EGFR gene mutations are mainly in patients with advanced NSCLC, nonsmokers, lung adenocarcinoma patients, patients with lymph node metastasis, patients with high CEA expression, and patients with low Cy21-1 expression are more likely to develop EGFR mutation, and EGFR mutation patients have a better prognosis. The gene discussed is CEACAM5; the disease is metastatic malignant neoplasm in the lymph nodes.