title: Recombinant human thyroid-stimulating hormone-aided remnant ablation achieves a response to treatment comparable to that with thyroid hormone withdrawal in patients with clinically relevant lymph node metastases.
abstract: It has already been shown that remnant ablation in patients with thyroid cancer and lymph node (LN) metastases has similar results when patients are prepared after recombinant human thyroid-stimulating hormone (rhTSH) therapy or thyroid hormone withdrawal (THW). Due to the current changes in the risk-of-recurrence classifications, we decided to evaluate the initial response to treatment and the outcome at medium-term follow-up in 40 consecutive patients with clinically relevant lymph nodes who received radioiodine remnant ablation after rhTSH therapy (n = 20) or THW (n = 20). Each patient received either 100 or 150 mCi 131-I for ablation based on TNM status, and the mean amounts of 131-I used in the 2 groups were not significantly different. An excellent response to treatment was observed in 45% of the patients prepared after rhTSH therapy compared to 20% of those prepared after THW (p = 0.08). Three patients (2 in the THW group and 1 in the rhTSH group) who had N1a in the initial surgery presented with structural persistence as an initial response to treatment. One patient in the THW group had a follow-up of the persistent disease with no surgical treatment, and 2 others received a lateral LN dissection. When the status at final follow-up was considered (median follow-up 3.3 years, range 3-4.2), 60% of the patients ablated after rhTSH therapy were considered with no evidence of disease, compared to 30% of those who underwent THW. The frequency of structural persistence (metastatic LN) was similar in the 2 groups (15 vs. 25%), and the distribution of the responses at final follow-up was not statistically significantly different (p = 0.12). We conclude that preparation after rhTSH therapy seems to be as effective as after THW for patients with clinically relevant LN metastases.
authors.affiliation: Division of Endocrinology, Hospital de Clínicas, University of Buenos Aires, Buenos Aires, Argentina.
authors.forename: Fabián
authors.initials: F
authors.lastname: Pitoia
authors.affiliation: Division of Endocrinology, Hospital de Clínicas, University of Buenos Aires, Buenos Aires, Argentina.
authors.forename: Erika
authors.initials: E
authors.lastname: Abelleira
authors.affiliation: Division of Endocrinology, Hospital de Clínicas, University of Buenos Aires, Buenos Aires, Argentina.
authors.forename: Graciela
authors.initials: G
authors.lastname: Cross
keywords: Lymph node metastases; Recombinant human thyroid-stimulating hormone; Remnant ablation; Thyroid cancer; Thyroid hormone withdrawal