Many patients with chronic cough have a chronic cough, but this symptom is often overlooked by both doctors and patients or categorized as other causes. Especially with the poor air quality in China, cough symptoms are not too common and can easily be missed. If a patient’s cough persists for more than two or three weeks, it must be taken seriously. In addition to the need for differential diagnosis with respiratory allergies and respiratory infections, patients with asthma, chronic obstructive pulmonary disease (COPD), allergies, or gastroesophageal reflux who have cough symptoms due to their primary disease need to be carefully differentiated when diagnosing. Blood clots are also a common symptom of lung cancer, but they are not easily detected by the patients themselves and need to be brought to the attention of doctors. Shortness of breath on movement as another early symptom of lung cancer, this symptom is easily thought to be caused by old age, poor physical fitness or obesity. If patients feel shortness of breath during daily activities without cardiovascular disease, they need to be aware of lung cancer screening. Pain in the shoulder, back, chest and arm Lung tumors may compress nerves and cause pain in the patient’s shoulder, chest, back or arm – a symptom that may even precede coughing and shortness of breath. If painful symptoms occur in these areas without primary injury, especially painful symptoms that worsen with coughing and breathing, close attention is needed. Up to 50% of lung cancer patients have a chest or shoulder pain condition at the time of diagnosis. Recurrent infections (bronchitis and pneumonia) It is not uncommon for patients with recurrent pneumonia or bronchitis to be clinically diagnosed with lung cancer. If the tumor is close to the airway, it can cause obstruction making the patient more susceptible to lung infections. Long-term smoking or COPD can also cause lung infections and bronchitis, but these are also high risk factors for lung cancer. Abnormal symptoms or decreased physical fitness Sometimes even seemingly unrelated symptoms can be associated with lung cancer, especially in patients who smoke. For example, 1.7% of patients with non-small cell lung cancer experience knee pain in the early stages. In addition a combination of symptoms such as fatigue, loss of appetite, unexplained weight loss and even the onset of depression may indicate lung cancer. Statistics show that 25% of lung cancer patients are diagnosed with lung cancer without specific symptoms, and many are found only after a CT or X-ray for other reasons. Imaging is unfortunately not very effective in the early detection of lung cancer. However, recent studies have shown that CT screening can reduce mortality by 20% for certain patients, the limited range of these patients being those aged 55-74 years who smoke more than 30 packs per year. As well, for patients with a history of radon exposure and genetic susceptibility factors, CT scan also has screening significance. Currently, the number of lung cancer patients in China is in the growth phase for various reasons. Early screening is significant for the survival rate of patients, and attention to early clinical symptoms can save patients’ lives.