CEACAM5 and metastatic malignant neoplasm in the lymph nodes: On the other hand, in the group that included patients without lymph node metastasis (n = 76), the sensitivity of ctDNA, CEA, and combination of both ctDNA and CEA were 69.7% (53/76), 75.0% (57/76), and 85.5% (65/76), respectively.