Carcinoembryonic antigen (CEA) is one of the most commonly used serum tumor markers in metastatic breast cancer, which normally implies poor overall survival (OS), disease-free survival (DFS), and a higher tumor burden such as lymph node metastasis, advanced TNM stage, and larger tumor size39, 167. This evidence concerns the gene CEACAM5 and metastatic malignant neoplasm in the lymph nodes.