According to Baylor College of Medicine research published in Clinical Cancer Research and reported by Science Daily, patients with resectable malignant pleural mesothelioma (tumors that can be surgically removed) who received immunotherapy before surgery had better clinical outcomes. This research establishes the groundwork for the future use of neoadjuvant immunotherapy in mesothelioma treatment.
Dr. Bryan Burt, the paper’s primary author, professor, and chairman of the David J. Sugarbaker Division of Thoracic Surgery at Baylor’s Michael E. DeBakey Department of Surgery described mesothelioma as “a horrible disease with little survivorship.” This disease has “always defied all conventional treatment.”
Immune checkpoint inhibitors are a kind of cancer immunotherapy medication. Despite its groundbreaking significance in cancer treatment, its use in mesothelioma was not recognized until recently. After recent success in treating patients with unresectable mesothelioma, Burt and colleagues investigated immunotherapy for its potential in treating resectable mesothelioma.
“Surgery may not be curative,” said Burt, who works at Baylor’s Dan L. Duncan Comprehensive Cancer Center. “However, combining surgery with another therapy frequently results in improvement.” This study is an essential first step in determining whether or not checkpoint inhibitor medication before surgery is safe and practical.
Immunotherapy can trigger an immune response long after the tumor has been surgically removed. The immune system has prepared for a probable tumor return. Participants in this study were randomly assigned to one of two groups according to whether their mesothelioma was judged resectable.
The first patient received one therapy cycle of durvalumab, which inhibits the PD-L1 checkpoint. The second group received a single treatment cycle of durvalumab, a CTLA-4 checkpoint inhibitor, plus tremelimumab, another immunotherapy medicine. Immunotherapy was given to both groups around three weeks before surgery.
Surgeons collected samples before treatment, administered immunotherapy, and then excised additional tissue during the resection process to evaluate the medications’ effects on the tumor microenvironment and immune cells within the tumor.
The researchers discovered that combining immunotherapy with durvalumab and tremelimumab had a profound and favorable effect on the tumor microenvironment. The dual drug immunotherapy boosted the number of CD8 T cells within the tumor, the “soldiers” of the immune response that can destroy or remember the tumor. Even though this was not the project’s primary aim, overall survival was much higher in the dual medication immunotherapy group.
Researchers are still tracking study participants who got the intervention more than three years ago. Burt and Baylor’s mesothelioma surgeon, Dr. R. Taylor Ripley, hope to undertake a more extensive study comparing the efficacy of dual-agent immunotherapy to that of chemo-immunotherapy.
