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
Which type of thyroid carcinoma has the best prognosis - 
Select and explain. 
A. Papillary Ca, B. Anaplastic Ca, C. Follicular Ca, D. All
A: Papillary Ca
Answer: A: Papillary Ca 
Explanation: Ans is 'a' i.e., Papillary Carcinoma "In general pts. with PTC have an excellent prognosis with a greater than 95% 10-year survival rate." - Schwaz Papillary carcinoma of thyroid is a slow growing tumor, usually not associated with blood borne metastasis, and hence has a better prognosis than the other varieties. Follicular, Medullary and Anaplastic carcinomas are all associated with a greater incidence of blood borne metastasis and a poorer prognosis.