Recombinant Human TSH Versus Thyroid Hormone Withdrawal: The Role in the Preparation for RAI Therapy in Differentiated Thyroid Cancer: A Comprehensive Evidence-Based Review.

Radioactive iodine (RAI) therapy plays a fundamental role in the management of differentiated thyroid cancer (DTC) following appropriate surgical intervention. High levels of TSH are required in order to achieve maximum RAI uptake in residual thyroid tissue or metastatic cells. The two techniques that are most commonly used are thyroid hormone withdrawal (THW), which induces endogenous TSH elevation by creating a hypothyroid state, and exogenous stimulation with recombinant human TSH (rhTSH). This review compares both approaches over a range of DTC risk categories. Extensive evidence demonstrates that rhTSH and THW yield equivalent oncological outcomes, including remnant ablation success, recurrence-free survival, and overall survival, in low-, intermediate-, and high-risk disease. Additionally, rhTSH maintains quality of life by avoiding hypothyroid symptoms. While THW continues to be an excellent option when there is a lack of availability of rhTSH, its disadvantages, particularly the transient hypothyroid state, must be carefully weighed against the demonstrated equivalence in efficacy. In current clinical practice, rhTSH is frequently the preferred option for its convenience, safety, and patient-centered benefits; however, the selection of the optimal approach should be based on individual clinical circumstances and patients' preferences, as well as resource considerations.