LIF and metastatic malignant neoplasm in the lymph nodes: Leukemia inhibitory factor (LIF) serves as a more effective biomarker compared to carcinogenic embryonic antigen (CEA) and carbohydrate antigen 19-9 (CA 199), with case studies indicating high LIF expression in patients with lymph node metastases, correlating with decreased overall survival and recurrence-free survival [58,59].