This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Testicular Tumors, Subject name: Pathology
[{'content': 'Which of the following is not used as a tumour marker in testicular tumours? \nSelect and explain. \nA. AFP, B. LDH, C. HCG, D. CEA', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Testicular Tumors often secrete polypeptide hormones and ceain enzymes . Biological markers include HCG, AFP, and lactate dehydrogenase, which are valuable in the diagnosis and management of testicular cancer. Elevation of lactate dehydrogenase , provides a tool to assess tumor burden. Marked elevation of serum AFP or HCG levels are produced by yolk sac tumor and choriocarcinoma elements, respectively. CEA ( Carcinoembryonic antigen ) is used as a tumor marker for many cancers like colorectal cancer but not testicular tumors.', 'role': 'assistant'}]