Time to reconsider nonsurgical therapy of benign non-toxic multinodular goitre: focus on recombinant human TSH augmented radioiodine therapy

Long-Term Effects of 0.1 mg Recombinant-Human-Thyrotropin-Stimulated Fixed-Dose Radioiodine Therapy in Patients with Recurrent Multinodular Goiter after Surgery

(1) Background: After thyroid malignancy is ruled out, treatment options for multinodular goiter patients include surgery, levothyroxine suppressive therapy, and 131-I therapy. Surgery effectively reduces goiter size but carries risks of surgical and anesthetic complications. 131-I therapy is the only nonsurgical alternative, but its effectiveness diminishes with goiter size and depends on iodine sufficiency. This study aimed to assess the efficacy and safety of 0.1 mg rhTSH as an adjuvant to a fixed dose of 131-I therapy in patients with a recurrence of large multinodular goiter, several years after the initial thyroidectomy. (2) Methods: 14 patients (13 females and 1 male), aged 59.14 ± 15.44 (range, 35-78 years) received 11mciu of 131-I, 24 h after the administration of 0.1 mg rhTSH. The primary endpoint was the change in thyroid volume (by ultrasound measurements) as well as in the diameter of the predominant nodule during a follow-up period of 10 years. Secondary endpoints were the alterations in thyroid function and potential adverse effects. (3) Results: A significant decrease in the volume of initial thyroid remnants (32.16 ± 16.66 mL) was observed from the first reevaluation (at 4 months, 23.12 ± 11.59 mL) as well as at the end of the follow-up period (10 years, 12.62 ± 8.76 mL), p < 0.01. A significant reduction in the dominant nodule was also observed (from 31.71 ± 10.46 mm in the beginning to 26.67 ± 11.05 mm). (4) Conclusions: Further investigation is needed since this approach could be attractive in terms of minimizing the potential risks of reoperation in these patients.

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.

Effect of thyroidectomy in patients with tracheal compression

OBJECTIVE

Various therapeutic methods are employed to reduce thyroid gland compression of the trachea. Differences in the amount of shrinkage in the thyroid gland, in the amount of amelioration of tracheal compression, and in the amount of fibrosis after treatment may occur with these different methods. Although the compression of the trachea decreases after thyroidectomy, the number of studies showing the extent of this is limited. The purpose of this study was to investigate the effect of thyroidectomy performed due to tracheal compression, to reveal the extent of improvement using magnetic resonance imaging (MRI), and to evaluate our results.

METHODS

In total, 30 patients, i.e., 24 women and 6 men, with tracheal compression secondary to thyroid gland enlargement and undergoing total thyroidectomy were included in this study. MRI performed before surgery and 6 months after surgery. The amount of deviation from the tracheal midline and the tracheal lateral and anteroposterior (AP) diameters were measured, compared, and subjected to statistical analysis.

RESULTS

Statistical analysis revealed significant differences between pre- and postoperative tracheal deviations, and lateral and AP diameters (p<0.001, p<0.001, and p=0.006, respectively). Histopathologically, benign or malignant pathology caused no significant difference in the postoperative improvement of tracheal anatomy (p=0.348 and p=0.148, respectively).

CONCLUSIONS

Thyroidectomy performed due to tracheal compression provides significant improvement in tracheal anatomy. Due to its rapid and effective results, thyroidectomy should be one of the first options considered in the treatment of thyroid diseases with compression findings.

Alteration of Trace Elements in Multinodular Goiter, Thyroid Adenoma, and Thyroid Cancer

Modest progress has been made in understanding the role of trace elements as endocrine disruptors. The aim of this study was to examine whether there is a change in the content of trace elements in thyroid disease, as well as whether the ratio of elements could be considered a blood marker for thyroid disease. In addition, this study examined the influence of biological and clinical/pathological parameters on the elemental profile. Blood samples from patients diagnosed with multinodular goiter (MNG), thyroid adenoma (TA), and thyroid cancer (TC) were examined and compared with control samples using chemometric analysis. The concentrations of essential (Mn, Co, Cu, Zn, Se) and toxic elements (Ni, As, Cd, Pb, U) were determined by ICP-MS. This study showed for the first time that the content of Mn, Co, Ni, Cu, Zn, Se, and Pb in pathological blood samples was significantly lower compared to the control, while opposite results were obtained for As, Cd, and U. Based on the classification model, the most important trace metals for discrimination of MNG and TC from the control group (CG) were Co and Zn, while Co, Zn, and Mn influenced the distinction of CG from TA. Moreover, it was found that Cu/Zn and U/Se ratios had significantly increased values in pathological blood samples leading to the possibility of establishing new circulating screening markers. These findings can represent significant translational information since these diseases are widespread and the diagnostic procedure is still difficult in many cases.

An overview of retrosternal goiter

Goiters tend to grow slowly and steadily over many years, occasionally reaching the mediastinum and extending through the thoracic inlet into the visceral compartment. In most cases, retrosternal goiters originate from the cervical portion of the thyroid. The incidence of retrosternal goiters varies considerably, ranging from 0.2 to 45% of all thyroidectomies, depending on the criteria used to define this type of goiter. Symptoms are generally related to the compressive nature of the mass on the adjacent structures, and most patients report some form of respiratory manifestation associated with the goiter. A diagnostic assessment usually includes an evaluation of thyroid function, chest radiography, and computed tomography. Fine-needle aspiration biopsy should be avoided in substernal areas of the goiter due to limited visibility and location of vital structures in this region. Treatment of retrosternal goiters is surgical, as medical therapy is generally unsuccessful in these cases.

Recombinant Human Thyrotropin-Stimulated Radioiodine Therapy in Patients with Multinodular Goiters: A Meta-Analysis of Randomized Controlled Trials

A potential reduction of goiter volume (GV) of recombinant human thyrotropin (rhTSH) on multinodular goiters (MNG) was previously reported but controversial. Hence we conducted a meta-analysis to estimate the effect of rhTSH-stimulated radioiodine therapy in patients with MNG. PubMed, Cochrane, CNKI, VIP, and Wanfang databases were searched. Mean difference (MD) and odds ratios with 95% confidence intervals (95% CI) were derived by using an inverse variance random-effects model and fixed-effects model, respectively. Six studies (n=237) were involved in the analysis. For 12 months follow up, high dose (>0.1 mg) of rhTSH significantly reduced GV (MD=17.61; 95% CI=12.17 to 23.04; p<0.00001) compared with placebo. No effective pooled results of low dose of rhTSH (<0.1 mg) were applicable for only one study included. For 6 months follow up, the source of heterogeneity was determined by subgroup and sensitivity analysis. High dose group showed vast improvement in GV reduction (MD=16.62; 95% CI=1.34 to 31.90; p=0.03). The reduction of low dose group compared with placebo was inferior to high dose group. No available data were obtained to assess the influence of rhTSH after 36 months follow up for the only included study. Hypothyroidism incidence was higher for rhTSH group. No publication bias was seen. High dose of rhTSH treatment-stimulated radioactive ¹³¹I therapy after 6 months and 12 months follow up had a better effect in reducing GV, but with higher incidence of hypothyroidism. Owing to the limited methodological quality, more clinical researches are warranted in the future.

Molecular Imaging in the Head and Neck: Diagnosis and Therapy

This article is a summary of the most up-to-date applications of radiopharmaceuticals to the diagnosis and therapy of benign and malignant diseases involving endocrine or neuroendocrine organs of the head and neck, focusing on radiotracers approved by the US Food and Drug Administration, such as I-123- and I-131-sodium iodide, F-18-fluorodeoxyglucose, Tc99m-sestamibi, as well as the more recently approved tracers Ga-68 DOTATATE and Lu-177 DOTATATE.

Graves' disease, multinodular goiter and subclinical hyperthyroidism

Subclinical hyperthyroidism is a common clinical entity, defined by serum TSH below the reference range, with normal FT4 and FT3 levels in an asymptomatic patient. Whether or not subclinical hyperthyroidism should be treated remains a matter of debate. Cross-sectional and longitudinal population-based studies demonstrate association of subclinical hyperthyroidism with risk of atrial fibrillation and osteoporosis, and with cardiovascular and all-cause mortality. However, there are no randomized clinical trials addressing whether long-term health outcomes are improved by treating subclinical hyperthyroidism; in the absence of evidence one way or the other, it seems appropriate to use decision trees taking account of TSH concentration and presence of risk factors (age>65 years or post-menopause, osteoporosis and cardiac disease).

Quality of Life in Patients Treated with Percutaneous Laser Ablation for Non-Functioning Benign Thyroid Nodules: A Prospective Single-Center Study

Objective

While many studies have reported that laser ablation (LA) for benign non-fuctioning thyroid nodules is efficacious in reducing nodular volume and neck symptoms, none have described changes in quality of life (QoL). The purpose of this study was to report post-LA changes in QoL in our cohort of patients.

Materials and Methods

Fourteen patients with benign thyroid nodules were involved in a prospective, single-center study and underwent a single session of LA. We evaluated the following: changes in nodule volume, thyroid function, and autoimmunity; adverse events during and after LA; changes in neck discomfort by means of a visual analogic scale (VAS) at one week and 1, 3, 6, and 12 months; and changes in QoL through the 13-scale Thyroid-specific Patient Reported Outcome (ThyPRO) questionnaire at 1, 3, 6, and 12 months. ThyPRO is a validated questionnaire for thyroid diseases, which consists of 13 scales with multiple-choice answers. They investigate several aspects of life that may be impaired by goiter-related compression symptoms, by esthetic alterations and by hypo- or hyperthyroidism.

Results

Nodule volume decrease was −37 ± 23%, −55 ± 22%, −53 ± 25%, −58 ± 25% (p < 0.01 vs. baseline) at the first, third, sixth, and twelfth month, respectively. No hypothyroidism or positivization of autoimmunity was observed. There were no major complications during or after LA. After LA, VAS scores improved significantly from 1 week onwards in 100% of patients, while a significant improvement was seen in the goiter symptoms score after one month, and in the general score and mean values of ThyPRO after six months. Scores on the other ThyPRO scales did not change significantly.

Conclusion

Laser ablation is safe and effective in reducing nodule volume and neck symptoms; this is confirmed by improvements in the goiter scale, general score, and mean values of ThyPRO and in the VAS score.

Recombinant human thyrotropin stimulated 131I treatment for multinodular goiter

The aim of the study was to investigate the effects of rhTSH stimulation before ¹³¹I treatment in patients with MNG.

METHODS

Sources included the Cochrane Library, MEDLINE, EMBASE, and SCOPUS database (all until January 2016). Randomized controlled trials (RCTs) that assessed the efficacy of rhTSH-stimulated ¹³¹I treatment compared to placebo or ¹³¹I treatment alone were collected. Two authors performed the data extraction independently.

RESULTS

Six RCTs involving 294 patients with MNG were included in this review. Altogether 168 patients were randomized to rhTSH-stimulated ¹³¹I therapy, and 126 to either placebo and ¹³¹I or ¹³¹I alone. rhTSH-stimulated ¹³¹I vs placebo and ¹³¹I or ¹³¹I alone for MNG showed no statistically significant difference in quality of life and all-cause mortality. rhTSH- (at a dose of 0.03 mg and above) stimulated ¹³¹I treatment for MNG showed significant benefits in thyroid volume reduction. ¹³¹I treatment with rhTSH stimulation at high doses (0.03 mg, 0.1 mg, 0.3 mg and 0.45 mg) for MNG caused significantly higher adverse effects and hypothyroidism.

CONCLUSIONS

The overall results indicated that using rhTSH at high doses of 0.03-0.45 mg before ¹³¹I therapy resulted in a greater TVR than ¹³¹I therapy alone for patients with non-toxic MNG. However, an increased incidence of adverse effects and hypothyroidism was observed in patients receiving high-dose of rhTSH pretreatment than in patients who received low-dose rhTSH pretreatment. Therefore, a dose of 0.03 mg rhTSH pretreatment before ¹³¹I therapy may be more potent than ¹³¹I alone in treating patients with non-toxic MNG who either had a contraindication for or declined surgery.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS, AMERICAN COLLEGE OF ENDOCRINOLOGY, AND ASSOCIAZIONE MEDICI ENDOCRINOLOGI MEDICAL GUIDELINES FOR CLINICAL PRACTICE FOR THE DIAGNOSIS AND MANAGEMENT OF THYROID NODULES--2016 UPDATE

Thyroid nodules are detected in up to 50 to 60% of healthy subjects. Most nodules do not cause clinically significant symptoms, and as a result, the main challenge in their management is to rule out malignancy, with ultrasonography (US) and fine-needle aspiration (FNA) biopsy serving as diagnostic cornerstones. The key issues discussed in these guidelines are as follows: (1) US-based categorization of the malignancy risk and indications for US-guided FNA (henceforth, FNA), (2) cytologic classification of FNA samples, (3) the roles of immunocytochemistry and molecular testing applied to thyroid FNA, (4) therapeutic options, and (5) follow-up strategy. Thyroid nodule management during pregnancy and in children are also addressed. On the basis of US features, thyroid nodules may be categorized into 3 groups: low-, intermediate-and high-malignancy risk. FNA should be considered for nodules ≤10 mm diameter only when suspicious US signs are present, while nodules ≤5 mm should be monitored rather than biopsied. A classification scheme of 5 categories (nondiagnostic, benign, indeterminate, suspicious for malignancy, or malignant) is recommended for the cytologic report. Indeterminate lesions are further subdivided into 2 subclasses to more accurately stratify the risk of malignancy. At present, no single cytochemical or genetic marker can definitely rule out malignancy in indeterminate nodules. Nevertheless, these tools should be considered together with clinical data, US signs, elastographic pattern, or results of other imaging techniques to improve the management of these lesions. Most thyroid nodules do not require any treatment, and levothyroxine (LT4) suppressive therapy is not recommended. Percutaneous ethanol injection (PEI) should be the first-line treatment option for relapsing, benign cystic lesions, while US-guided thermal ablation treatments may be considered for solid or mixed symptomatic benign thyroid nodules. Surgery remains the treatment of choice for malignant or suspicious nodules. The present document updates previous guidelines released in 2006 and 2010 by the American Association of Clinical Endocrinologists (AACE), American College of Endocrinology (ACE) and Associazione Medici Endocrinologi (AME).

Recombinant human thyrotropin stimulation prior to 131I therapy in toxic multinodular goitre with low radioactive iodine uptake

AIM

Stimulation with recombinant human thyrotropin (rhTSH) increases thyroid radioiodine uptake, and is an aid to ¹³¹I therapy in non-toxic multinodular goitre (MNG). However, there are not many studies using rhTSH prior to ¹³¹I in toxic multinodular goitre to improve hyperthyroidism and compressive symptoms.

MATERIAL AND METHOD

A prospective study was conducted on patients with MNG and hyperthyroidism. Patients were recruited consecutively and divided into group I, stimulated with 0.3mg of rhTSH before radioiodine therapy, and a control group or group II, without stimulation. Thyroid function, radioiodine thyroid uptake, thyroid weight, and compressive symptoms were measured, and patients were followed-up for 9 months.

RESULTS

Group I consisted of 16 patients (14 women), with a mean age 69.7 years, and group II with 16 patients (12 women), with a mean age 70.7 years. After stimulation with 0.3mg rhTSH in group I, ¹³¹I uptake (RAIU) at 24h increased by 78.4%, and the estimated absorbed dose by 89.3%. In group II, the estimated absorbed dose was lower than group I after stimulation with rhTSH (29.8Gy vs. 56.4Gy; P=0.001). At 9 months of follow-up, hyperthyroidism was controlled in 87.5% of patients in group I, and 56.2% in group II (P=0.049). The mean reduction in thyroid weight was higher in group I than in group II (39.3% vs. 26.9%; P=0.017), with a tendency towards subjective improvement of compressive symptoms in group I, although non-significant. Only 2 patients described tachycardias after rhTSH administration, which were resolved with beta-blockers.

CONCLUSION

Stimulation with 0.3mg of recombinant human thyrotropin prior to radioiodine therapy achieves a reduction in thyroid weight and functional improvement in patients with hyperthyroidism and multinodular goitre with low uptake, and with no need for hospital admission.

Etiopathology, clinical features, and treatment of diffuse and multinodular nontoxic goiters

Goiter, an enlargement of the thyroid gland, is a common problem in clinical practice associated with iodine deficiency, increase in serum thyroid-stimulating hormone (TSH) level, natural goitrogens, smoking, and lack of selenium and iron. Evidence suggests that heredity also has an important role in the etiology of goiter. The current classification divides goiter into diffuse and nodular, which may be further subdivided into toxic (associated with symptoms of hyperthyroidism, suppressed TSH or both), or nontoxic (associated with a normal TSH level). Nodular thyroid disease with the presence of single or multiple nodules requires evaluation due to the risk of malignancy, toxicity, and local compressive symptoms. Measurement of TSH, accurate imaging with high-resolution ultrasonography or computed tomography, and fine-needle aspiration biopsy are the appropriate methods for evaluation and management of goiter. This review discusses the clinical presentation, diagnostic evaluation, and treatment considerations of nontoxic diffuse and nodular goiters.

Which Is the Ideal Treatment for Benign Diffuse and Multinodular Non-Toxic Goiters?

Patients with large benign goiters often present local compressive symptoms that require surgical treatment, including dysphagia, neck tightness, and airway obstruction. In contrast, patients with such goiters who remain asymptomatic may be observed after exclusion of malignancy. The use of levothyroxine (LT4) to reduce the volume of the goiter is still a controversial treatment for large goiters, and the optimal surgical procedure for multinodular goiter is still debatable. Radioiodine is a safe and effective treatment option when used alone or in combination with recombinant human TSH. This review discusses current therapeutic options to treat diffuse and multinodular non-toxic benign goiters.

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

BACKGROUND

Recombinant human thyrotropin (rhTSH) can be used to enhance radioiodine therapy for shrinking multinodular goitre. The aim of this meta-analysis was to compare the effectiveness of rhTSH pretreatment and radioiodine therapy with that of radioiodine alone for treating benign nodular goitre.

METHODS

The PubMed, EMBASE, Cochrane Library, Scopus and ClinicalTrials.gov databases were searched to identify studies published before September 2014. A meta-analysis was performed to calculate the pooled effect size using random-effects models. The primary outcome was the reduction in thyroid volume. Secondary outcomes included thyroid function, extent of tracheal compression, radioactive iodine uptake, incidence of hypothyroidism and other complications.

RESULTS

Nine RCTs including 416 patients were selected. The reductions in thyroid volume were significantly greater in the rhTSH pretreatment groups than those in the radioiodine alone groups at 12 months (weighted mean difference: 14·42%; 95% CI: 4·51-24·34% in high-dose rhTSH vs radioiodine alone; weighted mean difference: 19·66%; 95% CI: 3·67-35·65% in low-dose rhTSH vs radioiodine alone). The incidence of hypothyroidism in the high-dose rhTSH groups was significantly higher than that in the radioiodine alone groups. No significant difference in the incidence of hypothyroidism occurred between the low-dose rhTSH groups and the radioiodine alone groups.

CONCLUSIONS

The overall results indicated that using rhTSH before radioiodine therapy resulted in a greater thyroid volume reduction than radioiodine therapy alone. An increased incidence of hypothyroidism was observed in patients receiving high-dose rhTSH. Low-dose rhTSH before radioiodine therapy is more efficacious than radioiodine therapy alone for treating nontoxic benign thyroid nodules.

Recombinant human TSH and radioactive iodine therapy in the management of benign multinodular goiter

Multinodular goiter (MNG) is a very common thyroid disorder determined by diverse goitrogenic factors, the most important one being iodine deficiency. The clinical presentation of a patient with MNG varies from a completely asymptomatic goiter to a life-threatening disease due to upper airway compression. Patients can develop underlying subclinical or overt hyperthyroidism due to autonomously hyperfunctioning nodules. In the absence of clinical, ultrasonographic, or cytological findings suggestive of malignancy, the best therapeutic approach for a patient with MNG will depend on the size and location of the goiter, the presence and severity of compressive symptoms, and the presence or absence of thyrotoxicosis. There is still no consensus regarding the treatment of atoxic MNGs. Hence, its optimal management remains controversial; possible therapies include levothyroxine (lT4), surgery, and radioactive iodine ((131)I). Suppressive treatment with lT4 is discouraged due to the development of sub-clinical or overt hyperthyroidism and to its low efficacy when compared with surgery or (131)I. Total thyroidectomy is effective; however, it is associated with the risk of surgical complications and is often refused by the patient. (131)I therapy is an alternative to thyroid surgery to reduce the size of benign MNGs. Based on the ability of recombinant human TSH (rhTSH) to more than double thyroid (131)I uptake, this compound has been evaluated as an adjuvant to (131)I in the treatment of MNG. Very small doses of rhTSH have been used in patients with MNG and few safety concerns have been observed, but the ideal dose, both effective and safe, is yet to be defined.

The role of radioiodine therapy in benign nodular goitre

For treatment of benign nodular goitre the choice usually stands between surgery and (131)I therapy. (131)I therapy, used for 30 years for this condition, leads to a goitre volume reduction of 35-50% within 1-2 years. However, this treatment has limited efficacy if the thyroid (131)I uptake is low or if the goitre is large. Recombinant human TSH (rhTSH)-stimulated (131)I therapy significantly improves goitre reduction, as compared with conventional (131)I therapy without pre-stimulation, and adverse effects are few with rhTSH doses of 0.1 mg or lower. RhTSH-stimulated (131)I therapy reduces the need for additional therapy due to insufficient goitre reduction, but the price is a higher rate of hypothyroidism. Another approach with rhTSH-stimulation is to reduce the administered (131)I activity by a factor that equals the increase in the thyroid (131)I uptake. Using this approach, radiation exposure is considerably reduced while the goitre reduction is similar to that obtained with conventional (131)I therapy.

Long-term efficacy of modified-release recombinant human thyrotropin augmented radioiodine therapy for benign multinodular goiter: results from a multicenter, international, randomized, placebo-controlled, dose-selection study

BACKGROUND

Enhanced reduction of multinodular goiter (MNG) can be achieved by stimulation with recombinant human thyrotropin (rhTSH) before radioiodine ((131)I) therapy. The objective was to compare the long-term efficacy and safety of two low doses of modified release rhTSH (MRrhTSH) in combination with (131)I therapy.

METHODS

In this phase II, single-blinded, placebo-controlled study, 95 patients (57.2 ± 9.6 years old, 85% women, 83% Caucasians) with MNG (median size 96.0 mL; range 31.9-242.2 mL) were randomized to receive placebo (n=32), 0.01 mg MRrhTSH (n=30), or 0.03 mg MRrhTSH (n=33) 24 hours before a calculated (131)I activity. Thyroid volume (TV) and smallest cross-sectional area of trachea (SCAT) were measured (by computed tomography scan) at baseline, six months, and 36 months. Thyroid function and quality of life (QoL) was evaluated at three-month and yearly intervals respectively.

RESULTS

At six months, TV reduction was enhanced in the 0.03 mg MRrhTSH group (32.9% vs. 23.1% in the placebo group; p=0.03) but not in the 0.01 mg MRrhTSH group. At 36 months, the mean percent TV reduction from baseline was 44 ± 12.7% (SD) in the placebo group, 41 ± 21.0% in the 0.01 mg MRrhTSH group, and 53 ± 18.6% in the 0.03 mg MRrhTSH group, with no statistically significant differences among the groups, p=0.105. In the 0.03 mg MRrhTSH group, the subset of patients with basal (131)I uptake <20% had a 24% greater TV reduction at 36 months than the corresponding subset of patients in the placebo group (p=0.01). At 36 months, the largest relative increase in SCAT was observed in the 0.03 mg MRrhTSH group (13.4 ± 23.2%), but this was not statistically different from the increases observed in the placebo or the 0.01 mg MRrhTSH group (p=0.15). Goiter-related symptoms were reduced and QoL improved, without any enhanced benefit from using MRrhTSH. At three years, the prevalence of permanent hypothyroidism was 13%, 33%, and 45% in the placebo, 0.01 mg, and 0.03 mg MRrhTSH groups respectively. The overall safety profile of the study was favorable.

CONCLUSIONS

When used as adjuvant to (131)I, enhanced MNG reduction could not be demonstrated with MRrhTSH doses ≤ 0.03 mg, indicating that the lower threshold for efficacy is around this level.

Radioiodine therapy in benign thyroid diseases: effects, side effects, and factors affecting therapeutic outcome

Radioiodine ((131)I) therapy of benign thyroid diseases was introduced 70 yr ago, and the patients treated since then are probably numbered in the millions. Fifty to 90% of hyperthyroid patients are cured within 1 yr after (131)I therapy. With longer follow-up, permanent hypothyroidism seems inevitable in Graves' disease, whereas this risk is much lower when treating toxic nodular goiter. The side effect causing most concern is the potential induction of ophthalmopathy in predisposed individuals. The response to (131)I therapy is to some extent related to the radiation dose. However, calculation of an exact thyroid dose is error-prone due to imprecise measurement of the (131)I biokinetics, and the importance of internal dosimetric factors, such as the thyroid follicle size, is probably underestimated. Besides these obstacles, several potential confounders interfere with the efficacy of (131)I therapy, and they may even interact mutually and counteract each other. Numerous studies have evaluated the effect of (131)I therapy, but results have been conflicting due to differences in design, sample size, patient selection, and dose calculation. It seems clear that no single factor reliably predicts the outcome from (131)I therapy. The individual radiosensitivity, still poorly defined and impossible to quantify, may be a major determinant of the outcome from (131)I therapy. Above all, the impact of (131)I therapy relies on the iodine-concentrating ability of the thyroid gland. The thyroid (131)I uptake (or retention) can be stimulated in several ways, including dietary iodine restriction and use of lithium. In particular, recombinant human thyrotropin has gained interest because this compound significantly amplifies the effect of (131)I therapy in patients with nontoxic nodular goiter.

Prestimulation with recombinant human thyrotropin (rhTSH) improves the long-term outcome of radioiodine therapy for multinodular nontoxic goiter

OBJECTIVE

The objective of the study was to evaluate the long-term outcome of recombinant human TSH (rhTSH)-augmented radioiodine ((131)I) therapy for benign multinodular nontoxic goiter.

PATIENTS AND METHODS

Between 2002 and 2005, 86 patients with a multinodular nontoxic goiter were treated with (131)I in two randomized, double-blind, placebo-controlled trials. (131)I-therapy was preceded by 0.3 mg rhTSH (n = 42) or placebo (n = 44). In 2009, 80 patients completed a follow-up (FU) visit, including determination of thyroid volume, thyroid function, and patient satisfaction by a visual analog scale.

RESULTS

In both groups, thyroid volume was further reduced from 1 yr to final FU (71 months). The mean goiter volume reductions obtained at 1 yr and final FU [59.2 ± 2.4% (sem) and 69.7 ± 3.1%, respectively] in the rhTSH group were significantly greater than those obtained in the (131)I-alone group (43.2 ± 3.7 and 56.2 ± 3.6%, respectively, P = 0.001 and P = 0.006), corresponding to a gain of 24% at final FU. At last FU the mean reduction in compression visual analog scale score was significantly greater in patients receiving rhTSH (P = 0.049). Additional therapy (thyroid surgery or (131)I) was required more often in the placebo group (nine of 44) compared with the rhTSH group (two of 42) (P = 0.05). The prevalence of hypothyroidism at 1 yr [9 and 43% in the placebo and rhTSH groups, respectively (P < 0.0001)] increased to 16 and 52%, respectively, at final FU (P = 0.001).

CONCLUSION

Enhanced goiter volume reduction with rhTSH-augmented (131)I therapy improves the long-term reduction in goiter-related symptoms and reduces the need for additional therapy compared with plain (131)I therapy. Overall patient satisfaction is benefited, despite a higher rate of permanent hypothyroidism.

Approach to and treatment of goiters

The main causes of simple diffuse goiter (SDG) and multinodular goiter (MNG) are iodine deficiency, increase in serum thyroid-stimulating hormone (TSH) level, natural goitrogens, smoking, chronic malnutrition, and lack of selenium, iron, and zinc. Increasing evidence suggests that heredity is equally important. Treatment of SDG and MNG still focuses on L-thyroxine-suppressive therapy surgery. Radioiodine alone or preceded by recombinant human TSH stimulation is widely used in Europe and other countries. Each of these therapeutic options has advantages and disadvantages, with acute and long-term side effects.

Non-surgical approach to the benign nodular goiter: new opportunities by recombinant human TSH-stimulated 131I-therapy

The optimal treatment strategy in a goiter patient depends--among other factors--on goiter size, the degree of cosmetic or compressive symptoms, the age of the patient, the impact on the upper airways, the wish to maintain normal thyroid function, the ability of the thyroid gland to take up (131)I, and the possibility of thyroid malignancy. When treatment is warranted in a patient with benign goiter, the choice usually stands between surgery and (131)I-therapy. Focal destructive treatment, by ethanol sclerotherapy or interstitial laser photocoagulation, may be considered in patients with a solitary benign nodule. If thyroid hyperfunction due to nodular autonomy is the dominant problem, life-long anti-thyroid drug treatment may be relevant in elderly individuals. With the advent of recombinant human TSH (rhTSH) stimulation the goiter reduction following (131)I-therapy is significantly enhanced and this treatment is of particular benefit, as compared with conventional (131)I-therapy, in patients with a low baseline thyroid (131)I uptake and a large goiter. If the rhTSH dose does not exceed 0.1 mg the risk of temporary hyperthyroidism and acute thyroid swelling is low. Since patient satisfaction seemingly is not improved by the greater goiter reduction obtained by rhTSH-stimulated (131)I-therapy, and permanent hypothyroidism is more frequent, it may be more relevant to reduce the administered radioactivity equivalent to the rhTSH-induced increase in the thyroid (131)I uptake. Future large-scale well-controlled studies should explore this strategy, with focus on cost-benefit and quality of life. A major hindrance of widespread and routine use of rhTSH-stimulated (131)I-therapy is its present status as an off-label treatment.

A randomized trial evaluating a block-replacement regimen during radioiodine therapy

BACKGROUND

Lack of consensus regarding the antithyroid drug regimen in relation to radioiodine ((131) I) therapy of hyperthyroidism prompted this randomized trial comparing two strategies.

DESIGN

Patients with Graves' disease (GD, n = 51) or toxic nodular goitre (TNG, n = 49) were randomized to (131) I either 8 days following discontinuation of methimazole (-BRT, n = 52, median dose: 5 mg) or while on a continuous block-replacement regimen (+BRT, n = 48, median dose 15 mg methimazole and 100 μg levothyroxine). results: Patients in the +BRT group required more radioactivity. In this group, thyroid function did not change in the early post (131) I period, while serum-free T3 index was higher in the -BRT group (P < 0·05). One year posttherapy, the fraction of cured patients (euthyroid or hypothyroid) was 48% and 61% in the +BRT and -BRT group, respectively (P = 0·014 unadjusted; P = 0·004 adjusted), but the outcome depended on the type of disease. In GD, treatment failure in the +BRT group correlated positively with the 24-h thyroid (131) I uptake (P = 0·017), while no correlations existed in the -BRT group. In addition to +BRT allocation, patients with TNG were at higher risk of treatment failure with lower thyroid radiation doses (P = 0·048), higher doses of methimazole (P = 0·026) and lower levels of serum TSH (P = 0·009).

CONCLUSIONS

A continuous block-replacement regimen results in a stable thyroid function during (131) I therapy but is hampered by the higher amounts of radioactivity required. The study demonstrates that the outcome in GD is highly unpredictable, while treatment failure in patients with TNG is correlated with a number of factors.

Radioiodine therapy of benign non-toxic goitre. Potential role of recombinant human TSH

This review provides an update on recombinant human TSH (rh-TSH) augmented radioiodine (¹³¹I) therapy and outlines its potential role in the treatment of symptomatic benign multinodular non-toxic goitre. In some countries, ¹³¹I has been used for three decades to reduce the size of nodular goitres. The feasibility of ¹³¹I therapy depends on an adequate thyroid ¹³¹I uptake. Based on a two-fold increase in thyroid ¹³¹I uptake, superiority studies have convincingly demonstrated that the absorbed thyroid ¹³¹I dose can be increased without increasing the administered ¹³¹I activity, resulting in a 35-56% amplification of goitre reduction at one-year post radioiodine compared to conventional (without rh-TSH) ¹³¹I therapy. Although patient satisfaction is not improved at one-year, this approach facilitates tracheal decompression and is particularly promising in large goitres. The majority of multinodular non-toxic goitre patients may not require amplified goitre reduction. But as an alternative strategy, rh-TSH allows up to 80% reduction of the therapeutic ¹³¹I activity while still achieving goitre reduction comparable to that of conventional ¹³¹I therapy and maintaining high patient satisfaction. The dose-reduction (equality) strategy is attractive in terms of minimizing post-therapeutic restrictions and in reducing the potential risk of radiation-induced malignancy. Adverse effects like temporary thyroid swelling and thyroid hormone excess are to a large extent dose-dependent and generally 0.1mg rh-TSH or less is well tolerated. Based on these results we conclude that rh-TSH augmented ¹³¹I therapy is a promising new therapeutic principle allowing the tailoring of an optimal ¹³¹I therapy on the individual level.

Serum thyroxine and age--rather than thyroid volume and serum TSH--are determinants of the thyroid radioiodine uptake in patients with nodular goiter

BACKGROUND

Radioiodine (131I) therapy is widely used for treatment of non-toxic goiters. A limitation for this treatment is a low thyroid radioiodine uptake (RAIU), often encountered in these patients.

AIM

To estimate the impact of various factors on the thyroid RAIU.

METHODS

We examined prospectively 170 patients (146 females; age range: 22-87 yrs) with nodular goiter (median 64 ml, range: 20-464 ml) selected for 131I therapy. Serum TSH was sub-normal in 42.4%. None were treated with anti-thyroid drugs. The thyroid RAIU was determined at 24h and 96 h. The goiter volume was measured by ultrasound (no.=127), or by magnetic resonance imaging (no.=43).

RESULTS

The 24h and the 96 h RAIU were 34.2 ± 9.8(SD)% (range: 11.4-66.0%) and 34.0 ± 10.0% (range: 10.5-60.9%), respectively. Sixty-one patients had a 24h RAIU <30% and these individuals were older than patients with a 24h RAIU ≥ 30% (median 58 vs 51 yrs, p=0.02). These two subgroups did not differ significantly in other variables. Overall, the 24h RAIU was positively correlated to the serum (s) free T4-index (r=0.20, p=0.01), and negatively to age (r=-0.18, p=0.02), but not significantly related to serum TSH or thyroid volume. Age correlated positively with thyroid volume (r=0.31, p < 0.001). In a regression analysis, s-free T4-index and age remained as the only determinants of the 24h and the 96 h RAIU.

CONCLUSIONS

In patients with a symptomatic nodular goiter, serum T4 and age are the major determinants of the thyroid RAIU. A sub-normal serum TSH is not a marker of a compromised thyroid RAIU but reflects that the iodine is confined to a few 'hot spots'.

Recombinant human thyrotropin-stimulated radioiodine therapy of nodular goiter allows major reduction of the radiation burden with retained efficacy

CONTEXT AND OBJECTIVE

Stimulation with recombinant human TSH (rhTSH) before radioiodine (131I) therapy augments goiter volume reduction (GVR). Observations indicate that rhTSH has a preconditioning effect beyond increasing thyroid (131)I uptake. We test the hypothesis that an equivalent GVR might be obtained by an absorbed thyroid dose well below what has been used previously.

PATIENTS AND DESIGN

In a double-blinded setup, 90 patients (78 women; median age, 52 yr; range, 22-83) with a nontoxic nodular goiter (median size, 63 ml; range, 25-379 ml) were randomized to either 0.1 mg rhTSH (n=60) followed by a thyroid dose of 50 Gy or placebo followed by 100 Gy (n=30).

RESULTS

At 12 months, the mean relative GVR in the placebo and the rhTSH group was identical (35+/-3%; P=0.81). The median administered 131I-activity was 170 MBq (45-1269) in the rhTSH group and 559 MBq (245-3530) in the placebo group (70% reduction, P<0.0001). According to the official radiation regulation, hospitalization was required in 14 patients in the placebo group vs. one patient in the rhTSH group (P<0.0001). In both groups, goiter-related symptoms were effectively relieved in the majority of patients. The prevalence of myxedema (10%) did not differ among groups.

CONCLUSIONS

This is the first study to demonstrate that rhTSH not only increases the thyroid 131I uptake, but per se potentiates the effect of 131I-therapy, allowing a major reduction of the 131I-activity without compromising efficacy. This approach is attractive in terms of minimizing posttherapeutic restrictions and in reducing the potential risk of radiation-induced malignancy.

Dose-dependent acute effects of recombinant human TSH (rhTSH) on thyroid size and function: comparison of 0.1, 0.3 and 0.9 mg of rhTSH

CONTEXT

Recombinant human TSH (rhTSH) is used to augment the effect of radioiodine therapy for nontoxic multinodular goitre. Reports of acute thyroid swelling and hyperthyroidism warrant safety studies evaluating whether these side-effects are dose dependent.

OBJECTIVE

To determine the effects on thyroid size and function of various doses of rhTSH.

DESIGN

In nine healthy male volunteers, the effect of placebo, 0.1, 0.3 and 0.9 mg of rhTSH was examined in a paired design including four consecutive study rounds.

MAIN OUTCOME MEASURES

Main outcome measures were evaluated at baseline, 24 h, 48 h, 96 h, 7 days and 28 days after rhTSH and included: Thyroid volume (TV) estimation by planimetric ultrasound, and thyroid function by serum TSH, free T3, free T4 and Tg levels.

RESULTS

Following placebo or 0.1 mg rhTSH, the TV did not change significantly from baseline at any time. At 24 and 48 h after administration of 0.3 mg rhTSH, the TV increased by 37.4 +/- 12.3% (SEM) (P = 0.03) and 45.3 +/- 16.1% (P = 0.05) respectively. After 0.9 mg rhTSH, the TV increased by 23.3 +/- 5.8% (P = 0.008) and 35.5 +/- 18.4% (P = 0.02) respectively. The increase in serum FT3, FT4 and thyroglobulin (Tg) was greater when administering 0.3 mg compared with 0.1 mg (P = 0.02) and when administering 0.9 mg compared with 0.3 mg (P = 0.02). After 0.1 mg rhTSH, the increase in FT3 and Tg was not significantly different from placebo whereas the FT4 increase was significantly higher (P = 0.02 compared with placebo).

CONCLUSIONS

In healthy individuals, rhTSH-induced thyroid swelling and hyperthyroidism is rapid and dose dependent. If valid for patients with goitre, our results suggest that these adverse effects are unlikely to be of clinical significance, following doses of rhTSH of 0.1 mg or less.

A 30-year perspective on radioiodine therapy of benign nontoxic multinodular goiter

PURPOSE OF REVIEW

There is no consensus on the ideal treatment of patients with a benign nontoxic multinodular goiter. In some European countries, (131)I therapy has replaced surgery as the treatment of choice in these patients. Recombinant human thyrotropin (rhTSH) is a very potent stimulator of the thyroid gland and this review focuses on rhTSH-stimulated (131)I therapy.

RECENT FINDINGS

The concept of rhTSH-stimulated (131)I therapy has been tested in several trials during the last 8 years. With this treatment, the goiter reduction is improved by 35-55%, compared with (131)I therapy without rhTSH stimulation. RhTSH prestimulation is particularly beneficial in patients with very large goiters and in those with a low baseline thyroid (131)I uptake. In addition, this therapy facilitates tracheal decompression leading to improved respiratory function. RhTSH-stimulated (131)I therapy results in a higher rate of permanent hypothyroidism, whereas other side-effects are very modest when using a rhTSH dose of 0.1 mg or below.

SUMMARY

RhTSH-stimulated radioiodine therapy of benign nontoxic multinodular goiter is still an off-label use but several trials have shown that this treatment is significantly more effective than (131)I therapy without rhTSH. However, no trial has yet compared (131)I therapy and surgery head-to-head, and future trials should include evaluation of quality of life and cost.

Radioiodine treatment for non-toxic goitre

There is no ideal treatment for benign multinodular goitre. Besides surgery, which is recommended for large goitres or when malignancy cannot be excluded, the non-surgical treatment options are levothyroxine therapy and radioiodine ((131)I) therapy. Conventional (131)I therapy [without recombinant human thyroid-stimulating hormone (rhTSH)] has been used for more than a decade in symptomatic non-toxic multinodular goitre, and although it does lead to significant thyroid volume reduction, relatively high activities of radioiodine are needed because of a frequent finding of a low thyroid radioiodine uptake. rhTSH, even when used in very small doses in combination with (131)I therapy, enhances the thyroid volume reduction at lower (131)I activities by doubling the thyroid radioiodine uptake. However, before rhTSH stimulation can be routinely used by clinicians to optimise the (131)I therapy in multinodular goitre, aspects of this association, such as the cost-benefit and optimum rhTSH dose and safety, will have to be sufficiently clarified.

Therapy: a new nonsurgical therapy option for benign thyroid nodules?

Despite the increasing implementation of iodization programs, benign nodular thyroid disease will remain a prevalent therapeutic concern for decades. recent research suggests that nonsurgical therapy, including radioactive iodine, radiofrequency thermal ablation and percutaneous laser ablation, might have a role in the treatment of symptomatic patients.

High prevalence of side effects after recombinant human thyrotropin-stimulated radioiodine treatment with 30 mCi in patients with multinodular goiter and subclinical/clinical hyperthyroidism

BACKGROUND

Treatment of multinodular goiters (MNGs) is highly controversial. Radioiodine (RAI) therapy is a nonsurgical alternative for the elderly who decline surgery. Recently, recombinant human thyrotropin (rhTSH) has been used to augment RAI uptake and distribution. In this study, we determined the outcome of 30 mCi RAI preceded by rhTSH (0.1 mg) in euthyroid (EU) and hyperthyroid (subclinical/clinical) patients with large MNGs.

METHODS

This was a prospective cohort study. Forty-two patients (age, 43-80 years) with MNGs were treated with 30 mCi RAI after stimulation with 0.1 mg of rhTSH. Patients were divided into three groups, according to thyroid function: EU (n = 18), subclinically hyperthyroid (SC-H, n = 18), and clinically hyperthyroid (C-H, n = 6). All patients underwent a 90-day low-iodine diet before treatment, and those with clinical hyperthyroidism received methimazole 10 mg daily for 30 days. Serum TSH, free thyroxine (FT4), total triiodothyronine (TT3), and thyroglobulin were measured at baseline and at 24, 48, 72, 168 hours, and 1, 3, 6, 9, 12, 18, 24, and 36 months after therapy. Thyroid volume was assessed by computed tomography at baseline and every 6 months.

RESULTS

Patients had high iodine urinary excretion (308 +/- 108 microg I/L) at baseline. TSH levels at baseline were within the normal range (1.5 +/- 0.7 microU/mL) in the EU group and suppressed (<0.3 microU/mL) in the SC-H and C-H groups. After rhTSH, serum TSH peaked at 24 hours reaching 12.4 +/- 5.85 microU/mL. After RAI administration, patients in both hyperthyroid groups had a higher increase in FT4 and TT3 compared with those in the EU group (p < 0.001). Thyroglobulin levels increased equally in all three groups until day 7. Thyroid volume decreased significantly in all patients. Side effects were more common in the SC-H and C-H groups (31.4% and 60.4%, respectively) compared with EU patients (17.8%). Permanent hypothyroidism was more prevalent in the EU group (50%) compared with the SC-H (11%) and C-H (16.6%) groups.

CONCLUSIONS

Patients with MNG may have subclinical and clinical nonautoimmune iodine-induced hyperthyroidism. Despite a low-iodine diet and therapy with methimazole, hyperthyroid patients have a significantly higher increase in FT4 and TT3 levels after RAI ablation. This can lead to important side effects related mostly to the cardiac system. We strongly advise that patients with SC-H and C-H be adequately treated with methimazole and low-iodine diet aiming to normalize their hyperthyroid condition before rhTSH-stimulated treatment with RAI.

Long-term outcome of low-activity radioiodine administration preceded by adjuvant recombinant human TSH pretreatment in elderly subjects with multinodular goiter

Background

Large multinodular goiter (MNG) in elderly people is a common finding which can require intervention. The long-term effect of radioiodine therapy on thyroid volume (TV) and function after recombinant human (rh) TSH pre-treatment was evaluated.

Methods

After baseline evaluation, 40 subjects over 60 years old with a large MNG were treated with ¹³¹I up to the activity of 600 MBq. Nineteen patients were pretreated with rhTSH (0.1 mg on 2 consecutive days; group 1) while 21 subjects underwent treatment without rhTSH pretreatment (group 2). TV was monitored every 6–12 months by ultrasonography. The median follow-up period was 36 months.

Results

At the baseline, the groups matched in terms of TV, 24-h radioiodine uptake (RAIU), urinary iodine and neck complaints. The number of subjects pretreated with anti-thyroid drugs was significantly (P = 0.01) greater in group 2 than in group 1; TSH was more suppressed (P = 0.003) and f-T3 was more elevated (P = 0.005) in group 2 than in group 1 patients. RhTSH increased 24-h RAIU in group 1 up to the baseline level observed in group 2. The ¹³¹I activity administered was similar in both groups. Adverse events were slight and similar in both groups. A permanent post-radioiodine toxic condition was reported only in 2 patients in group 2. After radioiodine therapy, hypothyroidism was observed in significantly more group 1 patients than group 2 patients (P = 0.002). While TV was reduced in both groups, the percentage TV reduction recorded at the last examination was significantly higher (P = 0.03) in group 1 than in group 2. MNG-related complaints were significantly reduced in both group 1 (P = 0.0001 vs baseline) and group 2 (P = 0.001) patients.

Conclusion

Low radioiodine activities after pretreatment with low-dosage rhTSH are able to reduce TV and improve MNG-related symptoms in elderly subjects.