As people pay more attention to their health, regular medical checkups are becoming an increasingly popular choice. Chest X-ray is an essential part of regular medical checkups. When a chest X-ray indicates a shadow in your lung, is it assumed that you have lung cancer? Undeniably, the most common manifestation of lung cancer on chest X-ray is indeed a shadow in the lung. However, in fact, there are many other diseases that show up as shadows on chest radiographs besides lung cancer, from inflammatory lesions such as pneumonia, lung abscess and tuberculosis, to benign tumors such as malignant tumors and lipomas, to some congenital developmental malformations such as pulmonary segregation and pulmonary arteriovenous fistula, all of which can show up as lung shadows of different shapes. Sometimes, external ornaments that have not been removed can also appear as lung shadows. Therefore, when a chest X-ray suggests a shadow on your lung, you should not panic, but bring the X-ray to the relevant specialized clinic and listen to the guidance of the relevant professional physician, in order to make a clear diagnosis as soon as possible.