Generally speaking, lung cancer is characterized by high density on the image.
Normally, normal lungs contain a lot of gases and their density is relatively small, while cancerous tissues show higher density on the image, so the density of normal lung tissues is smaller than that of cancerous tissues, thus lung cancer usually shows high-density shadow on the image.
Therefore, if high density shadow is found in the examination, attention should be paid to it. The high density shadow of lung cancer manifests irregular shape, unclear boundary and adhesion with surrounding tissues, which need to be further examined by enhanced CT, checking whether there is any abnormality of blood tumor marker, bronchoscopy and puncture biopsy to make clear whether it is lung cancer or not.