Thyroglobulin (Serum) with Qualitative or Confirmatory Immunoassay
This test measures the level of thyroglobulin, a protein produced by thyroid cells, often used to monitor thyroid function and cancer treatment.
["Thyroglobulin helps track thyroid health and cancer recurrence after treatment."]
Key facts at a glance
- LOINC
- 83117-2
- Short code
- Thyroglob IgG SerPl IA-aCnc
- Synonyms
- Thyroglob IgG SerPl IA-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- ia
- CPT
- 82784
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Doctors may order this test to check for thyroid cancer, monitor its treatment progress, or evaluate thyroid function in certain conditions. It’s commonly used after thyroid surgery or radioactive iodine treatment to ensure cancer hasn’t returned.
What to Expect Before the Test
No special preparation is needed, but you may be asked to fast for 8–12 hours before the test if instructed by your healthcare provider. Bring any medications or supplements you’re taking, as some may affect results.
How the Test Is Performed
A blood sample is drawn from a vein in your arm using a needle. The blood is sent to a lab for analysis using an immunoassay method to detect thyroglobulin levels.
Possible Results and Interpretation
Results may be qualitative (positive/negative) or quantitative (exact concentration). Low or undetectable levels may indicate thyroid cancer remission, while elevated levels could signal recurrence or other thyroid issues. Your doctor will interpret results in the context of your medical history.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Thyroglobulin is a tumor marker for thyroid cancer. After treatment, low or absent levels suggest cancer is likely gone, but further monitoring may still be needed. High levels may indicate persistent or recurrent cancer, thyroiditis, or other thyroid disorders. Always discuss results with your healthcare provider.
Short name
Thyroglobulin (Serum) Test
Frequently asked questions
What does a positive or negative result mean?
Can diet or medications affect thyroglobulin levels?
How often will I need this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
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Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy