Clinically microinvasive lung adenocarcinoma does not have micropapillary type present, and invasive adenocarcinoma has micropapillary type. Microinvasive adenocarcinoma is defined as a single lung lesion less than or equal to 3 centimeters, with cancer cells growing close to the alveolar walls and infiltrating the surrounding area by more than 0.5 centimeters. It usually does not infiltrate blood vessels, lymphatics, and pleura, nor does it necrose and spread to the respiratory tract. Invasive adenocarcinoma can be clinically categorized into 5 types: mucinous adenocarcinoma, endometrioid adenocarcinoma, clear cell adenocarcinoma, plasma adenocarcinoma, and mesonephric ductal adenocarcinoma, of which mucinous adenocarcinoma includes micropapillary type. It is recommended that patients with microinvasive lung adenocarcinoma should go to the hospital in time for early detection and early treatment.