Dear Ask The Doctor: My 16 year old daughter's blood test came back with an elevated level of Thyroglobulins (it was 52 and they doctor said it should be 30). Is this a concern at all for thyroid cancer?
Dear Patient: Thyroglobulin is a protein produced and used by the thyroid gland to make the thyroid hormones thyroxine (T4) and triiodothyronine (T3). An isolated elevated thyroglobulin level is of limited significance, if all thyroid function tests are within the normal range, and your daughter is asymptomatic. Thyroglobulin levels in the blood can be elevated in cases of Graves' disease, an autoimmune thyroid disease. They can also be used as a tumor marker for certain kinds of thyroid cancer, and to monitor response to treatment. Patients with Hashimoto's thyroiditis or Graves' disease may develop antibodies against Thyroglobulin, known as anti-thyroglobulin antibodies. Some patients who are healthy also test positive for one or more thyroid antibodies and these findings tend to be higher in women and increased age. I would discuss the elevated thyroglobulin level result with your daughter’s family physician. This result must be interpreted in the correct clinical context, with the presence of relevant symptoms and abnormal thyroid function testing.