If a lung cancer patient cannot breathe, the first way to deal with it is to find the cause and then treat it according to the cause, as follows: 1. Lung cancer obstructs the airway: not being able to breathe is called dyspnea in medical terms. The treatment method is to use radiotherapy or install stents to unblock the airway so that air can enter the lungs.2. Lung tissue edema: If the lung tissue edema is caused by lung inflammation, it may also lead to dyspnea because of the obstruction of oxygen exchange. Pleural metastasis can lead to a large amount of pleural fluid, which may also compress lung tissue expansion and cause dyspnea. In conclusion, there are many causes of dyspnea caused by lung cancer, and the treatments for different causes are different, but the most fundamental solution is to use effective anti-tumor treatments to eliminate the cancer in order to fundamentally relieve the symptoms of breathlessness.