MIA of the lung refers to microinvasive lung adenocarcinoma, a type of non-small cell lung cancer. Lung adenocarcinoma is a common type of lung cancer. Clinically, it is further classified into lung adenocarcinoma in situ, microinvasive lung adenocarcinoma, and invasive lung adenocarcinoma according to the severity of tumor infiltration. Microinvasive lung adenocarcinoma refers to lung cancer that invades more than the basement membrane of epithelial cells, but the infiltrated area under microscope does not exceed 5mm. Microinvasive lung adenocarcinoma usually does not develop regional lymph node and distant metastasis, and whether it is metastatic or not needs to be judged by perfect examination. Surgery is the main treatment for microinvasive lung adenocarcinoma. Whether postoperative chemotherapy, targeted therapy or radiotherapy is needed needs to be judged by the doctor according to the stage of the disease and the specific condition of the patient. If you have microinvasive lung adenocarcinoma, you should improve the examination under doctor’s guidance to evaluate whether there are metastases in other parts of the body and make appropriate treatment plan to improve the prognosis and treatment as soon as possible.