What is this test?
Calcitonin is a hormone made by certain cells of the thyroid gland. It is mainly used in the evaluation and follow-up of medullary thyroid carcinoma in the appropriate clinical context.
Why might it be ordered?
- In the case of a thyroid nodule or family risk, when the specialist considers that the examination is appropriate.
- For follow-up after treatment of medullary thyroid carcinoma.
What sample is needed?
A healthcare professional collects a venous blood sample. Depending on the method, the laboratory uses serum or plasma.
How should you prepare?
Tell the laboratory about all medicines, hormone treatments, vitamins and supplements you take. Do not stop or change treatment unless your clinician tells you to. Follow any instructions about fasting and the time of collection.
How should you understand the result?
A high result does not by itself prove cancer and may have other causes. The trend, test method and any follow-up investigations all matter. Your result is interpreted using the reference interval on the laboratory report and in the context of your symptoms, medical history and other test findings.
Sources and editorial status
This patient-facing text is an editorial draft. It should be approved by a laboratory physician before official publication.