EGFR and neoplasm: Based on this, this study divided patients with lung adenocarcinoma into brain metastasis group and anencephaly metastasis group, and screened out indicators that may be related to lung adenocarcinoma brain metastasis, such as gender, age, tumor TN stage, serum tumor markers, EGFR mutation status, etc., and included indicators with few previous studies or still controversial indicators, such as lymphocyte percentage, neutrophil-to-lymphocyte ratio, lactate dehydrogenase, etc., to explore the risk factors for lung adenocarcinoma brain metastasis.