Update on Free T3 Testing

There are a few circumstances that may affect Free T3 (triiodothyronine) test results.  The following two test descriptions from LabCorp, a major nationwide diagnostic laboratory, indicate conditions which may interfere with testing and when the Dialysis and LC/MS-MS may be preferred.  Biotin may interfere with Free T3 and other thyroid tests.  Thyroid antibodies may interfere… Continue reading Update on Free T3 Testing

Tg Antibodies Rising

This is information I compiled related to questions concerning Thyroglobulin Antibodies (TgAb)remaining elevated or increasing following total thyroidectomy despite having low or undetectableThyroglobulin (Tg) and whether TgAb can be used to detect recurrence of thyroid cancer. Elevated Thyroglobulin Antibodies (TgAb) in the absence of elevated Tg levels Thyroglobulin is uniquely produced by thyroid follicular cells.Biotin… Continue reading Tg Antibodies Rising

Thyroid Cancer Test and ICD Codes

Test and ICD Codes - Current as of 15 December, 2021These test and ICD codes can be helpful if your tests are being ordered by a primary care provider or an endocrinologist who does not specialize with thryoid cancer patients. Lab Corphttps://www.labcorp.com/test-menu/search Order CodeOrder Code NameResult CodeResult Code NameUnits224576TSH+Free T44264 19745TSH T4,Free(Direct)uIU/mL ng/dL10389Triiodothyronine (T3), Free10389Triiodothyronine… Continue reading Thyroid Cancer Test and ICD Codes

Falsely Elevated Thyroglobulin – HAMA

Serum Thyroglobulin (Tg) is the primary tumor marker measured postoperatively to monitor for recurrence of thyroid cancer.  Tg concentrations reflect the mass, or amount, of residual thyroid tissue — remnant or tumor. An unexpected elevated Tg result which is not consistent with clinical findings and history is distressing for the patient and can lead to… Continue reading Falsely Elevated Thyroglobulin – HAMA