Calcitonin Revisited in 2020

Abstract

Calcitonin (CT) is a polypeptidic hormone specifically secreted by the thyroid parafollicular cells (C cells) and tangentially involved in human phosphocalcic and bone metabolism. CT from other species (e.g. salmon) is more potent than human CT and has limited therapeutic applications. The neoplastic proliferation of C cells leads to medullary thyroid carcinoma (MTC) generally characterized by an increase of CT secretion. Serum CT is therefore the ideal marker for MTC and can confirm its presence at an early stage, as well as the follow up of its remission or progression/relapse/survival after surgery. There are, however, controversies such as the necessity of CT screening in patients with thyroid nodules, or particular situations causing false positive or false negative results. Our minireview also deals with an up-to-date of surgical procedures for MTC, as well as with non-surgical therapy.

The value of routine measurement of serum calcitonin on insufficient, indeterminate, and suspicious thyroid nodule cytology

“…Although the detection of MTC through routine calcitonin screening has recently been shown to lead to early stage diagnosis, the American Thyroid Association (ATA) guideline did not make recommendations for routine calcitonin measurement in nodular thyroid patients, leaving the decision up to the clinicians (13). However, many authorities recommend routine serum calcitonin measurement in nodular thyroid disease (4,9,10,17,19,20), but this recommendation is very controversial since it is considered that thyroid nodule prevalence is 33-68% (6,(21)(22)(23). In addition, the prevalence of MTC in nodular thyroid disease is unknown, and in thyroid cancers, its prevalence has been found to be 1-2% (1).…”

“…The production of calcitonin, a 32 amino acid long polypeptide hormone, is a characteristic feature of this tumor. Therefore, calcitonin measurement plays an important role in both diagnosis and follow-up of MTC patients (5,6) Many studies have shown that routine measurement of serum calcitonin may lead to earlier detection of MTC in patients with thyroid nodules (4,(7)(8)(9)(10)(11)(12). The American Thyroid Association (ATA) has remained neutral on the subject of routine calcitonin measurement in thyroid nodule follow-up, leaving the decision up to the clinicians (13).…”

Diagnostic Challenges of Medullary Thyroid Carcinoma

“…The serum Ctn level is generally proportional to tumor involvement, and lower than expected readings should raise suspicion for factors affecting the laboratory assay. In general, values <10 pg/mL are reassuring for no C-cell disease, 10-100 pg/mL indeterminate, 100-500 pg/mL Ccell hyperplasia or early MTC, 500-1,000 pg/mL with metastatic disease, and greater than 1,000 pg/L for distant metastasis (Table 3) [15,25].…”

Determinantes de la densidad mineral ósea y el papel del ejercicio físico con cargas en personas mayores

“…Estas hormonas sexuales tienen una función de evitar la osteoclastogénesis, inhibir el proceso de apoptosis de osteoblastos y osteocitos, y evitar la formación de osteoclastos, lo que regula positivamente la OPG en la vía de señalización celular RANK/OPG (Figura 3) (46) . La calcitonina es una hormona secretada por las células parafoliculares de la glándula tiroides (48) , en respuesta al aumento de calcio sérico (49) . Esta hormona actuaría al disminuir la reabsorción de calcio en el riñón (19) y al inhibir la formación ósea a través de la reducción en la liberación de la esfingosina-1-fosfato (SP1) por los osteoclastos (50) .…”