Calcitonin is a hormone secreted by the thyroid gland cells and is involved in regulating the exchange of calcium and phosphorus in the body.

Function of Calcitonin:
Calcitonin has an antagonistic function to parathyroid hormone, which is formed in the parathyroid glands. The hormone promotes the active flow of calcium from the blood serum into the bone, increasing its density, and inhibits the reverse process – bone resorption. In the normal state, calcitonin and parathyroid hormone are ideally balanced to maintain a normal concentration of calcium in the blood and bone.

Diagnosis and Role in Cancer Detection:
Medullary thyroid cancer can be diagnosed early based on the hormone concentration level in the blood. Pathological changes affect “C cells,” causing them to intensively function. As a result, the calcitonin content increases, so any deviation from the normal state raises suspicions primarily of cancer. It is not enough to diagnose cancer from a single blood analysis, as physiological fluctuations in the hormone can be observed during pregnancy or in older adults. Cancer can only be confirmed after a series of diagnostic procedures, including laboratory tests, ultrasound, and radiographic examination of the gland, among others.

Calcitonin, thyrocalcitonin, TC, human calcitonin, thyroidal calcitonin, CT.

Indications for Analysis:

Determining the level of calcitonin in the blood is recommended in the following cases:

  • Suspected osteoporosis (with bone deformities, fractures, and high bone density).
  • Disorders of phosphorus and calcium metabolism.
  • Suspected multiple endocrine neoplasia syndrome (may include medullary thyroid cancer, pheochromocytoma, and/or parathyroid gland enlargement with hormone autoimmunity).
  • Suspected malignant formations in the thyroid gland.
  • Thyroid nodules and organ enlargement.
  • Pheochromocytoma or suspicion thereof.
  • Preparation for tumor surgical excision.
  • The study is also conducted as part of a comprehensive examination for individuals with relatives who have medullary thyroid cancer.

Methods of Examination:
The study is conducted using the solid-phase enzyme immunoassay technique (also known as the “sandwich” method). The patient should donate a sample of venous blood.
Preparation for Sample Collection:
Recommendations for preparing for blood calcitonin level analysis include:

  • Fasting for at least 12 hours before the procedure, as blood is taken on an empty stomach.
  • Exclude spicy and fatty foods from the diet the day before the test.
  • Discontinue oral contraceptive pills for a month before the test.
  • Attempt to avoid emotional stress and excessive physical activity the day before the procedure.
  • Stop smoking 2-3 hours before sample collection.