The five lung cancer blood tests refer to the five lung cancer tumor markers, and the test items and normal range of values are slightly different in different medical institutions. The normal range is less than 5 μg/L; 5, cytokeratin 19 fragment, the normal range is less than 3.3 μg/L. Mild elevation of a single tumor marker is not very meaningful clinically; if multiple indicators are significantly elevated at the same time, combined with the patient’s relevant imaging examination, we can determine whether lung cancer occurs and the specific relevant pathological type. Which one it tends to be, can provide relevant basis.