Medullary Thyroid Cancer
The thyroid is an endocrine organ. It is made of two lobes, connected by the isthmus.
The gland is made up of follicular cells, arranged in a spherical manner (follicles) that are filled with a substance called colloid.
The thyroid hormones (thyroxine [T4] and 3,5,3′-triiodothyronine [T3]) are synthesised by the follicular cells and controlled by thyrotropin-stimulating hormone (TSH) secreted from the anterior pituitary in response to thyrotropin-releasing hormone secreted by the hypothalamus.
T3/T4 activate the metabolism of many cells in the body, controlling heart rate, blood pressure, body temperature, and basal metabolic rate.
C-cells are found in the interstitium surrounding the follicles and secrete calcitonin. Calcitonin is involved in regulating the levels of calcium and phosphate in the blood.
Medullary Thyroid Cancer (MTC) originates from C-cells and is an orphan disease5. MTC can be inherited / hereditary (25% of cases) or sporadic / spontaneous (75% of cases).
The cause of most MTCs is a gene mutation (a change in genetic or DNA sequence) in the RET proto
oncogene. This leads to abnormal proliferation of C cells, and, in many cases, subsequent development of MTC.
The primary treatment for MTC is surgery to completely remove the thyroid (total thyroidectomy).
Once the disease is more advanced and/or with distant metastasis, the patient could be eligible to systemic treatment with oral tyrosine kinase inhibitors.
Learn more about this disease, its diagnosis and treatments.
1 Wells SA Jr, Asa SL, Dralle H, et al. American Thyroid Association Guidelines Task Force on Medullary Thyroid Carcinoma. Revised American Thyroid Association guidelines for the management of medullary thyroid carcinoma. Thyroid. 2015;25(6):567-610.
2 Carling, T. and Udelsman, R. (2011). Thyroid Tumors. In: V. DeVita, VT. Lawrence and TS. Rosenberg SA, ed., Cancer: Principles & Practice of Oncology, 9th ed. USA: Lippincott Williams and Wilkins, pp.1457-1472.
3 Hadoux JU, et al. Management of advanced medullary thyroid cancer; Lancet Diabetes Endocrinol. 2016; 4:64-71
4 Roman S, Lin R, Sosa JA. Prognosis of medullary thyroid carcinoma: demographic, clinical, and pathologic predictors of survival in 1252 cases. Cancer. 2006;107:2134–2142.
5 http://www.orpha.net/consor/cgi-bin/OC_Exp.php?Lng=EN&Expert=1332 Last accessed 28/12/2017