The symptoms of mid-stage lung cancer are as follows: First, it is coughing and coughing sputum, occasionally with blood in sputum, shortness of breath, which is aggravated after activity. If it is accompanied by superior vena cava compression, there will be swelling of face and swelling of both upper limbs. Second, there is the condition of chest pain, which appears to have cough and chest pain, especially after strenuous activities, which is obviously aggravated. Secondly, there are symptoms of bone metastasis, which can appear as back pain and numbness of the limbs after activity. Other symptoms include metastasis to the head, which may cause headache, vomiting and even limb convulsions. Therefore, the intermediate symptoms of lung cancer depend on, firstly, the local symptoms of lung; secondly, whether there is distant metastasis.