Definition of photodynamic therapy
Photodynamic therapy is a cancer treatment that uses medications to make cancer cells and other abnormal cells vulnerable to special lights, such as lasers.
Photodynamic therapy involves applying a drug that makes the cells light sensitive. For cancers on or near the surface of the skin, the drug may be applied topically. For other cancers, the drug may be injected into a vein.
After a day or two, your doctor exposes the cancer cells to a certain wavelength of light. For cancers inside the body, this may require passing the light down a thin, flexible tube and into your esophagus or your windpipe (trachea) to reach the area.
The light kills the cells that have absorbed the light-sensitive medication.
Photodynamic therapy may be useful in treating conditions such as:
- Esophageal cancer
- Barrett’s esophagus
- Bile duct cancer
- Bladder cancer
- Certain skin diseases, including precancerous skin changes (actinic keratosis) and nonmelanoma skin cancer
- Lung cancer
- Stomach cancer
- Throat cancer