ABBREVIATIONS & DEFINITIONS
Differentiated thyroid cancer: includes papillary (the most common) and follicular thyroid cancer.
Radioactive iodine (RAI): this plays a valuable role in diagnosing and treating thyroid problems since it is taken up only by the thyroid gland. I-131 is the destructive form used to destroy thyroid tissue in the treatment of thyroid cancer. I-123 is the nondestructive form that does not damage the thyroid and is used in scans to take pictures of the whole body to look for thyroid cancer (Whole Body Scan).
Total thyroidectomy: surgery to remove the entire thyroid gland.
Thyroid hormone therapy: patients with hypothyroidism are most often treated with Levothyroxine in order to return their thyroid hormone levels to normal. Replacement therapy means the goal is a TSH in the normal range and is the usual therapy. Suppressive therapy means that the goal is a TSH below the normal range and is used in thyroid cancer patients to prevent growth of any remaining cancer cells.
Thyroid hormone withdrawal: this is used to produce high levels of TSH in patients by stopping thyroid hormone pills and causing short-term hypothyroidism. This is mainly used in thyroid cancer patients before treating with radioactive iodine or performing a whole body scan.
Lymph node: bean-shaped organ that plays a role in removing what the body considers harmful, such as infections and cancer cells.
Neck lymph node dissection: systematic removal of an entire group of lymph nodes from the neck to treat lymph node metastasis.
Thyroglobulin: a protein made only by thyroid cells, both normal and cancerous. When all normal thyroid tissue is destroyed after radioactive iodine therapy in patients with thyroid cancer, thyroglobulin can be used as a thyroid cancer marker.
Stimulated thyroglobulin testing: this test is used to measure whether there is any cancer present in a patient that has previously been treated with surgery and radioactive iodine. TSH levels are increased, either by withdrawing the patient from thyroid hormone or treating the patient with recombinant human TSH (Thyrogen), then levels of thyroglobulin are measured. Sometimes this test is combined with a whole body iodine scan.
Diagnostic whole body scans: these radioactive iodine scans are performed under TSH stimulation, either after thyroid hormone withdrawal or after injections of recombinant human TSH, and usually include measuring serum thyroglobulin levels.