Recently published in Seminars in Thoracic and Cardiovascular Surgery, an article on photodynamic therapy highlights the effectiveness of the treatment in mesothelioma cancer.
Caused almost exclusively by asbestos exposure, malignant mesothelioma is an aggressive cancer that usually affects the lining of the lungs but can also affect the lining of the abdomen or heart. Unfortunately, mesothelioma has earned a reputation as a cancer that is difficult to treat. It rarely responds to aggressive treatment approaches and no cure has been found, but combining therapies has shown to extend the survival rate and improve prognosis in some cases.
Combining one or more therapies, known as multimodality therapy, has shown the greatest improvements in mesothelioma treatment. Uniting surgery, chemotherapy and radiation therapy is currently the most effective multimodality treatment, however not all mesothelioma patients qualify for this aggressive approach.
Therapies that reduce the amount of cancer treatment reaching nearby vital organs tend to be the easiest on mesothelioma patients. Photodynamic therapy (PDT) is one of these treatments that aim to treat the tumor while sparring exposure to neighboring organs and tissues.
PDT is a light-based treatment consisting of three components: a nontoxic photosensitizing compound, oxygen and visible light. The three components independently have no effect, but the combination is lethal to treated cells. The treatment is primarily delivered by means of intracavitary administration during the surgical procedure but can also be performed when surgery is not an option.
The FDA has approved PDT for several forms of cancer, but the treatment remains in the experimental stage for mesothelioma patients. When used on mesothelioma patients, PDT usually follows surgical removal of the tumor and endeavors to eliminate residual microscopic disease (tiny, remaining portions of the primary tumor).
Researchers report that PDT has successfully been paired with lung-sparing pleurectomy and decortication and does not prevent other treatments such as chemotherapy or radiation. They also note that “PDT appears to bolster an immunologic effect by rendering the cancer cells that have been destroyed by the light-activated photosensitizer more presentable to the immune system. Local control and survival rates have been sufficiently rewarding to merit ongoing development of this combination of surgical technique and PDT.”
Additional information about mesothelioma and treatment options may be found through the mesothelioma Center.