Swiss Researchers Shrink Mesothelioma Tumors with Combination Photodynamic Therapy/Immunotherapy

Photodynamic therapy and immunotherapy are two innovative treatment approaches that have delivered positive results in mesothelioma clinical trials. Based on these findings, Swiss researchers pursued a novel approach that combined the use of those two protocols, and have reported dramatic, positive results.

Novel Approach Results in Dramatic Shrinkage of Mesothelioma Tumors

The mesothelioma researchers hail from the Division of Thoracic Surgery of the Centre Hospitalier Universitaire Vaudois in Lausanne, Switzerland. Writing in the European Journal of Cardiothoracic Surgery, they describe a process in which mesothelioma cells were first targeted with a chemical that made them more sensitive to light, then exposed to low-dose photodynamic therapy which boosted their expression of a molecule that attracts immune system cells, thus allowing the immune system to attack the mesothelioma tumors and stop them from growing.

The treatment resulted in approximately one out of every three of the mesothelioma-infected mice experiencing complete regression of their tumors. Though there could be a significant difference between clinical laboratory results and human results, the researchers hope that their findings will lead to the combined therapy being offered to patients and yielding similar benefits.

How Photodynamic Therapy Affects Mesothelioma Cells

While immunotherapy and its positive impact on cancers like mesothelioma has been very much in the news, photodynamic therapy is less familiar to the public. Researchers have found that it can stop blood vessels that feed nutrients into mesothelioma tumors from forming. This is one of the first studies to combine the two approaches, and the scientists are pleased with the responses that the combination evoked. 

“The combination of L-PDT with anti-CTLA4 caused complete MPM regression in 37.5% of animals,” they wrote, concluding, “The combination of L-PDT with immune checkpoint inhibitor anti-CTLA4 allows best tumor control and regression.”

If you or someone you love has been diagnosed with malignant mesothelioma, it’s essential that you have the most up-to-date information. For more resources, contact the Patient Advocates at Mesothelioma.net at 1-800-692-8608.

Written by Terri Oppenheimer

Terri Heimann Oppenheimer is the head writer of our Mesothelioma.net news blog. She graduated from the College of William and Mary with a degree in English. Terri believes that knowledge is power and she is committed to sharing news about the impact of mesothelioma, the latest research and medical breakthroughs, and victims’ stories.

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