Postoperative Radioactive Iodine (RAI) Treatment for Differentiated Thyroid Cancer

The references listed below are used in this DynaMed topic primarily to support background information and for guidance where evidence summaries are not felt to be necessary. Most references are incorporated within the text along with the evidence summaries.

1. Haugen BR, Alexander EK, Bible KC, et al. 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer. Thyroid. 2016 Jan;26(1):1-133full text, commentary can be found in Endocrine 2017 Aug;57(2):359.
2. Avram AM, Giovanella L, Greenspan B, et al. Society of Nuclear Medicine and Molecular Imaging (SNMMI) Procedure Standard/European Association of Nuclear Medicine (EANM) Practice Guideline for Nuclear Medicine Evaluation and Therapy of Differentiated Thyroid Cancer: Abbreviated Version. J Nucl Med. 2022 Jun;63(6):15N-35N.
3. Tuttle RM, Ahuja S, Avram AM, et al. Controversies, Consensus, and Collaboration in the Use of I¹³¹ Therapy in Differentiated Thyroid Cancer: A Joint Statement from the American Thyroid Association, the European Association of Nuclear Medicine, the Society of Nuclear Medicine and Molecular Imaging, and the European Thyroid Association. Thyroid. 2019 Apr;29(4):461-470.
4. Sparano C, Moog S, Hadoux J, et al. Strategies for Radioiodine Treatment: What's New. Sparano C, Moog S, Hadoux J, et al. Strategies for Radioiodine Treatment: What's New. Cancers (Basel) 2022 Aug 4;14(15).

• American Thyroid Association (ATA) grading system of recommendations:
  • Strength of recommendations:
    • Strong recommendation:
      • Can be offered to most patients in most applicable circumstances without reservation (with high- or moderate-quality evidence)
      • Can be offered to most patients in most applicable circumstances; may change when higher-quality evidence becomes available (with low-quality evidence)
    • Weak recommendation:
      • Best action may differ based on circumstances or patients’ values (with high- or moderate-quality evidence)
      • Alternative options may be equally reasonable (with low-quality evidence)
    • No recommendation:
      • Insufficient - insufficient evidence exists to recommend for or against
  • Levels of evidence:
    • For therapeutic interventions:
      • High - randomized controlled trial (RCT) without important limitations or overwhelming evidence from observational studies
      • Moderate - RCT with important limitations or strong evidence from observational studies
      • Low - observational studies/case studies
      • Insufficient - evidence is conflicting, of poor quality, or lacking
    • For diagnostic interventions:
      • High - evidence from ≥ 1 well-designed nonrandomized diagnostic accuracy studies or systematic reviews/meta-analyses of such observational studies with no concern about internal validity or external generalizability of the results
      • Moderate - evidence from nonrandomized diagnostic accuracy studies with ≥ 1 possible limitations causing minor concern about internal validity or external generalizability of the results
      • Low - evidence from nonrandomized diagnostic accuracy studies with ≥ 1 important limitations causing serious concern about internal validity or external generalizability of the results
      • Insufficient - evidence may be of such poor quality, conflicting, lacking, or not externally generalizable to the target clinical population such that the estimate of the true effect of the test is uncertain and does not permit a reasonable conclusion to be made
  • Reference - ATA guideline on management of adult patients with thyroid nodules and differentiated thyroid cancer (Thyroid 2016 Jan;26(1):1), commentary can be found in Thyroid 2016 Feb;26(2):319
• European Thyroid Association (ETA) grading system of recommendations:
  • Strength of recommendation:
    • Strong ("we recommend") - clinically important best practice; applicable to most patients in most circumstances
    • Weak ("we suggest") - clinician should consider; applicable only to certain patients or under certain circumstances
  • Quality of evidence:
    • Level 1 - High-quality evidence - RCT evidence/meta-analysis
    • Level 2 - Moderate-quality evidence - intervention short of RCT or large observational studies
    • Level 3 - Low quality - case-control studies, case series
    • Level 4 - Very-low quality - case reports, expert opinion
  • Reference - ETA guideline on management of pediatric thyroid nodules and differentiated thyroid carcinoma (Eur Thyroid J 2022 Dec 1;11(6):doi:10.1530/ETJ-22-0146)
• European Thyroid Association (ETA) grading:
  • Consensus recommendation - predominantly based on the evidence of retrospective studies, where biases cannot be excluded, in particular in patient selection
  • Reference - ETA consensus statement on indications for postsurgical radioiodine therapy in differentiated thyroid cancer (Eur Thyroid J 2022 Jan 1;11(1):doi:10.1530/ETJ-21-0046)

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