Thyroid Testing Services

LabCorp and Endocrine Sciences’ expertise in thyroid testing provides clinicians with a comprehensive portfolio for their thyroid needs. Some of the test options available at Endocrine Sciences to assist with your thyroid disorder diagnosis include:

  • Free thyroxine (T4) and free triiodothyronine (T3) assays by dialysis and HPLC/MS-MS, which provides enhanced accuracy over commonly used analog (automated) methods. Dialysis and HPLC/MS-MS may be preferred for evaluating patients who have conditions that impact protein binding capacity, including those who:
    • Have congenital absence of thyroxine-binding globulin (TBG).
    • Are pregnant.
    • Are taking oral contraceptives or undergoing hormone therapy.
    • Are taking antipsychotic medications.
    • Have been diagnosed with a malignancy or other critical illness.
  • Molecular blood testing for RET gene mutations
    • Testing includes mutation analysis by sequencing of exons 10, 11, 13, 14, 15, and 16 of the RET proto-oncogene.
    • Mutations found in these exons have been associated with patients that develop multiple endocrine neoplasia type 2 (MEN 2) and/or familial medullary thyroid carcinoma (FMTC). Testing for RET germline mutations is recommended in patients with a family or personal history consistent with MEN 2 or FMTC.
    • Known mutation testing of RET mutations is also available for patients with family members who have previously identified mutations.
  • Comprehensive thyroglobulin profile, which offers enhanced sensitivity for thyroglobulin and antithyroglobulin testing to monitor for thyroid cancer recurrence. This profile offers a dual assay strategy for Tg in an effort to minimize the potential effect of TgAb interference.
    • Specimens are tested for TgAb using a sensitive IMA.
    • Specimens with TgAb below the detectable limit (<1.0 IU/mL) are tested for Tg by sensitive second-generation IMA.
    • Specimens with any measurable TgAb levels (≥ 1.0 IU/mL) are tested for Tg by radioimmunoassay (RIA), which is less prone to interference by TgAb.
    • Includes extended (1 year) specimen storage
  • Thyroglobulin testing for lymph node aspirate diluted in saline.
    • Aspirate material from lymph nodes can be tested for the presence of thyroglobulin if there is suspicion that thyroid cancer has spread to the lymphatic system.
    • The lymph node aspirate is collected and washed into a 1 mL saline solution, and the saline solution is tested for the presence of thyroglobulin.
    • A convenient lymph node aspirate collection kit is available that includes instructions and a vial containing 1 mL of saline solution.