(Barcelona, Spain September 9, 2025, 10:15 a.m. CEST / UTC +2) — A new study presented at the International Association for the Study of Lung Cancer 2025 World Conference on Lung Cancer (WCLC) demonstrates that monitoring circulating tumor DNA (ctDNA) can refine and personalize the use of consolidation immunotherapy in patients with limited-stage small cell lung cancer (LS-SCLC).
The research, led by scientists at the National Cancer Center of China, assessed ctDNA in 177 patients with LS-SCLC treated with chemoradiotherapy (CCRT), 77 of whom received consolidation immune checkpoint inhibitors (ICIs). Circulating tumor DNA was measured at multiple time points to evaluate its ability to predict survival outcomes and immunotherapy benefits.
“This is the first study to show that early ctDNA detection after induction chemotherapy can help identify patients who are more likely to benefit from consolidation immunotherapy,” said Dr. Nan Bi, from the Chinese Academy of Medical Sciences. “It’s a step toward precision immunotherapy in limited-stage SCLC.”
Key Findings:
The study used next-generation sequencing (NGS) with a 139-gene lung cancer panel to assess ctDNA at ultra-deep coverage (30,000×). Advanced statistical models including time-dependent Cox regression were employed to eliminate immortal time bias.
“These findings offer a compelling rationale for integrating ctDNA-based stratification in future LS-SCLC trials and may help guide real-time decisions on the use of consolidation ICIs,” Dr. Bi said.
About the IASLC:
The International Association for the Study of Lung Cancer (IASLC) is the only global organization dedicated solely to the study of lung cancer and other thoracic malignancies. Founded in 1974, the association's membership includes more than 10,000 lung cancer specialists across all disciplines in over 100 countries, forming a global network working together to conquer lung and thoracic cancers worldwide. The association also publishes the Journal of Thoracic Oncology, the primary educational and informational publication for topics relevant to the prevention, detection, diagnosis, and treatment of all thoracic malignancies. Visit www.iaslc.org for more information.
About the WCLC:
The WCLC is the world’s largest meeting dedicated to lung cancer and other thoracic malignancies, attracting nearly 7,000 researchers, physicians, and specialists from more than 100 countries. The goal is to increase awareness, collaboration and understanding of lung cancer, and to help participants implement the latest developments across the globe. The conference will cover a wide range of disciplines and unveil several research studies and clinical trial results. For more information, visit https://wclc.iaslc.org/.