Medullary thyroid carcinoma refers to the cancer that affects the thyroid gland starting from the cells that produce a hormone known as calcitonin (Tuttle). The location of the gland is inside the front part of the neck and the cells producing the hormone are referred to as C cells. The pattern of growth of the medullary carcinoma is a bit slow but progressive and usually invades structures that are adjacent. The spreading of the tumor is hematogenous with metastases occurring typically to bone, lymph nodes, as well as the lung. There is variability on the clinical progression of medullary thyroid carcinoma (Shoback and Sellmeyer).
Although chances of early metastases to mediastinal and cervical lymph nodes are high in almost 70% of patients, the behavior of the tumor is, usually, in an indolent fashion. In minor cases, there has been a more aggressive pattern that has been noted. Detection of the cancer early enough in individuals who are at a high-risk such as those who have a family history of MEN-2A, medullary carcinoma or MEN-2B may play a vital role in the prevention of disease advancement. The detection may also help in preventing distance metastases. In all cases, survival rate is estimated at 80% within the first five years and 60% within ten years. Younger individuals have a greater survival rate compared to older individuals (Shoback and Sellmeyer).
In most cases, C-cell hyperplasia occurs before cancer can develop, and this enables for premalignant detection, as well as prophylactic thyroidectomy consideration. Medullary thyroid carcinoma may also result in chronic hyper-calcitoninemia, which may contribute to the parathyroid hyperplasia pathogenesis. However, cases of parathyroid hyperplasia are not easily seen in individuals suffering from either medullary carcinoma or MEN-2B (Shoback and Sellmeyer).
Work Cited
Shoback DM, Sellmeyer DE. Disorders of the Parathyroids & Calcium & Phosphorus Metabolism. In: Hammer GD, McPhee SJ. Eds. Pathophysiology of Disease: An Introduction to Clinical Medicine, Seventh Edition. New York, NY: McGraw-Hill; 2013. http://accessmedicine.mhmedical.com/content.aspx?bookid=961&Sectionid=53555698.
Tuttle, Michael. Medullary thyroid cancer: Clinical manifestations, diagnosis, and staging. 2014. Online. 1 October 2014. <http://www.uptodate.com/contents/medullary-thyroid-cancer-clinical-manifestations-diagnosis-and-staging?source=see_link&anchor=H6#H10>.
