Recombinant human thyroid-stimulating hormone is effective for radioiodine ablation of post-surgical thyroid remnants

Abstract

Our data confirm that, when the interference of iodine is minimized, rhTSH is highly effective for the treatment of post-surgical thyroid remnants using a low dose of (131)I.

Preparation with Recombinant Humanized Thyroid-Stimulating Hormone before Radioiodine Ablation after Thyroidectomy: A Systematic Review

“…In all four studies of therapeutic use 15,[17][18][19] , 0.9 mg of rhtsh was administered intramuscularly on 2 consecutive days, followed by ra either 24 15,17,19 or 48 18 hours after the second dose of rhtsh. Patients in all four studies had previously undergone total or near-total thyroidectomy.…”

“…The cohort studies by Barbaro et al 17 and Pacini et al 18 and the retrospective review by Robbins et al 19 are limited by lack of randomization, making it unclear whether selection bias (either self-selection by patients or selection by physicians) affected the results of a given study. In addition, Barbaro et al 17 used a historical control group (that is, a thyroid hormone withdrawal group), which is methodologically problematic.…”

ALARA in rhTSH-stimulated post-surgical thyroid remnant ablation: what is the lowest reasonably achievable activity?

“…For the studies using 1.11 GBq (30 mCi) 131 I, the results are more differentiated: whereas the studies by Barbaro et al [6,7] did not show a significant difference in the rates of successful ablation between patients prepared with rhTSH and LT 4 withdrawal, Pacini et al [5] did find a considerable difference. Some speculation is possible about the reason for the difference found by Pacini et al; the most likely explanation is that the administration of the ablative 131 I activity on the second day after the last administration of rhTSH is too late.…”

“…Its effectiveness in patient preparation before 131 I ablation has been shown in multiple prospective studies [1][2][3][4][5][6][7].…”

“…Consequently it is conceivable that the lower the ablative 131 I activity used, the more important the reduction of stable iodine becomes. The studies by Barbaro et al [6,7], who performed ablation under rhTSH stimulation with an activity of only 1.1 GBq after patient preparation with a stringent diet as well as a socalled mini-withdrawal (i.e. the discontinuation of LT 4 for 4 days before 131 I administration as it is a source of stable iodine), seem to prove that it is possible to effectively ablate patients using only 1.11 GBq when paying attention to the reduction of the whole-body iodine pool; the ablation success rates in the studies by Barbaro et al were comparable with those in studies which used a higher ablative 131 I activity.…”