Two years ago, 27-year-old Ms. Chen was hospitalized in our department with coughing symptoms, and was initially diagnosed with pneumonia when she saw a patchy shadow in her right lung on a radiograph, but later the result was a malignant lung tumor (lung cancer). This year, another “post-80s” patient was hospitalized in our department because of cough symptoms and was found to be a lung malignant tumor. …… Lung cancer was previously thought to be a disease suffered only by the elderly, and few young people were found to suffer from this disease, but the situation has completely changed. Nowadays, the situation has completely changed, many young people are also suffering from lung cancer, and the trend of lung cancer is becoming younger. What are the reasons for this trend? First of all, the main reason is poor lifestyle, of which smoking and passive smoking are the most critical factors. Children and adolescents suffer the most from passive smoking because their organs are immature and delicate, and their resistance to harmful factors in the external environment is low. Serious consequences. Secondly, the increasingly serious environmental pollution, high PM2.5 and poor indoor air quality are also the main reasons for the rise of lung cancer. So what warning can be given to us by the youthfulness of lung cancer? First of all, one should avoid poor lifestyle. Do not smoke, drink less, adjust the diet structure and eat more green fruits and vegetables. Secondly, we should avoid passive smoking and reduce indoor air pollution such as kitchen fumes and formaldehyde. As young people need to take the initiative to stay away from the environment of “second-hand smoke”. On the other hand, we should improve the kitchen ventilation, exhaust fumes, change the wrong cooking method, and improve the living environment and promote green home decoration. Finally, young people should pay attention to health checkups. Especially for those who have a history of smoking or a long history of passive smoking, regular health checkups are recommended. They should be highly alert to common symptoms of lung cancer, such as cough, hemoptysis and persistent chest pain, and seek medical consultation in time to minimize the threat of lung cancer to health.