Used in biomedical research to detect and quantify CYFRA 21-1, a soluble fragment of cytokeratin 19, in human serum or plasma samples. This kit is primarily applied in studies related to epithelial cell turnover and tissue damage, especially in lung cancer research. It serves as a tool for monitoring tumor progression, evaluating treatment response, and assessing recurrence in non-small cell lung cancer (NSCLC). The assay supports clinical investigations by providing a sensitive and specific measurement of CYFRA 21-1 levels, aiding in the identification of potential biomarkers for diagnosis and prognosis. Commonly used in laboratory settings for immunoassay-based analysis.