<prompt> Which of the following is not true regarding Medullary Ca thyroid?HereditarySecrets calcitoninHormone dependantAmyloid stroma  <response>: Medullary thyroid cancer MTC originates from the parafollicular cells C cells, which produce the hormone calcitonin. Approximately 25 of medullary thyroid cancer is genetic in nature, caused by a mutation in the RET proto-oncogene. When it coexists with tumors of the parathyroid gland and medullary component of the adrenal glands pheochromocytoma it is called multiple endocrine neoplasia type 2 MEN2. The majority of C cells are located at the junction of the upper third and lower two thirds of the thyroid gland; hence, this is the most common location of MTC. On FNAC, MTC is characterized by the presence of stromal amyloid and the absence of thyroid follicles. 