This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thyroid, Subject name: Surgery
Treatment of Medullary carcinoma of thyroid is 
Select and explain. 
A. Surgery and Radiotherapy, B. Radiotherapy and Chemotherapy, C. Surgery only, D. Radioactive ablation
C: Surgery only
Answer: C: Surgery only 
Explanation: Management Total thyroidectomy + Routine central lymph node dissection + ipsilateral modified radical node dissection (Tumor > 1cm) +- Bilateral modified Radical neck dissection (if any lymph node is positive) MCT - Poor prognosis (because it does not respond to radioactive iodine ablation) Vandetanib - Only FDA approved drug in advanced progressive medullary thyroid cancer.