<prompt> Tumor marker for medullary carcinoma of thyroid is:AlbuminTSHThyroglobulinCalcitonin  <response>: Ans. d CalcitoninRef: Bailey and Love 26th ed. ch. 51 764 Medullary thyroid cancer is a rare form of thyroid cancer and accounts for 3 to 10 of all thyroid cancers. It grows from specialized thyroid cells called parafollicular cells. Parafollicular cells-C-cells; specialized thyroid cells that secrete calcitonin and play a major role in diagnosis of medullary thyroid cancer. 