Calcitonin blood test
The calcitonin blood test measures the level of the hormone calcitonin in the blood.
How the Test is Performed
A blood sample is needed.
How to Prepare for the Test
There is usually no special preparation needed.
How the Test will Feel
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or slight bruising. This soon goes away.
Why the Test is Performed
Calcitonin is a hormone produced in C cells of the thyroid gland. Calcitonin helps control the building of bone.
The doctor may order a calcitonin test when you have symptoms of medullary cancer of the thyroid
or MEN syndrome
, or a family history of these conditions. Calcitonin may also be higher in other tumors, such as:
A normal value is less than 10 picograms per milliliter (pg/mL).
Women and men can have different normal values. Sometimes, calcitonin in the blood is checked several times after you are given a shot (injection) of a special medicine.
You will need this extra test if your baseline calcitonin is normal, but your doctor suspects you have medullary cancer of the thyroid.
Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different specimens. Talk to your doctor about the meaning of your specific test results.
What Abnormal Results Mean
A higher-than-normal level may indicate:
- Lung cancer
- Medullary cancer of thyroid (most common)
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight, but may include:
- Excessive bleeding
- Fainting or feeling light-headed
- Hematoma (blood accumulating under the skin)
- Infection (a slight risk any time the skin is broken)
Bringhurst FR, Demay MB, Kronenberg HM. Hormones and disorders of mineral metabolism. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology. 12th ed. Philadelphia, Pa: Elsevier Saunders; 2011:chap 28.
Marx SJ, Wells SA. Multiple endocrine neoplasia. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology. 12th ed. Philadelphia, Pa: Elsevier Saunders; 2011:chap 41.
Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.