A new blood test can detect hidden mesothelioma, a rare and aggressive cancer, with greater accuracy than traditional imaging scans. This breakthrough could revolutionize treatment for patients with mesothelioma, which often goes undetected until it reaches advanced stages.
The Challenge of Diagnosing Mesothelioma
Mesothelioma develops in the linings of organs, frequently the lungs (pleura). It is strongly linked to asbestos exposure. Unlike many cancers, it doesn’t always form solid tumors; instead, it spreads as diffuse fluid across lung tissue, making it hard to detect by standard imaging. Approximately 30,000 cases are diagnosed worldwide annually, but the true number may be higher due to diagnostic limitations.
How the New Test Works
Researchers at Georgetown and Johns Hopkins have developed a highly sensitive blood test that looks for circulating tumor DNA (ctDNA). Cancer cells shed DNA into the bloodstream, and this method can detect even microscopic traces of cancer missed by scans. The test uses advanced genome-wide sequencing to identify the presence of ctDNA, even in mesothelioma, which has historically been hard to detect using these methods.
The Study Findings
The phase II clinical trial, led by Dr. Joshua Reuss, tested this approach on patients who might benefit from surgery. The study found that the blood test:
- Detected cancer in patients where imaging showed no clear signs of disease.
- Predicted relapse rates more accurately than standard assessments.
- Showed promising signals for improving outcomes with neoadjuvant immunotherapy (treatment before surgery).
“Imaging doesn’t always capture what’s happening with mesothelioma, especially during treatment,” said Dr. Valsamo Anagnostou, senior author of the study. “By using an ultra-sensitive genome-wide ctDNA sequencing method, we were able to detect microscopic signs of cancer that imaging missed and predict which patients were most likely to benefit from treatment or experience relapse.”
Why This Matters
Early detection is crucial for improving survival rates. Mesothelioma is notoriously difficult to treat, but immunotherapy has shown promise in extending patient lives. This new blood test could help identify patients who would benefit most from immunotherapy before surgery, making treatment more effective.
The Future of Mesothelioma Diagnosis
While this study shows strong potential, further research is needed before the test can be widely adopted. Phase III trials will be crucial to confirm the benefits in larger patient groups. However, the early results suggest a significant shift in how mesothelioma is diagnosed and treated. The test is not yet ready for routine clinical use, but it represents a major step toward personalized medicine in cancer care.
The study was sponsored by Bristol Myers Squibb and supported by multiple grants, including those from the Department of Defense and the National Institutes of Health. Authors report financial ties to pharmaceutical companies, including AstraZeneca, Roche, and Merck, as disclosed in the published manuscript.
