Inclusion Criteria:  1. Aged between 18 and 75 years; 2. Lung adenocarcinoma; 3. The patient is able to receive neoadjuvant pemetrexed and cisplatin chemotherapy 4 .The patient is able to understand and comply with the study and has provided written informed consent.  Exclusion Criteria:  1. Patients with a history of lung surgery; 2. Postoperative pathology showed non-primary lung cancer; 3. Patients with a history of other tumors; 4. Patients with severe complications (coronary heart disease, valvular heart disease, end-stage renal disease, severe liver cirrhosis); 5. Unable to cooperate with the researchers because of dementia or cognitive decline 6. Other situations that are not in conformity with the standards and requirements of this trial.