Long-Term Follow-up of Patients With Autonomous Thyroid Nodules Treated With Radioiodine.

PURPOSE: This article aims to describe the presentation of Plummer disease and its evolution after radioiodine treatment and determine factors that may influence treatment efficacy. PATIENTS AND METHODS: The sample included retrospective medical records of 165 adult patients with toxic nodular goiter treated with radioiodine between 1997 and 2017, followed up at a single thyroid center. RESULTS: The efficacy of treatment with a single dose of radioiodine was higher than 90%. The mean radioiodine activity was 28.9 ± 3.4 mCi. The mean time between radioiodine performance and hyperthyroidism resolution was 3.6 ± 3.0 months, ranging from 1-12 months. After the first year, 33.9% of the patients were under hypothyroidism, 59.4% under euthyroidism, and 6.7% under hyperthyroidism. Among the nonresponders, the variables that showed statistical difference were the presence of multinodular goiter and the radioiodine activity (mean, 25.5 ± 6.5 mCi; median, 30 [15-30 mCi]). The cumulative rate of hypothyroidism was 48.9% over 20 years of follow-up. CONCLUSIONS: Radioiodine therapy is an effective and safe treatment. In Plummer disease, high rates of euthyroidism are expected after the radioiodine treatment. Therapeutic failure was observed mainly in patients with larger multinodular goiters treated with lower doses of radioiodine. The evolution to hypothyroidism was mostly observed in younger patients with larger and uninodular goiters.

Radioiodine versus radiofrequency ablation to treat autonomously functioning thyroid nodules: a systematic review and comparative meta-analysis.

PURPOSE: Radioiodine (RAI) is a well-established first-line therapy for autonomously functioning thyroid nodules (AFTN). Radiofrequency ablation (RFA) is a minimally invasive procedure that has been proposed as an alternative treatment option for hyperthyroidism caused by AFTN. Although RFA has been shown to be useful for reducing nodule volume and improving TSH levels in AFTN, no comprehensive comparative clinical studies have been proposed to evaluate the overall response to RFA treatment. The aim of this comparative systematic review and meta-analysis was to evaluate the response of RAI and RFA treatments in AFTN. METHODS: A systematic search strategy was applied in PubMed, Web of Science, Scopus, Cochrane Library, and ClinicalTrials.gov until July 2023 without time or language restrictions. Studies investigating the response to RAI and/or RFA treatment in AFTN patients 6 and/or 12 months after treatment were included. The risk of bias was assessed based on the study design. Random-effect models were used for the meta-analysis. RESULTS: Twenty-three articles (28 reports) met the inclusion criteria and were included in the study. Overall, RAI therapy was found to have a significantly higher treatment response (94%) than RFA (59%), although the volume of AFTNs was reduced to a similar extent. In the direct comparison (n = 3 studies), RFA showed a higher risk of non-response than RAI (RR, 1.24; 95% CI, 0.94-1.63; z = 1.55; p = 0.12). CONCLUSIONS: Our results demonstrate the superiority of RAI over RFA in terms of success rates and safety profile and confirm RAI as the first choice for the treatment of AFTNs.

Initial ablation radio predicting volume reduction from microwave ablation of benign thyroid nodules.

OBJECTIVE: Our research sought to investigate the relationship between initial ablation ratio (IAR) and internal composition of benign thyroid nodules treated by microwave ablation (MWA). MATERIALS AND METHODS: Patients who underwent MWA at the Affiliated Hospital of Jiangsu University from January 2018 to December 2022 were enrolled in our research. All the patients were followed up for at least one year. We analyzed the relationship between IAR at 1 month of solid nodules (solid >90%), predominantly solid nodules (90% >solid > 75%), mixed solid alongside cystic nodules (75% >solid > 50%) as well as volume reduction rate (VRR) at 1, 3, 6 and 12 months follow-up. OBJECTIVE: The mean IAR of the solid nodules (solid >90%) was 94.32±7.87%,#x0025;, that of the predominantly solid nodules (90% >solid > 75%) and mixed solid alongside cystic nodules (75% >solid > 50%) were 86.51±6.66% and 75.19±4.97%,#x0025;, respectively. Almost all the thyroid nodules were significantly decreased in size after MWA. After 12 months of MWA treatment, the average volume of the aforementioned thyroid nodules decreased from 8.69±8.79 to 1.84±3.11 ml, 10.94±9.07 to 2.58±3.34 ml, 9.92±6.27 to 0.25±0.42 ml, respectively. The mean symptom and cosmetic scores of the nodules showed significant (p < 0.000) improvement. The rates of the complications or side effects of MWA against the above-mentioned nodule types were 8.3% (3/36), 3.2% (1/31) and 0% (0/36), respectively. CONCLUSIONS: The application of the IAR to quantify the success rate of thyroid nodule microwaves in the short term demonstrated that IAR was related to the internal components of the nodule. Although the IAR was not high when the thyroid component was mixed solid and cystic nodules (75% >solid > 50%), the final therapeutic effect was still satisfactory.

Predictors of Hypothyroidism Following Empirical Dose Radioiodine in Toxic Thyroid Nodules: Real-Life Experience.

OBJECTIVE: We aimed to determine the factors predicting hypothyroidism after radioactive iodine (RAI) treatment in patients with toxic adenoma and toxic multinodular goiter. METHODS: We retrospectively collected the data of 237 patients with toxic multinodular goiter or toxic adenoma who had consecutively received RAI treatment between 2014 and 2020 at 2 medical centers. Patients who received the second RAI treatment and whose medical records could not be accessed were excluded from the study. Finally, 133 patients were included in the study. RAI was administered at an empirical dose of 15 or 20 mCi. RESULTS: The median age of the 133 participants was 69 years (interquartile range, 62-75 years), and 64.7% of the participants were women. A total of 42.1% of the patients had toxic adenoma, whereas 57.9% of patients had toxic multinodular goiter. The median follow-up was 24 months (interquartile range, 11-38 months). During the follow-up, 61.7% of patients became euthyroid, 30.8% developed hypothyroidism, and 7.5% remained hyperthyroid. The median month of hypothyroidism onset was 4 months (interquartile range, 2-9 months). Regression analysis revealed 2 factors that could predict hypothyroidism: thyroid-stimulating hormone (odds ratio, 2.548; 95% CI, 1.042-6.231; P = .04) and thyroid volume (odds ratio, 0.930; 95% CI, 0.885-0.978; P = .005). CONCLUSION: Overall, 30.8% of the cases developed hypothyroidism after the RAI treatment. Approximately 78% of hypothyroidism developed within the first 10 months. The risk of hypothyroidism was higher in patients with higher thyroid-stimulating hormone and smaller thyroid volume.

Predictor Analysis in Radiofrequency Ablation of Benign Thyroid Nodules: A Single Center Experience.

Purpose: To confirm the efficacy of ultrasound (US) guided radiofrequency ablation (RFA) in the treatment of benign thyroid nodules, we evaluated as primary outcome the technical efficacy and clinical success in a single center dataset. The secondary outcome was to find a correlation between nodules' pre-treatment features and volume reduction rate (VRR) ≥75% at 12 months after RFA and during follow-up period. Methods: This retrospective study included 119 consecutive patients (99 females, 20 males, 51.5 ± 14.4 years) with benign thyroid nodules treated in our hospital between October 2014 and December 2018 with a mean follow-up of 26.8 months (range 3-48). Clinical and US features before and after RFA were evaluated by a US examination at 1, 3, 6, 12 months and annually thereafter up to 48 months. Results: The median pre-treatment volume was 22.4 ml; after RFA we observed a statistically significant volume reduction from the first month (11.7 ml) to the last follow-up (p < 0.001 for all follow-up times). The median VRR was 47.1, 55.3, 61.2, 67.6, 72.8, 71.3, and 62.9% at 1, 3, 6, 12, 24, 36, and 48 months of follow-up respectively, showing a progressive significant improvement up to 24 months (VRRs 1 vs 3 months, 3 vs 6 months and 6 vs 12 months p < 0.001, 12 vs 24 months p = 0.05) while no differences at 24 vs 36 and 36 vs 48 months were observed. Symptoms improved significantly (complete resolution 64.35%, partial resolution 35.65%), and neck circumference was reduced as compared to pre-treatment (p < 0.001). Lower pre-treatment neck circumference (37.5 vs 36.0 cm, p = 0.01) was a positive predictor of VRR ≥75% at 12 months. Macrocystic echostructure (HR 2.48, p 0.046) and pre-treatment volume >22.4 ml (HR 0.54, p 0.036) were found to be independent positive and negative predictors of VRR ≥75% respectively. One-month post RFA VRR ≥50% represented the best positive predictor of technical success. Conclusions: This study confirmed the efficacy of RFA in the treatment of benign thyroid nodules. In particular we show that by selecting macrocystic nodules smaller than 22.4 ml better long-term response can be achieved, which is predicted by an early shrinkage of the nodule.

Microwave ablation of autonomously functioning thyroid nodules: a comparative study with radioactive iodine therapy on the functional treatment success.

INTRODUCTION: The objective of this study was to compare the efficiency of microwave ablation (MWA) and radioactive iodine (RAI) in the treatment of toxic adenoma (TA), and to investigate the functional treatment success of the used modalities for its remission. MATERIAL AND METHODS: Treatment outcomes- thyroid hormone levels and nodule characteristics- of 30 patients (23:7 F:M; 52.77 ± 11.13 years) treated by MWA were compared with the those of 35 patients (24:11 F:M; 61.43 ± 12.60 years) treated by RAI. The baseline characteristics of TAs, which are gender and pre volume, were analogous and did not show any statistical significance (p > 0.05). Thyroid hormone levels of patients treated with two different methods were measured after 9 months, and the obtained results were compared. RESULTS: Although there was no statistically significant difference in the nodule volume (p > 0.05), there was a greater volume reduction rate (VRR%) in the group treated with MWA rather than RAI (p < 0.05) at the end of the follow-up. In the MWA group, there was a higher increase in FT3 than in the RAI group (p < 0.05). Furthermore, no statistically significant difference in TSH (p = 0.124) and FT4 (p = 0.144) levels of the patients as treatment outcomes was observed. The therapeutic success was accomplished in 18/30 (60%) of the MWA group and in 24/35 (68.6%) of the RAI group. CONCLUSIONS: Therapeutic success of MWA and RAI did not show any statistically significant difference (p = 0.471). However, the development of hypothyroidism in 7 of 35 patients treated with RAI was observed. On the other hand, no case of post-treatment hypothyroidism was observed in patients treated with MWA. In this regard, MWA could be a great alternative to RAI due to its advantages in terms of non-exposure to radiation and lower risk of post-treatment hypothyroidism.

177Lu-Labeled Macroaggregated Albumin Imaging and Treatment Effect in Patient with Cystic Thyroid Nodule.

A number of different peptides or antibodies have been labeled with 177Lu and used for clinical imaging and treatment. To our knowledge, 177Lu had never before been used to label macroaggregated albumin, and our radiopharmacy laboratory at Istanbul University-Cerrahpasa made a special effort to do so. We present the case of a 43-y-old man whose cystic thyroid nodule was treated with an intranodular injection of 177Lu-macroaggregated albumin and imaged with SPECT/CT.

Does Radiofrequency Ablation Induce Neoplastic Changes in Benign Thyroid Nodules: A Preliminary Study.

BACKGROUND: To evaluate the clinical feasibility of radiofrequency ablation (RFA) of benign thyroid nodules along with cytomorphological alteration, and any malignant transformation through biopsy. METHODS: The data were retrospectively collected between April 2008 and June 2013 and core needle biopsy (CNB) was performed on 16 benign thyroid nodules previously treated using RFA. The parameters of the patients were compared, between the time of enrollment and the last follow-up examination, using linear mixed model statistical analysis. RESULTS: No atypical cells or neoplastic transformation were detected in the undertreated peripheral portion of treated benign nodules on the CNB specimen. RFA altered neither the thyroid capsule nor the thyroid tissue adjacent to the treated area. On histopathological examinations, we observed 81.2% acellular hyalinization, which was the most common finding. After a mean follow-up period of over 5 years, the mean volume of thyroid nodule had decreased to 6.4±4.2 mL, with a reduction rate of 81.3%±5.8% (P<0.0001). CONCLUSION: RFA is a technically feasible treatment method for benign thyroid nodules, with no carcinogenic effect or tissue damage of the normal thyroid tissue adjacent to the RFA-treated zone.

Management strategy for nerve damage during radiofrequency ablation of thyroid nodules.

OBJECTIVE: The aim of this study was to introduce a management strategy for nerve damage occurring during radiofrequency ablation (RFA). METHODS: From January 2016 to October 2017, 17 patients who experienced the symptoms of nerve damage during RFA were enrolled in this study. If damage to nerves was suspected during RFA, ablation was stopped immediately, and a cold solution of 5% dextrose was injected directly into the space where the nerves were located until symptoms improved. Patients were followed up after the procedure until symptoms had resolved. The clinical data of patients who received a cold dextrose solution injection for nerve damage were compared with those who did not receive such an injection. RESULTS: Of 17 patients who experienced nerve damage, 12 received an injection of cold dextrose solution shortly after the emergence of symptoms. While resolution of symptoms was seen in all 17 patients, the mean time to recovery was significantly faster in the 12 patients who received treatment with an injection of cold dextrose solution than in those patients who did not receive such a treatment (p value = .041). CONCLUSIONS: In the event of thermal damage to adjacent nerve structures during RFA, the direct injection of a cold dextrose solution is a simple and effective treatment that can result in rapid symptom resolution.

Microwave ablation compared to thyroidectomy to treat benign thyroid nodules.

OBJECTIVE: Benign thyroid nodules occur commonly but only require treatment when symptomatic. Surgical treatment, once routine, has been replaced by newer technologies, such as microwave ablation (MWA). The aim of this study was to assess the efficacy, tolerability and cost of MWA compared to surgery to treat benign thyroid nodules. METHODS: After obtaining ethical approval and informed consent, a prospective trial was conducted with 52 patients who had symptomatic benign thyroid nodules. Patients were randomly assigned to receive MWA or surgical treatment. The volume reduction ratio (VRR), thyroid function, complications, HRQoL, costs and some parameters were compared. RESULTS: MWA reduced mean nodule volume by 72.3% at 3 months, 84.5% at 6 months and 92.4% at 12 months as effective as surgery in inactivating nodules, and thyroid dysfunction did not occur during 12-month follow-up for those receiving MWA. Although both MWA and surgery were safe, patients undergoing MWA had fewer cases of complications and rarely reported pain. The MWA group was superior to the surgery group in length of stay, postoperative scar length and the operation time. Compared to patients who underwent surgery, those who underwent MWA had better general health and mental health scores at 6 months and 12 months. The mean total cost of the MWA group was lower than that of the surgery group. CONCLUSION: MWA can significantly reduce nodule volume and nodule-related symptoms with more rapid recovery, more pleasing esthetic outcomes, less physiologic disruption and less expense compared to the surgery.

Sonographic measurement of thyroid nodule changes after microwave ablation: relationship between multiple parameters.

OBJECTIVE: Microwave ablation (MWA) is an effective technique for the treatment of benign thyroid nodules. The aim of this study was to investigate whether it is necessary to study changes in variables other than the volume reduction between follow-up intervals. This study also introduced the index R (Ssurface/V) to explore whether it could reflect features of shape between follow-up intervals. MATERIALS AND METHODS: A total of 236 complex benign thyroid nodules in 230 patients who underwent MWA in our department from October 2013 to February 2017 were included. The Dmax, volume (V), volume reduction ratio (VRR) and index R (Ssurface/V) parameters were evaluated before treatment and postoperatively at 1, 3, 6 and >12 months. Multiple comparisons of these parameters were performed between the baseline and each follow-up period for the entire patient group and subgroups based on diameter and volume. RESULTS: All of the thyroid nodules underwent a significant decrease in size after MWA. The mean decrease in the volume of the thyroid nodules was from 17.40 ± 22.52 mL to 1.31 ± 2.71 mL, with a mean percent decrease of 0.90 ± 0.15% after 12 months. Index R increased over time from 2.55 ± 1.08 to 8.10 ± 5.01, which increased the effectiveness of shape parameterisation between the follow-up periods after the three-month time point, regardless of the initial volume size. For the nodules with a baseline Dmax ≤ 3.4 cm, the V, VRR and index R demonstrated similar capabilities in the evaluation of efficiency before the six-month follow-up visit. CONCLUSIONS: Long-term follow-up emphasises changes in the shape and spatial structure of complex benign thyroid nodules, rather than size variations, after effective MWA. Index R, which is the surface area to volume ratio, can also reflect the shape change to some degree.

Ultrasound-guided microwave ablation in the treatment of benign thyroid nodules in 435 patients.

The objective of the present study was to investigate the effectiveness and safety of ultrasound-guided microwave ablation in the treatment of benign thyroid nodules. A total of 474 benign thyroid nodules in 435 patients who underwent ultrasound-guided microwave ablation from September 2012 to August 2015 were included. Nodule volume and thyroid function were measured before treatment and at 1, 3, 6, and 12 months and subsequently after every 6 months. The nodule volume reduction rate and changes of thyroid function were evaluated. The volume of all thyroid nodules significantly decreased after ultrasound-guided microwave ablation. The average volume was 13.07 ± 0.95 ml before treatment, and 1.14 ± 0.26 ml at 12-months follow-up. The mean volume reduction rate was 90% and the final volume reduction rate was 94%. The volume reduction rate of mainly cystic nodules was significantly higher than that of simple solid and mainly solid nodules (all P < 0.05). The pretreatment volume of nodules was positively correlated with the final volume reduction rate at final follow-up ( P = 0.004). No serious complications were observed after treatment. In conclusion, ultrasound-guided microwave ablation is an effective and safe technique for treatment of benign thyroid nodules, and has the potential for clinical applications. Impact statement Ultrasound-guided MWA is an effective and safe technique for the treatment of benign thyroid nodules. It can significantly reduce the nodule volume, improve the patients' clinical symptoms, has less complication, guarantees quick recovery, meets patients' aesthetic needs, and shows less interference on the physiological and psychological aspects of the body. MWA should be a good complement to traditional open surgery and has potentials in clinical applications.

Incidental Thyroid Nodule Noted on Intra-arterial Hepatic MAA Scan Before 90Y-SIRT.

We report a case of a 61-year-old man who had recurrent hepatocellular carcinoma admitted for series evaluation before Y selective internal radiotherapy (SIRT). Intra-arterial hepatic Tc macroaggregated albumin scan before Y-SIRT revealed a 2.7-cm incidental low-density thyroid nodule with hot uptake. TcO4 scan revealed corresponding hot uptake in the thyroid nodule with near background uptake of normal thyroid tissue, favored autonomous nodule. After Y-microsphere SIRT, bremstrallung imaging revealed no Y-microsphere deposition to thyroid.

Laser, radiofrequency, and ethanol ablation for the management of thyroid nodules.

PURPOSE OF REVIEW: The majority of benign thyroid nodules are nearly asymptomatic, remain stable in size, and do not require treatment. However, a minority of patients with growing nodules may complain of local symptoms or have cosmetic concerns, and thus seek surgical consultation. RECENT FINDINGS: The timely use of ultrasound-guided minimally invasive procedures can change the natural history of benign enlarging thyroid nodules. The procedures produce persistent shrinkage of thyroid nodules and are associated with improvement of local symptoms. Among the various procedures, percutaneous ethanol injection represents the first-line treatment for relapsing thyroid cysts. In solid nonfunctioning nodules, laser and radiofrequency ablation produces a more than 50% reduction in nodular volume that remains persistent over several years. For hyperfunctioning nodules, thermal ablation techniques are not appropriate unless radioactive iodine is contraindicated or not accessible. SUMMARY: MITs are best suited for the management of medium or large-sized nodules that are sonographically well visualized. Conversely, large nodules or nodular goiters that extend into the chest are difficult to treat. MITs are performed in outpatient clinics, are less expensive, and have a lower risk of complications, compared to surgery, and usually do not induce thyroid dysfunction. However, malignancy should be ruled out with a dedicated ultrasound neck assessment and repeat fine needle aspiration of the lesion before treatment.

Restricting ultrasound thyroid fine needle aspiration biopsy by nodule size: which tumors are we missing? A population-based study.

Clinicians use nodule size to determine which thyroid nodules should receive cytological evaluation. The American Thyroid Association (ATA) has recommended against cytological evaluation for nodules <1 cm. It is unknown, however, if nodule size can accurately discriminate lesions that will represent tumors with favorable versus unfavorable prognosis. Also, the characteristics of thyroid cancers that would not be diagnosed if a strict 1 cm size cut off is used as the threshold for biopsy of intrathyroidal nodules are not well established. Using the Rochester Epidemiology Project, a population-based cohort, we identified all thyroid nodules in Olmsted County residents from 2003-2006. To assess the presence of favorable or unfavorable features for each nodule size cutoff, each patient found to have thyroid cancer was risk-stratified using the ATA risk score, which predicts risk of recurrence and persistent disease. Thyroid cancer cases in which a biopsy was done for factors other than thyroid nodule size or suspicious ultrasound features were excluded. We identified 485 thyroid nodules, 46 (9.5%) harbored thyroid cancer. Of the 46 thyroid cancers, 37 (7.6%) had ATA low risk; 8 (1.6%) had intermediate, and only 1 (0.2%) had an ATA high risk scores. The frequency of thyroid cancer and the distribution of ATA risk scores were similar across tumor sizes. In thyroid nodules of <1 cm, 92 (87%) were benign, while 13 (13%) were malignant (11% ATA low risk, 2% ATA intermediate risk) without extrathyroid extension, aggressive histology, or distant metastasis. For all thyroid cancer patients, no cases of persistent disease were found after a median follow-up of 7 years. In this population-based study, we showed that high risk thyroid cancers are rare; indeed, in this highly selected cohort of patients, the ATA's recommendation to avoid cytologic evaluation in thyroid nodules less than 1 cm would not miss any thyroid cancer with high risk features. However, thyroid nodule size at presentation did not accurately discriminate between tumors with favorable versus unfavorable clinicopathologic features. Thus, if further discrimination is desired, for example, to avoid overdiagnosis, features other than size at presentation need to be evaluated.

Efficacy and Safety of Radiofrequency Ablation Versus Observation for Nonfunctioning Benign Thyroid Nodules: A Randomized Controlled International Collaborative Trial.

BACKGROUND: Percutaneous radiofrequency thermal ablation (RFA) has been reported as an effective tool for the management of benign thyroid nodules (BTN). However, large, randomized controlled trials (RCTs) are lacking. OBJECTIVE: The aims of this study were to assess the volume reduction of BTN after a single RFA performed using the moving-shot technique and to compare the volume reduction obtained in patients treated in two centers with different experience of the moving-shot technique. METHOD: This study was an international prospective RCT. It was carried out at the Mauriziano Hospital (Turin, Italy) and the Asan Medical Center (Seoul, Korea). Eighty patients harboring solid, compressive, nonfunctioning BTN (volume 10-20 mL) were enrolled. Twenty patients in each country were treated by RFA using a 18-Gauge internally cooled electrode (group A); 20 nontreated patients in each country were followed as controls (group B). RESULTS: At six months, BTN volume significantly decreased in group A (15.1±3.1 mL vs. 4.2±2.7 mL; p<0.0001), whereas it remained unchanged in group B (14.4±3.3 mL vs. 15.2±3.5 mL). The baseline volume was larger in the Italian series (16.4±2.5 mL vs. 13.9±3.3 mL, p=0.009). However, at six months, there was no significant difference between the Korean group and the Italian group (3.7±2.9 mL vs. 5.5±2.2 mL). Both cosmetic and compressive symptoms significantly improved (3.6±0.5 vs. 1.7±0.4 and 3.6±1.9 vs. 0.4±0.7, respectively; p<0.001). No side effects occurred. CONCLUSIONS: RFA was effective in reducing the volume of BTN. The outcome was similar in centers with different experience in the moving-shot technique.

A simple and accurate dosimetry protocol to estimate activity for hyperthyroidism treatment.

BACKGROUND: Aim of the study was to evaluate accuracy of different dosimetry protocols in estimating the required 131I activity to treat hyperthyroid patients. MATERIALS AND METHODS: Forty consecutive patients were analysed: twenty-eight Graves' disease; twelve autonomous thyroid nodule (ATN). Maximum-uptake, effective half-time and residence-time were estimated from Radioiodine Uptake Test. Residence-time was estimated using a bi-compartmental model. For 131I activity calculation, algorithms laid down in European Association of Nuclear Medicine (EANM) guidelines, ICRP 53 approach and a mono-exponential formula (ME), were compared with OLINDA/EXM results. RESULTS: Based on EANM guidelines, activities to be administered were 3% higher in Graves' disease (p = 0.001) and 3% higher in ATN (p = 0.046). Calculated activities using ICRP 53 approach were significantly lower compared to OLINDA/EXM: 33% in Graves' disease; 17% in ATN. Activities recommended by ME, were significantly higher: in Graves' disease 20%; 42% in ATN. CONCLUSIONS: Only EANM algorithm predict quite well, compared to OLINDA/EXM, the required activity to treat hyperthyroid patients.