Photodynamic therapy (PDT) uses light-activated drugs and a laser to destroy cancer cells and treat symptomatic tissues.
During PDT, a patient is injected with a photosensitizing drug to make cells more sensitive to light. The drug is absorbed by the cancer cells, and the treatment area is exposed to a spectrum of light which activates the drug to destroy the cancer cells. PDT kills cancerous cells while sparing much of the nearby healthy tissue.
PDT takes minutes to complete. It can be performed on an outpatient basis, is relatively pain-free, requires minimal sedation, involves less risk than surgery and has minimal side effects because healthy tissue is spared. Unlike radiation therapy and chemotherapy, PDT can be repeated on the same area, which makes it a good option for treating tumors that recur. The most common side effect is sensitivity to bright light, which lasts four to six weeks.