<prompt> In Medullary Carcinoma thyroid Tumour marker is?TSHCalcitoninT3, T4 and TSHAlpha Feto protein  <response>: Ans is B ie calcitonin Schwaz Surgery writes ? The presence of amyloid is a diagnostic finding, but immunohistochemistry for calcitonin is more commonly used as a diagnostic tumor marker. These tumors also stain positive for CEA Carcinoembryonic antigen and CGRP Calcitonin gene-related peptide 