The presence of 20mm burrs in lung nodules is not necessarily lung cancer, and should be judged by further pathological examination and other tests. Lung nodules are space-occupying lesions occurring in the lungs, which can be detected during chest CT and X-ray examination. Doctors will initially judge whether a lung nodule is benign or malignant according to the characteristics of the lung nodule in the CT and X-ray images, in which if there is a burr on the edge, it can be caused by benign nodules such as tuberculosis nodule or malignant nodules such as lung cancer, so the appearance of 20mm burr cannot be concluded as lung cancer. Lung cancer is the most common primary malignant tumor of the lungs, and the most accurate basis for diagnosing lung cancer is pathological examination. Pathological examination is a pathomorphologic method to examine pathological changes in organs, tissues or cells of the organism. It is suggested that when patients find nodules in the lungs with burrs on the edges, they should do pathological examination to judge them, and cannot judge them as lung cancer categorically.