The Epi-TOP LUNG assay is a product developed based on the Epi-TOP methylation detection method, the epigenetic testing source technology of Seebiomaterials, and a cancer-specific epigenetic panel. The Epi-TOP LUNG assay diagnoses lung cancer by analyzing the DNA methylation patterns of seven biomarkers related to lung cancer in exosomes extracted from bronchoalveolar lavage fluid (BALF).