Calcitonin level

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. 

S. Hoegerle, C. Altehoefer, N. Ghanem, I. Brink, E. Moser, E. Nitzsche, F-DOPA positron emission tomography for tumor detection in patients with medullary thyroid carcinoma and elevated calcitonin levels, Eur. J. Nucl. Med. 28(1) (2001) 64-71. 

Nasal absorption. Sucrose ester of coconut fatty acid in aqueous ethanol solution (sucrose cocoate SL-40) administered intrana-sally to anesthetized male Sprague-Dawley rats at a dose of 0.5% sucrose cocoate with insulin, produced a rapid and significant increase in plasma insulin level with a concomitant decrease in blood glucose levels. Administration of a dose of 0.5% sucrose cocoate with calcitonin produced a rapid increase in plasma calcitonin levels and a concomitant decrease in plasma calcium levels . 

Calcitonin levels appear to correlate with such indicators of extent of disease as tumor volume and tumor involvement in local and distant metastases. Calcitonin is useful for monitoring treatment and detecting the recurrence of disease. 

Calcitonin levels are also elevated in some patients with carcinoid and cancer of the lung, breast, Iddney, and liver. The usefulness of calcitonin as a tumor marker in these malignancies has not been proven. Calcitonin elevation has been reported in other nonmahgnant conditions, such as pulmonary disease, pancreatitis, hyperparathyroidism, pernicious anemia, Pagefs disease of bone, and pregnancy. 

Becker ICL, Nash D, Silva OL. Increased serum and urinary calcitonin levels in patients with pulmonary disease. Chest 1981 79 211-6. 

Body II, Chanoine IP, Dumon JC, Delange F. Circulating calcitonin levels in healthy children and subjects with congenital hypothyroidism from birth to adolescence. J Endocrinol Metab 1993 77 565-7. 

Klein GL, Wadington EL, Collins ED, Catherwood BD, Deftos LJ. Calcitonin levels in sera of infants and children relations to age and periods of bone growth. Calcif Tissue Int 1984 36 635-8. 

Pedrazzoni M, Mantovani M, Ciotti G, Girasole G, Pioli G, Palummeri E. Calcitonin levels in normal women of various ages evaluated with a new sensitive radioimmunoassay. Horm Metab Res 1988 20 118-9. 

Rude RK, Singer FR. Comparison of serum calcitonin levels after a 1-minute calcium injection and after pentagastrin mjection in the diagnosis of medullary thyroid carcinoma. J Clin Endocrinol Metab 1977 44 980-3. 

Tisell LE, Dilley WG, Wells SA Jr. Progression of postoperative residual medullary carcinoma as monitored by plasma calcitonin levels. Surgery 1996 119 34-9. 

Serum thyroid-stimulating hormone (TSH) and thyroid hormone levels should be measured in any patient with a goiter to determine the hormonal status. TSH concentrations increase with age, but the levels remain within the normal range in the healthy population throughout life up to 100 years of age (Canaris et al., 2000 Mariotti et al, 1995). See Chapter 106 by Diez and Iglesias on Hypothyroidism in the Middle Aged and Elderly Clinical Aspects for details of thyroid hormone changes in the elderly. Serum calcitonin levels are not needed unless there is a family history of medullary thyroid cancer or multiple endocrine neoplasia (MEN) type 2. 

Nishiyama S, Nakamura T, Higashi A, et al. 1991. Infusion of zinc inhibits serum calcitonin levels in patients with various zinc status. Calcif Tissue Res 49(3) 179-182. 

The patient was placed on an essentially purine-free diet and received no medication for 5 days. Uric acid metabolism disclosed uricemia 2.0 mg/dl uricosuria 510 mg/day Cur 15.4 ml/min Ccr 91 ml/min fractional excretion of uric acid (Cur/Ccr) 16.9%. Basal plasma calcitonin was 168 pg/ml (normal values undetectable). A pentagastrin bolus injection of 0.5 g/Kg elevated plasma calcitonin over 1000 pg/ml. Simultaneously, serum uric acid decreased from 2.0 mg/dl to 1.3 mg/dl, and Cur/Ccr increased from 16.9% to 25.7%. A pentagastrin test in two control subjects did not make plasma calcitonin levels detectable, nor did it modify uric acid excretion. Her clinical course was progressively down-hill and she died after several bronchoneumonic episodes and massive tracheal hemorrage. Pyrazinamide and probenecid tests could not be done. Permission for autopsy was denied. 

The malignant disease of our patient could not be accui ately established. Nevertheless, her basal calcitonin level was very high and pentagastrin raised calcitoninaemia, at least, 495%. This fact consistently supports the diagnosis of MCT, instead of ectopic calcitonin secretion. 

Fig. 34.3. FDOPA images (CT on the left, fused images in the middle, and whole-body PET [MIP] on the right) of a patient after thyroidectomy for medullary thyroid carcinoma (6 years ago), actually presenting with elevated calcitonin levels. PET shows pathologically increased uptake in a normal sized cervical lymph node (upper row) and in two lesions within the thyroid bed Surgery confirmed local recurrence of MTC and lymph node metastasis in this patient. Calcitonin levels normalized following surgery...

Monitoring Therapy A high-dose calcium test may be used as a potent biomarker for the diagnosis and follow-up of medullary thyroid cancer (MTC), since it is well tolerated and is cost effective compared to the pentagastrin test. A recent study identified that the best levels of basal calcitonin (bCT) to distinguish normal and C-cell hyperplasia (CCH) cases, from MTC patients were above 18.7pg/ml in females and above 68pg/ml in males while calcium-stimulated calcitonin levels above 184 pg/ml in females and above 1620pg/ml in males were most accurate to separate normal and CCH cases from patients with MTC [74 ]. 

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