Our univariate analysis of possible factors identified symptoms at presentation, GGO status, pleural involvement, serum CEA level (ng/mL), and pathologic type as predictors of nodal involvement in clinical stage T1a lung adenocarcinomas, whereas multiple variable analysis identified symptoms at presentation, GGO status, and abnormal CEA titer (>5 ng/mL) as important predictors of lymph node metastasis. The gene discussed is CEACAM5; the disease is metastatic malignant neoplasm in the lymph nodes.