keratoses.
