This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': 'Which of the following is the best marker to distinguish Thymoma from lymphoma? \nSelect and explain. \nA. CD19, B. Cytokeratin, C. CD79a, D. Laminin', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Both thymoma and Lymphoma are common mediastinal tumors. But Thymoma has both Lymphocytic & Epithelial Component. Hence "Cytokeratin" which is a epithelial cell marker is best to distinguish it from Lymphoma.', 'role': 'assistant'}]