This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrine, Subject name: Pathology
[{'content': 'Which among the following is the most common thyroid cancer? \nSelect and explain. \nA. Papillary, B. Medullary, C. Follicular, D. Anaplatic', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans: a (Papillary Ca) Ref: Robbins, 7th ed, p. 1178Papillary Ca is the most common malignancy accounting for 80-90% of all cases followed by follicular Ca. thyroid. (10%).Remember the following facts about thyroid malignancies, they are extremely helpful...* Most common malignancy of endocrine system- Thyroid Ca* Most common malignancy thyroid-Papillary Ca* Most malignant- Anaplastic Ca* Least malignant- Papillary Ca* MC thyroid Ca after irradiation(Latent period = 30 yrs)- Papillary Ca* MC thyroid Ca in long standing MNG- Follicular Ca* Psammoma bodies seen in...- Papillary Ca* Orphan Annie nucleus seen in....- Papillary Ca* Thyroid Ca a/w dystrophic calcification-Papillary Ca* Thyroid Ca a/w amyloidosis- Medullary Ca* Thyroid Ca derived from 'c' cells- Medullary Ca* Thyroid Ca a/w MEN syndrome- Medullary Ca* Tumour marker for medullary Ca- Calcitonin* Tumour marker for papillary Ca-Thyroglobulin", 'role': 'assistant'}]