Earlier this year, the American Society of Clinical Oncology, or ASCO, issued its latest guidelines for the treatment of malignant pleural mesothelioma. The first update since 2018, the new guidance represents a significant shift that reflects advancements from 110 studies conducted between 2016-2024. The new guidelines represent a sea change in how surgery and immunotherapy are used, as well as increases in genetic testing.
New Guidelines Reduce Surgery’s Role in Mesothelioma Treatment
Though previously a mainstay of pleural mesothelioma treatment, ASCO’s new guidelines suggest a more limited role in pleural mesothelioma treatment. Surgical removal of tumors is now only recommended for patients with limited disease and epithelioid subtype and should only be performed at high-level mesothelioma centers with extensive experience in treating the disease.
This change stems largely from the phase 3 MARS-2 trial, which found that mesothelioma patients who received chemotherapy alone had longer median overall survival (24.8 months) compared to those with surgery plus adjuvant chemotherapy (19.3 months). Quality of life measures and cost also favored chemotherapy. However, Expert Panel Co-chair Hedy Kindler, MD, of The University of Chicago Medicine notes that the group isn’t “closing the door on surgery” entirely, as high-volume centers have shown better outcomes than those in MARS-2 for carefully selected patients.
Immunotherapy and Genetic Testing Play Increased Role Under New Mesothelioma Guidelines
The guidelines highlight two new immunotherapy approaches to mesothelioma treatment. First-line ipilimumab/nivolumab, approved in 2020, is now recommended, especially for non-epithelioid pleural mesothelioma patients after the CheckMate-743 trial results showed significant survival benefits for non-epithelioid patients (18.1 vs. 8.8 months median OS). For epithelioid PM, treatment options include immunotherapy, chemotherapy, or a recently approved chemoimmunotherapy regimen that combines pembrolizumab with pemetrexed/platinum. The group stresses that treatment should be based on each patient’s individual comorbidities, toxicity tolerance, and treatment goals.
The guidelines also now recommend offering germline testing to all pleural mesothelioma patients, as identifying genetic mutations makes a difference in treatment decisions and patient prognosis. Dr. Kindler and her co-chair, Dr. Raffit Hassan of the National Cancer Institute’s Center for Cancer Research, noted the significance of recent scientific advances in treating the rare asbestos-related disease. Dr. Kindler called the progress “incredibly exciting,” while also saying that “clearly much more needs to be done.” She expressed optimism about several new drugs for mesothelioma that are under development.
If you or someone you love has been diagnosed with malignant mesothelioma, breakthroughs in treatment offer real hope. For more information and resources, contact the Patient Advocates at Mesothelioma.net today at 1-800-692-8608.
