Lumbar Punctures for the Detection of ctDNA in the Cerebrospinal Fluid of Patients With Stage III and IV Non-Small Cell Lung Cancer

This phase I trial assesses the use of lumbar punctures to detect whether there is circulating tumor deoxyribonucleic acid (ctDNA) in the fluid that surrounds the brain and spinal cord (cerebrospinal fluid) in patients with stage III and IV non-small cell lung cancer (NSCLC). Patients with stage III and IV NSCLC are at risk of having their cancer spread from where it first started to the brain (metastatic). Because of this, more effective prognostic tools are necessary to determine which stage III and IV NSCLC patients are more likely to develop brain metastases. Cerebrospinal fluid (CSF) could be a reliable source of ctDNA to confirm and predict the presence of brain metastases in these patients. Assessing cell free DNA shed from tumor cells could be a sensitive and minimally invasive way to detect or characterize metastatic tumors in the central nervous system (CNS). Lumbar puncture is procedure in which a thin needle called a spinal needle is put into the lower part of the spinal column to collect CSF. Lumbar punctures for the collection of CSF may help doctors detect or measure changes in cell types, genes, and proteins of circulating tumor cells related to lung cancer that will help determine the presence of brain metastases which could become a standard of care screening tool utilized in the follow-up of patients diagnosed with stage II or IV NSCLC.