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What is A biopsy from a mass in the neck region revels the presence of parafollicular cells. Which of the following is the best marker for the follow up of this patient? and explain in detail?
Medullary Ca Arises from parafollicular cells or 'C' cells Associated with secretion of calcitonin. Associated with amyloid deposition. Standard marker is Calcitonin. In calcitonin negative medullary thyroid Ca - Tumor marker is carcinoembryonic Ag Familial medullary thyroid carcinomas In MEN-2 Associated with germline RET mutations-Constitutive activation of the receptor. RET mutations are also in nonfamilial (sporadic) medullary thyroid cancers.