Thyroglobulin is a tumor marker widely used to evaluate the development of thyroid cancer, especially during its treatment, helping the doctor adapt the form of treatment and/or dosage, depending on the results.
Although not all types of thyroid cancer cause thyroglobulin, the most common types do, so levels of this marker usually increase in the blood in the presence of cancer.If the value of thyroglobulin continues to increase over time, this means that the treatment does not have the desired effect and needs to be modified.
- In rarer cases.
- The thyroglobulin test can also be used to determine the cause of hyperthyroidism or hypothyroidism.
- For example.
The thyroglobulin test is usually done before starting any treatment for thyroid cancer, so there is a reference value to compare and then repeated several times in time to assess whether the chosen form of treatment resulted in the cure of the cancer.
If you have chosen to have surgery to remove your thyroid, this test is also done frequently after surgery to make sure there are no cancer cells left at the site, which may re-develop.
In addition, in some cases of suspected hyperthyroidism, your doctor may also order a thyroglobulin test to identify diseases such as thyroiditis or Graves’ disease, for example.
See what tests evaluate your thyroid and when
The value of thyroglobulin in a healthy person, without thyroid alterations, is usually less than 10 ng / mL but can reach up to 40 ng / mL, so if the test result is greater than these values may indicate the presence of a thyroid problem.
Although the test result should always be interpreted by the doctor who prescribed it, the results usually mean:
If a type of cancer treatment has already been performed, if thyroglobulin is high, it may mean that the treatment has had no effect or that the cancer is developing again.
Although thyroglobulin increases in cancer cases, this test is not intended to confirm the presence of cancer.If suspected, a biopsy is still required to confirm the cancer.Learn about the main symptoms of thyroid cancer and how to confirm the diagnosis.
As this test is done in people who already have a thyroid disorder, when the value drops, it means that the cause is treated and that is why the gland produces less thyroglobulin.
However, if there is no suspicion of thyroid problems and the value is very low, this may also indicate a case of hypothyroidism, although rarer.
The test is done in a very simple way, just take a small blood sample from your arm.
In most cases, no preparation is required, but depending on the technique used to perform the test, some labs may recommend that you stop taking certain vitamin B7 supplements for at least 12 hours before the test.