The optimal TSH level necessary for successful radioiodine ablation of differentiated thyroid carcinoma, as well as the time to reach this level, is a work in progress

  • Ismaheel O. Lawal
  • Mariza Vorster
  • Alfred O. Ankrah
  • Mike M. Sathekge
Letter to the Editor

Dear Editor,

We read with great interest the article by Piccardo et al. titled “Could short thyroid hormone withdrawal be an effective strategy for radioiodine remnant ablation in differentiated thyroid cancer patients?” [1]. The authors retrospectively reviewed the data of two groups of patients who had radioactive iodine (RAI) ablation post-total thyroidectomy for differentiated thyroid cancer. Group A (n = 85) patients had thyroid hormone withdrawal (THW) for 2 weeks, while group B patients (n= 137) had THW for 3–4 weeks. All patients in the two groups had sufficiently elevated thyroid-stimulating hormone (TSH) levels at the time of RAI ablation. The authors found no statistical significant difference between the groups regarding their age, gender, histological variant of thyroid carcinoma, tumor size, nodal status, or tumor aggressiveness. The serum TSH level at the time of ablation was significantly higher in group B patients compared with group A. This, however, did not have a...


Compliance with ethical standards

Conflict of interest

The authors declare that they have no financial or non-financial competing interests.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. This article does not contain any studies with animals performed by any of the authors.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Nuclear MedicineUniversity of Pretoria and Steve Biko Academic HospitalPretoriaSouth Africa
  2. 2.Department of Nuclear Medicine and Molecular ImagingUniversity Medical Center Groningen, University of GroningenGroningenThe Netherlands

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