If 1.5 cm nodule is found in mediastinum after lung adenocarcinoma surgery, it may be a phenomenon of metastasis, and it is necessary to determine the nature of the nodule through enhanced CT, pathological biopsy and so on. Lung adenocarcinoma surgery has a certain chance of recurrence. If a 1.5 cm nodule is found in the mediastinum, the nature of the nodule needs to be determined by CT, pathological biopsy and so on. If it is malignant, it means that the patient has already had metastatic spread; if it is benign, it is not a metastatic phenomenon, but just a simple benign disease. If mediastinal metastasis occurs after lung adenocarcinoma surgery, as long as it meets the indication of surgery, it needs to be resected in time; if it cannot be operated, it needs to be treated with local radiotherapy, chemotherapy or targeted therapy.