Medullary carcinoma of the thyroid

Methodology. Several radioimmunoassays of human calcitonin (hCT) have been developed In the past 5 years (18-20). Their greatest utility has been In the definitive diagnosis of patients with medullary carcinoma of the thyroid gland (MTC) and, recently. In Identifying family members of these patients who have occult MTC. 

L. J. Holtermuller, K. H. Arnaud, C. D. "Relations of Calcitonin and Gastrin in the Zollinger-Ellison Syndrome and Medullary Carcinoma of the Thyroid". N. Engl. J. Med. 

Sizemore, G. W. Heath, H. Ill "Immunochemical Heterogeneity of Calcitonin in Plasma of Patients With Medullary Carcinoma of the Thyroid". J. Clin. Invest. (1975), In Press. 

Early Diagnosis of Medullary Carcinoma of the Thyroid Gland... 

Although blood calcitonin levels are normally low, excessive levels have been found in association with medullary carcinoma of the thyroid and more rarely carcinoid tumors of the bronchus and stomach. Serum calcitonin levels are used to screen and monitor patients who have or are suspected of having medullary carcinoma of the thyroid. 

C) She may have medullary carcinoma of the thyroid. Therefore, serum calcitonin, ret-Pro-Oncogene determination, and ultrasound of the thyroid should be obtained. 

Medullary carcinoma of the thyroid Atrial amyloidosis Lysozyme amyloidosis Insulin-related amyloid Fibrinogen a-chain amyloidosis Synucleinopathies... 

Enolase is a glycolytic enzyme also known as phosphopyru-vate hydratase. Neuron-specific enolase (NSE) is the form of enolase found in neuronal tissue and in the cells of the diffuse neuroendocrine system and the amine precursor uptake, and decarboxylation (APUD) tissue. NSE is found in tumors associated with the neuroendocrine origin, including small cell lung cancer (SCLC), neuroblastoma, pheochromocytoma, carcinoid, medullary carcinoma of the thyroid, melanoma, and pancreatic endocrine tumors. 

Sisson JC, Gross MD, Frietas JE, Jackson CE, England BG. Combining provocative agents of calcitonin to detect medullary carcinoma of the thyroid. Henry Ford Hosp Med J 1981 29 75-80. 

Wells SA Jr, Bayiin SB, Linehan WM, Farrell RE, Cox EB, Cooper CW. Provocative agents and the diagnosis of medullary carcinoma of the thyroid gland. Ann Surg 1978 188 139-41. 

Calcitonin Neither deficiency nor excess of calcitonin is known to have any pathological effects. Plasma calcitonin is increased in the medullary carcinoma of the thyroid. Binds to cell-surface receptors in bone and kidney, increasing intracellular cAMP may also function by activation of phospholipase C signal transduction pathway, decreases Ca " " release from bone and stimulate Ca " " and phosphate excretion in kidneys, generally antagonistic to PTH. 

Calcitonin is a useful marker for medullary carcinoma of the thyroid, which occurs both sporadically and as a dominantly inherited disease. In this type of tumor, the plasma concentration of calcitonin is 1-1000 mg/mL (normal concentration ranges from undetectable to 0.05 ng/mL). Also, urinary hydroxyproline excretion is decreased. Ectopic secretion of calcitonin also occurs from several types of pulmonary tumor in addition to other hormones. 

In view of the known effects of adrenaline and noradrenaline on serum alkaline phosphatase activities of the dog (H12), it is surprising that reviews of pheochromocytomas barely mention this enzyme. High values may occur in this disorder because of such associated conditions as parathyroid adenomas (P2) or metastatic medullary carcinoma of the thyroid (S46) or, rarely, because pheochromocytomas may themselves metastasize to bone or liver (Jl). 

Sikri KL, Varndell IM, Hamid QA, et al. Medullary carcinoma of the thyroid An immunocytochemical and histochemical study of 25 cases using 8 separate markers. Cancer. 1985 56 2481-2491. 

Uribe M, Fenoglio-Preiser CM, Grimes M, Feind C. Medullary carcinoma of the thyroid gland Clinical, pathological and immunohistochemical features with a review of the literature. Am J Surg Pathol. 1985 9 577-594. 

Pentavalent Tc(V)-DMSA differs structurally and has been evaluated for imaging medullary carcinoma of the thyroid (Ohta et al. 1984 Ramamoorthy et al. 1987). The sensitivity of lesion detection is 95% no false positive uptake of Tc(V)-DMSA was seen in nine patients with a histologic diagnosis of medullary carcinoma. Accumulation of Tc(V)-DMSA was seen in both bone and soft tissue metastases. In comparison, 99mrpc-MDP detected all known metastases in bone, but none in soft tissue (Clarke et al. 1988). 

Bingham JB, and Maisey MN (1978) An evaluation of the use of " Tc-dimercaptosuccinic acid (DMSA) as a static renal imaging agent. Br J Radiol 51 599-607 Clarke SEM, Lazarus CR, Wraight P, Sampson C, Maisey MN (1988) Pentavalent " Tc-DMSA, MIBG, and " Tc-MDP. An evaluation of three imaging techniques in patients with medullary carcinoma of the thyroid. J Nucl Med 29 33-38... 

Fig 3 Calcium and pentagastrin provocation test of calcitonin secretion. There Is an exaggerated response to combined calcium and pentagastrin provocation in a patient with medullary carcinoma of the thyroid. 

HEN types 2 and 3 (MEN2. MEN3) are entirely distinct syndromes from MENl. MEN2 is most frequently characterized by medullary carcinoma of the thyroid gland. MEN3 resembles MEN2, although there are several differences. 

Pro)calcitonin (ACal) Res 14-18 (DFNKF) (Reches et al. 2002) Medullary carcinoma of the thyroid... 

Calcitonin Plasma Diagnosis of medullary carcinoma of the thyroid... 

The role of calcitonin in the pathogenesis of these diseases remains to be proven. It has been suggested that osteopetrosis is caused by an increased secretion of calcitonin in contrast, osteoporosis could be caused by a defect in calcitonin. Certainly some medullary carcinomas of the thyroid are associated with elevated levels of calcitonin and these tumors are not usually associated with osteopetrosis. The regulation of calcium levels in blood by parathormone and calcitonin is summarized in Fig. 5-14. For further information on the relationship between calcium metabolism and bone disease, read the book of Rasmussen and Bordier [38]. 

Mukherjee JJ, Kaltsas GA, Islam N,et al. (2001) Treatment of metastatic carcinoid tumours, phaeochromocytoma, paraganglioma and medullary carcinoma of the thyroid with (131)I-meta-iodobenzylguanidine [(131)I-mIBG]. Clin Endocrinol 55 47-60... 

A polypeptide hormone, consisting of 32 amino acids, produced in the C cells of the thyroid gland. It is involved in calcium homeostasis, its main action being to decrease osteoclastic activity and therefore reduce bone resorption. Calcitonin also has a phosphaturic effect. It is secreted in response to high ionized calcium levels. High serum levels are found in patients with medullary carcinoma of the thyroid. It is usually measured by radioimmunoassay. 

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