This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Medicine
[{'content': 'What laboratory test is most appropriate for this patient? \nSelect and explain. \nA. Alpha-fetoprotein, B. Beta2-microglobulin, C. Calcitonin, D. Insulin-like growth factor-1', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Answer C. CalcitoninThis patient had multiple flesh-colored papules on the eyelids, lips, and tongue. This phenotype is suggestive of multiple endocrine neoplasia (MEN) type 2B (MEN-2B), an autosomal dominant condition characterized by medullary thyroid cancer among other features. Serum calcitonin can be used to screen for medullary thyroid cancer.', 'role': 'assistant'}]