Recombinant human thyrotropin before (131)I therapy in patients with nodular goitre: a meta-analysis of randomized controlled trials

Recombinant human thyrotropin (rhTSH)-aided radioiodine treatment for non-toxic multinodular goitre

BACKGROUND

Multinodular goitre is common in women. Treatments for non-toxic multinodular goitre include surgery, levothyroxine suppressive therapy, and radioiodine. Radioiodine therapy is the only non-surgical alternative for non-toxic multinodular goitre. However, a high amount of radioiodine is needed to enable the thyroid nodules to adequately take up the radioiodine, because the multinodular goitre takes up a low amount of iodine. Recombinant human thyrotropin (rhTSH) has been used to increase radioiodine uptake and reduce thyroid volume of the multinodular goitre. Whether the improved reduction of the goitre resulting from rhTSH-stimulated radioiodine therapy is beneficial to the person remains controversial.

OBJECTIVES

To assess the effects of recombinant human thyrotropin-aided radioiodine treatment for non-toxic multinodular goitre.

SEARCH METHODS

We searched the CENTRAL, MEDLINE, Scopus as well as ICTRP Search Portal and ClinicalTrials.gov. The date of the last search of all databases was 18 December 2020.

SELECTION CRITERIA

We included randomised controlled clinical trials (RCTs) comparing the effects of rhTSH-aided radioiodine treatment compared with radioiodine alone for non-toxic multinodular goitre, with at least 12 months of follow-up.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts for relevance. Screening for inclusion, data extraction, and risk of bias assessment were carried out by one review author and checked by a second. Our main outcomes were health-related quality of life (QoL), hypothyroidism, adverse events, thyroid volume, all-cause mortality, and costs. We used a random-effects model to perform meta-analyses, and calculated risk ratios (RRs) for dichotomous outcomes, and mean differences (MDs) for continuous outcomes, using 95% confidence intervals (CIs) for effect estimates. We evaluated the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included six RCTs. A total of 197 participants were allocated to rhTSh-aided radioiodine therapy, and 124 participants were allocated to radioiodine. A single dose of radioiodine was administered 24 hours after the intramuscular injection of a single dose of rhTSH. The duration of follow-up ranged between 12 and 36 months. Low-certainty evidence from one study, with 85 participants, showed uncertain effects for QoL for either intervention. RhTSH-aided radioiodine increased hypothyroidism compared with radioiodine alone (64/197 participants (32.5%) in the rhTSH-aided radioiodine group versus 15/124 participants (12.1%) in the radioiodine alone group; RR 2.53, 95% CI 1.52 to 4.20; 6 studies, 321 participants; moderate-certainty evidence in favour of radioiodine alone). A total of 118/197 participants (59.9%) in the rhTSH-aided radioiodine group compared with 60/124 participants (48.4%) in the radioiodine alone group experienced adverse events (random-effects RR 1.24, 95% CI 0.94 to 1.63; 6 studies, 321 participants; fixed-effect RR 1.23, 95% CI 1.02 to 1.49 in favour of radioiodine only; low-certainty evidence). RhTSH-aided radioiodine reduced thyroid volume with a MD of 11.9% (95% CI 4.4 to 19.4; 6 studies, 268 participants; moderate-certainty evidence). One study with 28 participants reported one death in the radioiodine alone group (very-low certainty evidence). No study reported on costs.

AUTHORS' CONCLUSIONS

RhTSH-aided radioiodine treatment for non-toxic multinodular goitre, compared to radioiodine alone, probably increased the risk of hypothyroidism but probably led to a greater reduction in thyroid volume. Data on QoL and costs were sparse or missing.

[Clinical practice guidelines "Management of iodine deficiency disorders"]

Iodine deficiency disorders is a sweeping term that includes structural and functional impairment of the thyroid gland.These clinical guidelines include algorithms for the diagnosis and treatment of euthyroid goiter and nodular/ multinodular goiter in adults and children. In addition, these clinical guidelines contain information on methods for an adequate epidemiological assessment of iodine deficiency disorders using such markers as the percentage of goiter in schoolchildren, the median urinary iodine concentration, the level of neonatal TSH, the median thyroglobulin in children and adults. As well from these clinical guidelines, you can get to know the main methods and groups of epidemiological studies of iodine deficiency disorders.

Fixed 30 mCi 131I-iodine therapy without recombinant human thyroid-stimulating hormone stimulation as an attractive therapeutic alternative in nontoxic nodular goiter

OBJECTIVE

To analyze outcomes of patients with compressive nontoxic multinodular goiter after 131I-iodine 30 mCi treatment without previous use of recombinant human thyroid-stimulating hormone or methimazole.

METHODS

We evaluated fixed-dose radioiodine therapy outcomes in patients with nontoxic multinodular goiter who did not accept thyroidectomy as a therapeutic option. Laboratory thyroid function and thyroid volume estimated by ultrasound were assessed before and one year after radioiodine therapy.

RESULTS

Twenty euthyroid female patients received 30 mCi of 131I-iodine without recombinant human thyroid-stimulating hormone or methimazole pretreatment. Median thyroid volume and Tc-99m sodium pertechnetate thyroid uptake before radioiodine therapy were 68.05 cm (31.3-295.3) and 0.5% (0.1%-1.2%), respectively. One year after radioiodine therapy, thyroid volume decreased to 55.4 cm (19.8-149.9), and merely 4 patients (20%) developed hypothyroidism. Thyroid volume decreased significantly after radioiodine therapy, presenting a variation of -21.1 cm (-161.3 to -0.8) and -30.61% (-73.88 to -1.02), both with P < 0.0001. Thyroid volume variation was positively correlated with thyroid uptake in Spearman's correlation (r = 0.4730; P = 0.0352). The group satisfied with radioiodine therapy (85%, n = 17) showed a significant reduction in thyroid volume, -25.8 cm (-161.3 to -6.2) and -36.74% (-73.88 to -9.95). The dissatisfied group (15%, n = 3) showed -1.0 cm (-2.0 to -0.8) and -1.67% (-3.38 to -1.02) in thyroid volume, P = 0.0081. Patients that complained about dysphagia presented a lower percentage of thyroid volume decrease after radioiodine therapy, -21.97% (-70.12 to -1.02, P = 0.0430).

CONCLUSIONS

A substantial reduction in thyroid volume associated with a low incidence of hypothyroidism and a high satisfaction rate support the use of conventional radioiodine therapy with a fixed dose of 30 mCi. This therapy is an attractive and cheaper therapeutic alternative in selected patients with nontoxic multinodular goiter.

[Radioiodine therapy for benign thyroid diseases (version 5). German Guideline]

The version 5 of the guideline for radioiodine therapy of benign thyroid disorders is an update of the version 4, which was published by the German Society of Nuclear Medicine (Deutsche Gesellschaft für Nuklearmedizin, DGN) in co-ordination with the German Society of Endocrinology (Deutsche Gesellschaft für Endokrinologie, DGE, Sektion Schilddrüse) and the German Society of General- and Visceral-Surgery (Deutsche Gesellschaft für Allgemein- und Viszeralchirurgie, DGAV) in 2007. This guideline was harmonized with the recommendations of the European Association of Nuclear Medicine (EANM). According to the German "Directive on Radiation Protection in Medicine" the physician specialised in nuclear medicine ("Fachkunde in der Therapie mit offenen radioaktiven Stoffen") is responsible for the justfication to treat with radioiodine. Therefore, relevant medical indications for radioiodine therapy and alternative therapeutic options are discussed within the guideline. This procedure guideline is developed in the consensus of a representative expert group. This fulfils the level S1 (first step) within the German classification of Clinical Practice Guidelines.

2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis

BACKGROUND

Thyrotoxicosis has multiple etiologies, manifestations, and potential therapies. Appropriate treatment requires an accurate diagnosis and is influenced by coexisting medical conditions and patient preference. This document describes evidence-based clinical guidelines for the management of thyrotoxicosis that would be useful to generalist and subspecialty physicians and others providing care for patients with this condition.

METHODS

The American Thyroid Association (ATA) previously cosponsored guidelines for the management of thyrotoxicosis that were published in 2011. Considerable new literature has been published since then, and the ATA felt updated evidence-based guidelines were needed. The association assembled a task force of expert clinicians who authored this report. They examined relevant literature using a systematic PubMed search supplemented with additional published materials. An evidence-based medicine approach that incorporated the knowledge and experience of the panel was used to update the 2011 text and recommendations. The strength of the recommendations and the quality of evidence supporting them were rated according to the approach recommended by the Grading of Recommendations, Assessment, Development, and Evaluation Group.

RESULTS

Clinical topics addressed include the initial evaluation and management of thyrotoxicosis; management of Graves' hyperthyroidism using radioactive iodine, antithyroid drugs, or surgery; management of toxic multinodular goiter or toxic adenoma using radioactive iodine or surgery; Graves' disease in children, adolescents, or pregnant patients; subclinical hyperthyroidism; hyperthyroidism in patients with Graves' orbitopathy; and management of other miscellaneous causes of thyrotoxicosis. New paradigms since publication of the 2011 guidelines are presented for the evaluation of the etiology of thyrotoxicosis, the management of Graves' hyperthyroidism with antithyroid drugs, the management of pregnant hyperthyroid patients, and the preparation of patients for thyroid surgery. The sections on less common causes of thyrotoxicosis have been expanded.

CONCLUSIONS

One hundred twenty-four evidence-based recommendations were developed to aid in the care of patients with thyrotoxicosis and to share what the task force believes is current, rational, and optimal medical practice.