At his appointment with his new endocrinologist, he reviewed his long history of papillary thyroid cancer, which was diagnosed about 20 years ago. He had a total thyroidectomy, which was followed by radioactive iodine ablation therapy. The original pathology report indicated that the nodule was 1.5 cm in its greatest dimension, confined to the right lobe of the thyroid. His post-treatment nuclear medicine scan was reported as normal. After his initial diagnosis was made, his endocrinologist explained the importance of keeping his TSH level suppressed on levothyroxine and having his blood work checked at least once or twice a year. For several years he followed up with his endocrinologist, who ordered several nuclear medicine body scans which were reported as normal. His thyroglobulin level, off suppressive therapy, was undetectable. An ultrasound of his neck was also reported as normal. Ten years ago his endocrinologist died, and he has been followed by his primary care provider since then. On one occasion his doctor was going to reduce his levothyroxine dose but decided not to do so because of concerns expressed to him by the patient.
Current guidelines for thyroid cancer emphasize the importance of categorizing the cancer into one of three groups based on the likelihood of a recurrence or metastasis (4). Consideration should be made based on the patient’s age and co-morbid conditions such as risks for coronary artery disease. Patients at a high risk for recurrences as demonstrated in retrospective studies have improved outcomes when their TSH levels are suppressed below 0.1 mU/L (4). This has not been shown to be the case for low risk patients (4-6). A summary of these groups and treatment recommendations follows:
- If the patient has persistent disease, the serum TSH should be maintained below 0.1 mU/L as long as it can be safely administered.
- If the patient is free of disease, but at high risk for recurrence or metastasis, the TSH should be kept between 0.1 and 0.5 mU/L for five to 10 years.
- Those at low risk and free of disease may be titrated to TSH levels in the low normal range between 0.3 to 2 mU/L.
- Treatment of differentiated thyroid cancer has changed significantly over time.
- It is often prudent to consult experts in their respective clinical specialties to re-evaluate clinical problems which appear to be long-standing or even stable.
- Patients should be given up-to-date information regarding their disease state, treatment options and follow-up plan, reinforcing the importance of timely re-evaluations.
- Not all differentiated thyroid cancers are alike and treatment, based on staging and risks for recurrences or metastasis, varies significantly.
- Co-morbid conditions and disease-free intervals must be considered when determining the aggressiveness of the treatment plan.
- Bates D, Clark NG, Cook RI, Hellman R, et al. American College of Endocrinology and American Association of Clinical Endocrinologists position statement on patient safety and medical system errors in diabetes and endocrinology. EndocrPract. 2005;11:197-202. [go to PubMed]
- Bates DW, Gawande AA. Improving safety with information technology. N Engl J Med. 2003;348:2526-2534. [go to PubMed]
- Consequences of mild thyrotoxicosis and atrial fibrillation.Sawin CT, et al. N Engl J Med. 1994;331:1249-1252
- Management Guidelines for Patients with Thyroid Nodules and Differentiated Thyroid Cancer The American Thyroid Association Guidelines Taskforce* Members: David S. Cooper,(Chair), Gerard M. Doherty,Bryan R. Haugen,Richard T. Kloos, Stephanie L. Lee,Susan J. Mandel,Ernest L. Mazzaferri,BryanMcIver,Steven I. Sherman, and R. Michael Tuttle.
- Cooper DS, Specker B, Ho M, Sperling M, Ladenson PW, Ross DS, Ain KB, Bigos ST, Brierly JD, Hangen BR, Klein I, Robbins J, Sherman SI, Taylor T, Maxon HR 3rd 1998 Thy- rotropin suppression and disease progression in patients with differentiated thyroid cancer: Results from the National Thyroid Cancer Treatment Cooperative Registry.
- Pujol P, Daures JP, Nsakala N, Baldet L, Bringer J, Jaffiol C1996 Degree of thyrotropin suppression as a prognostic determinant in differentiated thyroid cancer. J Clin Endocrinol Metab 81:4318–4323.