Increased white sputum 6 months after surgery for squamous lung cancer may be caused by postoperative infection, pleural effusion, bronchial damage, recurrent lung metastasis. 1. Postoperative infection: postoperative infection due to poor postoperative care and other reasons, resulting in increased sputum 6 months after lung squamous carcinoma surgery. Clinically, it mainly manifests as coughing sputum, fever and other symptoms. 2. Pleural effusion: postoperative pleural effusion of squamous lung cancer will compress the lungs and stimulate the airway, thus causing coughing up white sputum, and the symptoms will be relieved after puncture and fluid extraction. 3. Damaged bronchial tubes: local damage to bronchial tubes may be caused during surgery for squamous lung cancer, resulting in bronchitis. When patients suffer from bronchitis, the phenomenon of increasing white sputum 6 months after operation will occur, and sometimes it will cause bronchospasm, shortness of breath and chest tightness. 4. Lung cancer recurrence and metastasis: recurrent metastatic foci block the trachea or bronchus, forming obstructive pneumonia, which will also show the symptom of increased white sputum. Therefore, when patients with squamous lung cancer have increased white sputum 6 months after surgery, they should consult a doctor in time, and under the guidance of a professional doctor, correctly judge the treatment.