A recent review study discussed a novel treatment known as photodynamic therapy, often used to reduce tumors prior to surgery. The method represents a potentially promising strategy for the treatment of mesothelioma, the authors said in the article, “Photodynamic Therapy in Non-Gastrointestinal Thoracic Malignancies,“ published in the International Journal of Molecular Sciences.
Photodynamic therapy involves initial treatment with what is called a photosensitizing agent, a compound that is sensitive to light. The photosensitizing agent is injected into the bloodstream and selectively accumulates in tumors. A clinician can then apply light to specific regions of the body where the tumors are known to exist. The light wavelengths are specific to activate the photosensitizing agent.
The treatment has mostly been used for people with cancer of the thorax, the region between the neck and abdomen. Porfimer sodium is the most common FDA-approved photosensitizing agent.
In addition to killing tumor cells in cancers, photodynamic therapy also has the advantage of cutting off the blood vessels that feed tumors and allow them to grow.
Researchers have conducted several clinical trials using photodynamic therapy for pleural mesothelioma. Overall, they concluded that the treatment can be effective when used in combination with other cancer therapies. Some caution is necessary, however, and the treatment may not be for everyone since esophageal fistulas can develop with photodynamic therapy.
The authors concluded, “Photodynamic therapy has also shown promising results in mesothelioma and pleural-based metastatic disease. As new generation photosensitizers are being developed and tested and methodological issues continue to be addressed, the role of photodynamic therapy in thoracic malignancies continues to evolve.”
Mesothelioma refers to malignant tumor of lining organs such as the lungs, stomach and heart. Pleural mesothelioma, an aggressive cancer, is the most common form of the disease, amounting to 75 percent of all mesotheliomas. Its main cause is asbestos exposure, its one-year survival rate is only 38 percent. Based on this low rate of survival, additional treatments are greatly needed.