Lung cancer is a leading cause of death worldwide, with 90% of cases caused by smoking. Only 20% of patients are suitable for surgery, and just 5% of all lung cancer cases survive for 5 years. Pulmonologists are medical specialists who treat diseases of the lungs and respiratory system, including lung cancer, pneumonia, asthma, and tuberculosis. They complete extensive medical training in internal medicine as well as conditions specific to the respiratory system.