What is the first and most critical question asked by doctors for patients with middle to late stage lung cancer? For patients who are suspected to have middle or late stage lung cancer and come to the doctor for consultation, the doctor will usually ask a lot of questions, and the first and most crucial question is whether the patient has been smoking for a long time. This question seems to be simple, but in fact, it is not just about getting the patient to quit smoking. Whether smoking or not determines the type of lung cancer and the direction of subsequent treatment. The majority of long-term smokers (excluding patients who have quit smoking for more than 5-10 years) have lung cancers that are usually directly related to smoking, and the pathologic types include squamous, adenocarcinoma, and small-cell lung cancers. 95% of these patients have no treatable mutations, and there is no opportunity for these patients to receive current targeted therapies. The primary goal for these patients is to make a definitive pathologic diagnosis and, if physically able to tolerate it, to undergo chemotherapy combined with immunotherapy as soon as possible. 2.Never smokers, occasional smokers, or patients who have quit smoking for more than 10 years, the lung cancer of these patients usually has little relationship with smoking, and many of them have lung cancer due to tumor gene mutation. The primary goal of these patients is to clarify the pathological results and the results of the gene mutation test, and if there is a gene mutation, the first choice is to use targeted therapy at the corresponding mutation site. If there is no gene mutation, then chemotherapy combined with immunotherapy will be considered. Therefore, the question of whether or not to smoke, although simple, very clearly outlines the general direction of late treatment for patients with intermediate and advanced lung cancer.