Photodynamic therapy, or PDT, is used in dermatology and oncology to treat several skin conditions, including cancers, pre-cancers, acne and psoriasis. PDT is based on the use of a photosensitizing drug and a light source that activates it. Activation of the drug leads to production of oxygen molecules that will kill nearby cells. Atypical and cancerous cells take up more drug and retain it longer and, thus, PDT kills these cells instead of your normal cells.

Cancer Conditions

Basal cell carcinoma is one of the conditions that can be treated with PDT.  This is a slow-growing non-melanoma skin cancer and the most common form of cancer in the United States. PDT is also used to treat pre-cancers like actinic keratosis. Actinic keratoses are skin lesions that form after years of exposure to ultraviolet light. Actinic keratoses are considered to be an early stage of skin cancer, including melanoma. PDT can also be used to treat lung cancer, esophageal cancer and Barrett's esophagus.

Non-Cancer Conditions

PDT is used in dermatology to treat conditions like acne, rosacea, sun damage, oily skin, wrinkles, warts and psoriasis. Treatment of acne is based on the destruction of the sebaceous or oil glands which will then lessen the symptoms of acne. PDT is also used to treat macular degeneration. Macular degeneration is a condition of the eye caused by abnormal growth of blood vessels that begin to leak. PDT will seal the leaky blood vessels and slow down the resulting vision loss. PDT is not used to treat moles and birthmarks.