Medullary carcinoma of the thyroid gland: Use of biochemical parameters in detection and surgical management of the tumor

Medullary thyroid carcinoma is a relatively rare tumor which arises from the parafollicular cells in the thyroid gland. The lesion may occur sporadically or as a familial disease inherited in a Mendelian dominant pattern. The inherited form is often associated with pheochromocytoma and hyperparathyroidism (Sipple's syndrome). Medullary carcinoma is an aggressive tumor with the ability to metastasize widely, and early surgical cure must be provided. Measurements of 2 tumor associated products, calcitonin and histaminase activity, are essential to the overall management of patients with this disease. Blood calcitonin levels provide an extraordinarily sensitive index for presence of the tumor, even in its earliest stages, allowing for early surgical intervention in familial disease. Elevated blood histaminase activity may be a sign of metastatic disease and of recurrent or residual disease in the postoperative setting. A scheme for management of medullary thyroid carcinoma patients, including the use of biochemical markers and the surgical approach currently suggested, is discussed.