Controversies about Radioactive Iodine-131 Remnant Ablation in Low Risk Thyroid Cancers: Are We Near A Consensus?

  • Zaman, Maseeh Uz (Department of Radiology, The Aga Khan University Hospital) ;
  • Fatima, Nosheen (Department of Nuclear Medicine, Ziauddin Medical University) ;
  • Padhy, Ajit Kumar (Department of Nuclear Medicine, Singapore General Hospital) ;
  • Zaman, Unaiza (2nd Year MBBS, Dow University of Health Sciences)
  • Published : 2013.11.30


Well differentiated thyroid cancers (WDTC), including papillary (80%) and follicular (10%) types, are the most common endocrine cancers globally. Over the last few decades most the diagnosed cases have fallen into low risk categories. Radioactive iodine-131 (RAI) has an established role in reducing recurrence and improving the survival in high risk patients. In patients with primary tumor size <1 cm, RAI is not recommended by many thyroid societies. However, low risk WDTC has been an arena of major controversies, most importantly the role and dose of adjuvant RAI for remnant ablation to minimize chances of recurrence and improving survival. This review is an attempt to update readers about the previous and existing practice based on results of non-randomized trials and evolving trends fueled by recently published randomized studies.


Papillary thyroid cancer;follicular thyroid cancer;low dose iodine;remnant ablation


  1. Bal CS, Kumar A, Pant GS (2004). Radioiodine dose for remnant ablation in differentiated thyroid carcinoma: a randomized clinical trial in 509 patients. J Clin Endocrinol Metab, 89, 1666-73.
  2. Bal CS, Padhy AK, Jana S, et al (1996). Prospective randomized clinical trial to evaluate the optimal dose of 131I for remnant ablation in patients with differentiated thyroid carcinoma. Cancer, 77, 2574-80.<2574::AID-CNCR22>3.0.CO;2-O
  3. Benua RS, Cicle NR, Sonenberg et al (1962). The relation of radioiodine dosimetry to results and complications in the treatment of metastatic thyroid cancer. Am J Roentgenol, 87, 171-82.
  4. Brierley J, Tsang R, Panzarella T, et al (2005). Prognostic factors and the effect of treatment with radioactive iodine and external beam radiation on patients with differentiated thyroid cancer seen at a single institution over 40 years. Clin Endocrinol, 63, 418-27.
  5. Caglara M, Bozkurta FM, Akcaa CK, et al (2012). Comparison of 800 and 3700MBq iodine-131 for the postoperative ablation of thyroid remnant in patients with low-risk differentiated thyroid cancer. Nuclear Med Communications, 33 268-74.
  6. Carballo M, Quiros RM (2012). To treat or not to treat: the role of adjuvant radioiodine therapy in thyroid cancer patients. J Oncol, 2012, 707156.
  7. Cheng W, Ma C, Fu H, et al (2013). Low- or high-dose radioiodine remnant ablation for differentiated thyroid carcinoma: a meta-analysis. J Clin Endocrinol Metab, 98, 1353-60.
  8. Cooper DS, Doherty GM, Haugen BR (2009). Revised American thyroid association management guidelines for patients with thyroid nodules and differentiated thyroid cancer. Thyroid, 19, 1167-214.
  9. Davies L, Welch HG (2002). Increasing incidence of thyroid cancer in the United States, 1973-2002. JAMA, 295, 2164-67.
  10. Doi SAR, Woodhouse NJ (2000). Ablation of the thyroid remnant and 131I dose in differentiated thyroid cancer. Clin Endocrinol, 52, 763-73.
  11. Doi SAR, Woodhouse NJ, Thalib L, et al (2007). Ablation of the thyroid remnant and I-131 dose in differentiated thyroid cancer: a meta-analysis revisited. Clinical Med & Res, 5, 87-90.
  12. Edwards BK, Howe HL, Ries LA, et al (2002). Annual report to the nation on the status of cancer, 1973-1999, featuring implications of age and aging on US cancer burden. Cancer, 94, 2766-92.
  13. Elisei R, Molinaro E, Agate L, et al (2010). Are the clinical and pathological features of differentiated thyroid carcinoma really changed over the last 35 years? Study on 4187 patients from a single Italian institution to answer this question. J Clin Endocrinol Metab, 95, 1516-27.
  14. Grebe SKG, Hay ID (1997). Follicular cell-derived thyroid carcinomas. In: Arnold A, ed, Endocrine neoplasms. Kluwer Academic Publishers, 91-140.
  15. Hackshaw A, Harmer C, Mallick U, et al (2007). 131I activity for remnant ablation in patients with differentiated thyroid cancer: a systematic review. J Clin Endocrinol Metab, 92, 28-38.
  16. Hay ID, Thompson GB, Grant CS, et al (2002). Papillary thyroid carcinoma managed at the Mayo Clinic during six decades (1940-1999): temporal trends in initial therapy and long-term outcome in 2444 consecutively treated patients. World J Surg, 26, 879-85.
  17. Haymart MR, Banerjee M, Stewart AK, et al (2011). Use of radioactive iodine for thyroid cancer. JAMA, 306, 721-28.
  18. Iyer NG, Morris LG, Tuttle RM, et al (2011). Rising incidence of second cancers in patients with low-risk (T1N0) thyroid cancer who receive radioactive iodine therapy. Cancer, 117, 4439-46.
  19. Jonklaas J, Cooper DS, Ain BK, et al (2010). Radioiodine therapy in patients with stage 1 differentiated thyroid cancer. Thyroid, 20, 1423-6.
  20. Leung SF, Law MW, Ho SK (1992). Efficacy of low-dose iodine-131 ablation of post-operative thyroid remnants: a study of 69 cases. Bri J Radiol, 65, 905-9.
  21. Maenpaa HO, Heikkonen J, Vaalavirta L, et al (2008). Low vs. high radioiodine activity to ablate the thyroid after thyroidectomy for cancer: a randomized study. PLoS ONE, 3, 1885
  22. Mallick U, Harmer C, Hackshaw A, et al (2012). Iodine or not (IoN) for low-risk differentiated thyroid cancer; the next UK national cancer research network randomized trial following HiLo. Clin Oncol, 24, 159-61.
  23. Mallick U, Harmer C, Yap B, et al (2012). Ablation with low-dose radioiodine and thyrotropin alfa in thyroid cancer. N Engl J Med, 366, 1674-85.
  24. Maxon HR, Thomas SR, Hertzberg VS, et al (1983). Relation between effective radiation dose and outcome of radioiodine therapy for thyroid cancer. N Engl J Med, 309, 937-41.
  25. Mazzaferri EL, Kloos RT (2001). Current approaches to primary therapy for papillary and follicular thyroid cancer. J Clin Endocrinol Metab, 96, 1447-63.
  26. Mazzaferri EL, Young RL (1981). Papillary thyroid carcinoma: a 10 year follow-up report of the impact of therapy in 576 patients. Am J Med, 70, 511-8.
  27. Pacini F, Cetani F, Miccoli P, et al (1994). Outcome of 309 patients with metastatic differentiated thyroid carcinoma treated with radioiodine. World J Surg, 18, 600-4.
  28. Robbins RJ, Schlumberger MJ (2005). The evolving role of 131I for the treatment of differentiated thyroid carcinoma. J Nucl Med, 46, 28-37.
  29. Rubino C, de Vathaire F, Dottorini ME, et al (2003). Second primary malignancies in thyroid cancer patients. Br J Cancer, 89, 1638-44.
  30. Sandeep TC, Strachan MW, Reynolds RM, et al (2006). Second primary cancers in thyroid cancer patients: a multinational record linkage study. J Clin Endocrinol Metab, 91, 1819-25.
  31. Sawka AM, Thephamongkhol K, Brouwers M, et al (2004). Clinical review 170: A systematic review and metaanalysis of the effectiveness of radioactive iodine remnant ablation for well-differentiated thyroid cancer. J Clin Endocrinol Metab, 89, 3668-76.
  32. Schlumberger M, Catargi B, Borget I, et al (2012). Strategies of radioiodine ablation in patients with low-risk thyroid cancer. N Engl J Med, 366, 1663-73.
  33. Schvartz C, Bonnetain F, Dabakuyo, et al (2012). Impact on overall survival of radioactive iodine in low-risk differentiated thyroid cancer patients. J Clin Endocrinol Metab, 97, 1526-35.
  34. Seidlin S, Oshry E, Yallow AA (1948). Spontaneous and experimentally induced uptake of radioactive iodine in metastases from thyroid carcinoma. J Clin Endocrinol Metab, 8, 423-25.
  35. Shen DH, Kloos RT, Mazzaferri EL, Jhian SM (2001). Sodium iodide symporter in health and disease. Thyroid, 11, 415-25.
  36. Simpson WJ, Panzarella T, Carruthers JS, et al (1998). Papillary and follicular thyroid cancer: impact of treatment in 1578 patients. Int J Radiat Oncol Biol Phys, 14, 1063-75.
  37. Solomon BL, Wartofsky L, Burman KD (1996). Current trends in the management of well differentiated papillary thyroid carcinoma. J Clin Endocrinol Metab, 81, 333-9.
  38. Vaisman F, Shaha A, Fish S, et al (2001). Initial therapy with either thyroid lobectomy or total thyroidectomy without radioactive iodine remnant ablation is associated with very low rates of structural disease recurrence in properly selected patients with differentiated thyroid cancer. Clinical Endocrinology, 75, 112-9.
  39. Wartofsky L, Sherman SI, Gopal J, et al (1998). Therapeutic controversy: the use of radioactive iodine in patients with papillary and follicular thyroid cancer. J Clin Endocrinol Metab, 83, 4195-203.
  40. Yamashita H, Noguchi S, Murakami N, et al (1997). Extracapsular invasion of lymph node metastasis is an indicator of distant metastasis and poor prognosis in patients with thyroid papillary carcinoma. Cancer, 80, 2268-72.<2268::AID-CNCR8>3.0.CO;2-Q

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