Autonomous Nodules Research Articles

8751 Radiofrequency Thermal Ablation in 32 Patients with Toxic Adenomas with Resolution of Hyperthyroidism in All Cases

Abstract Disclosure: L.G. Amato: None. E.M. Volpi: None. L.D. Volpi: None. P.M. Carani: None. A. Rahal: None. Introduction: In the general population, thyroid nodules are found in 3-7% of individuals on physical examination and in 20-76% on ultrasound. Around 8-10% of benign nodules may present autonomous behavior, being called hot nodules, causing symptoms of hyperthyroidism and being called toxic adenomas (TA). In TAs, autonomous hormone production can be caused by somatic activating mutations of genes regulating thyroid growth and hormone synthesis caused by somatic activating mutations of genes regulating thyroid growth and hormone synthesis. Classically, the proposed treatment for autonomous nodules was surgical resection or radioiodine ablation (RAI). In this context, the prevalence of hypothyroidism after the procedure varies from 2% to 3% following lobectomy, and lower after isthmusectomy in the unique circumstance in which the TA is confined to the thyroid isthmus. A study following 684 patients with TA treated with RAI reported a progressive increase in overt and sub-clinical hypothyroidism. Potential complications following near-total/total thyroidectomy include the risk of permanent hypoparathyroidism (< 2.0%) or recurrent laryngeal nerve injury (RLN) (< 2.0%). A small risk of permanent RLN injury exists with surgery for TA. Following RAI therapy, there have been reports of new-onset Graves Disease (up to 4% prevalence) as well as concern for thyroid malignancy and a very minimal increase in late non thyroid malignancy. Radiofrequency ablation (RFA) has been a precise and effective alternative for the treatment of many benign thyroid nodules over the past ten years, including hot nodules. RFA could preserves normal thyroid function compared to surgery or RAI. Clinical case: We evaluated the effectiveness of a single session of RFA in 32 patients with TA, through hormonal status, achieving normalization of thyroid and volumetric reduction of the nodule. Among the 32 patients included in this study, aged between 25 and 88 years, of these, 31 were women and 1 was a man, all of whom underwent a single RFA procedure (“moving shot” technique associated with hydrodissection). We had a single case of a reversible complication: a patient who had transient vocal cord paralysis, with total reversal. There was a reduction in the volume of all nodules as well as all patients progressed to a state of euthyroidism within 60 days of follow-up. Conclusion: A single session of RFA was effective in treating autonomous nodules, restoring euthyroidism in all patients. Presentation: 6/3/2024

8578 Papillary Thyroid Carcinoma in Autonomous Nodule with Low Risk Characteristics in Adolescent

Abstract Disclosure: A. Aponte Velez: None. M.M. Mangual Garcia: None. Thyroid nodules in children are uncommon but are known to carry a greater risk of malignancy than adult thyroid nodules. Additionally, differentiated thyroid cancer (DTC) in children is more commonly found with extrathyroidal extension and metastases which makes the approach and treatment similar but with important differences. The incidence of DTC in children is increasing, making a personalized evaluation of thyroid nodules in pediatric patients even more valuable. Guidelines recommend evaluation of nodules based on sonographic characteristics rather than size of nodule. However, not having worrisome sonographic characteristics may not be as reassuring as in adult patients. A 13 year old female patient presented with a palpable non tender right sided solid thyroid mass. She had no family history of thyroid cancer or history of irradiation. Thyroid function tests were remarkable for TSH:0.017 and positive thyroid stimulating immunoglobulin. Thyroid Ultrasound findings described heterogenous parenchyma with multiple discrete lesions on right thyroid lobe with a dominant solid isoechoic nodule at upper lobe measuring 2.1 x 3.5 x 1.9cm and a smaller nodule in lower lobe. Thyroid scan demonstrated a large functional hot nodule occupying most of right thyroid lobe with suppression of rest of thyroid parenchyma. Ultrasound guided FNA was performed of this lesion and results were negative for malignancy. Patient underwent total thyroidectomy with pathology report revealing right thyroid nodule encapsulated classical variant of papillary thyroid carcinoma. No lymph node metastases were identified. Non neoplastic thyroid parenchyma revealed chronic lymphocytic thyroiditis. Patient underwent radioiodine therapy with Whole Body Scan post radioiodine therapy demonstrating focal increased radionuclide localization at in region of neck consistent with functional thyroid tissue. There was no evidence of metastatic disease. In children, risk of malignancy is underestimated in ultrasonography and cytology. In this patient, papillary thyroid carcinoma was identified despite being stratified as having low risk of malignancy based on ultrasonography characteristics, hyperfunctioning nodule in scintigraphy study along with negative FNA results. Hyperfunctional nodules are usually reassuring for low risk of malignancy but rarely DTC can be found as in our patient. Guidelines agree that FNA is not recommended in functional nodules as surgical resection is the main therapy in children. However, surgery may be deferred if subclinical hyperthyroidism and low risk sonographic characteristics are present such as in our patient. If surgery had been deferred, based on low risk of malignancy, the risk of progression of disease would have been higher. Prognosis of DTC in children is good but the recurrence rate along with morbidity at such a young age may improve with more studies of DTC in children. Presentation: 6/2/2024

Thermoablation Using Radiofrequency and Microwaves of Autonomous Thyroid Nodules: Our Experience

Significant results have been achieved using ultrasound-guided and ultrasound-assisted ablative techniques, such as Laser Thermal Ablation (LTA), Radiofrequency Ablation (RFA), High-Intensity Focused Ultrasound (HIFU), and Microwave Ablation (MWA). These techniques are ideally suited for the treatment of normally functioning benign thyroid nodes with local compressive symptoms or aesthetic problems. These treatments have been applied to hyperfunctioning “hot” nodes. LTA and RFA are the most commonly used. From January 2021 to July 2023 at our Center, a total of 160 patients with benign thyroid nodules were treated, of which 35 had autonomous nodules [1-4]. Our analysis focused on evaluating the locoregional treatment of the latter. Based on the volume and ultrasound-vascular characteristics, patients were selected for thermoablative treatment with either RFA or MWA (Amica Gen HS - Hospital Service) starting in July 2022. No complications were documented. However, one patient was referred for surgery and 1 patient was re-treated with MWA. In the light of personal experience ultrasound-guided thermal ablation treatment with RFA in patients with a single pretoxic or toxic thyroid nodule with or without associated compressive or aesthetic symptoms has proven to be very effective and satisfactory. The treatment must be preceded by adequate information regarding the advantages and disadvantages of the various procedures and the methods of the treatment session. MWA proved to be more effective than RFA with no functional recovery of the treated nodules even if they were relatively larger in size. We obtained the suspension of thyrostatic therapy with normalization of the TSH level in the third month after treatment.

SAT448 Effects Of Radioactive Iodine Therapy Of Compensated Autonomous Thyroid Nodule After Pharmacological Suppression Of Tsh Secretion

Abstract Disclosure: A. Skoczylas: None. W. Mularczyk: None. M. Zyla: None. E.C. Lubocka: None. A. Kluza: None. A. Partyka: None. A. Golebiowska: None. I. Linkert: None. J. Raniszewska: None. M. Skoczylas: None. P. Piwkowski: None. P. Wozniak: None. D. Jedrzejuk: None. Introduction An autonomous nodule with autonomous function on scintigraphy, usually (but not always) leading to hyperthyroidism are representing by around 5-10% of solitary thyroid nodules. Progressive development is observed from a compensated autonomous nodule (in which TSH is not yet completely suppressed, but accompanied by symptoms suggesting an excess of thyroid hormones - most often of cardiac origin) to overt hyperthyroidism in about 60% in 5 years. The method of choice used in the treatment of a solitary nodule with associated hyperthyroidism is radioactive iodine therapy (I-131). Due to the low TSH concentration, the iodine uptake of the remaining thyroid parenchyma is inhibited, which results in the low risk of an after-treatment hypothyroidism. Objective In patients with autonomous nodules without low TSH level but clinical symptoms, will radioactive iodine therapy be equally effective and the risk of hypothyroidism minimalized if suppression of TSH secretion has been achieved pharmacologically before treatment? Methods There were 20 patients (female, mean age of 61,1) with ultrasound-confirmed goiter and autonomous nodule with partial suppression of surrounding thyroid tissue on scintigraphy (mean iodine uptake 14.1%) and mean TSH concentration was 0.48 (0.1-0.83), who had related to the circulatory and nervous system symptoms. These patients were treated with radioiodine the mean activity 364 MBq (242-600MBq). Radioactive iodine therapy was preceded by a 4-week treatment period with 100 µg/d thyroxine and 20 µg triiodothyroxine for suppression of thyrotropin secretion and subsequent reduction of iodine uptake by the thyroid tissue outside the autonomous area and with 5mg/d bisoprolol to minimize thyrotoxicosis. As a result, suppression of thyrotropin secretion mean TSH 0.049 concentration on the day of treatment was achieved, accompanied with iodine uptake inhibition in the part of the thyroid gland outside the autonomous nodule. Radioactive iodine therapy was conducted under these conditions after one day discontinuation of thyroid hormones. Seven days after I-131treatmet each patient was issued to take thiamazole 5 mg/d for 4 weeks with bisoprolol. Results Clinical symptoms disappeared completely. One year after radioactive iodine therapy the mean TSH concentration was 1.46 (0.8-2.65) in all subjects. In 4 years of observation 85% of patients remained euthyreotic with main TSH of 3,0. The mean volume reduction of the autonomous nodules was 45,6% with a reduction of 21.5% of the remaining thyroid parenchyma. Conclusion Radioactive iodine therapy preceded by pharmacological TSH suppression can be used for radical treatment of patients with autonomous nodules with partial TSH reduction to remain the majority (85%) of these patients euthyreotic for 4 years of observation and to reduce radioiodine activity used for treatment. Presentation: Saturday, June 17, 2023

FRI253 Concurrent Adrenal Insufficiency And Hyperthyroidism In A Breast Cancer Patient Treated With Pembrolizumab Therapy

Abstract Disclosure: A.U. Kulkarni: None. D.T. Patel: None. E.B. Ruby: None. Anti-programmed cell death-1 (Anti-PD1) antibodies (e.g., Pembrolizumab) are immune checkpoint inhibitors that are widely in use for the treatment of many advanced malignancies. This has resulted in various side effects known as irAEs (immune-related adverse events). Endocrine irAEs include hypophysitis, adrenal insufficiency (AI), hypothyroidism, and hyperthyroidism. A 40-yo female with a history of recently diagnosed triple-negative breast cancer, status post chemotherapy, and immunotherapy with Pembrolizumab (last treatment a month prior to presentation) came in with fatigue, weight loss, and persistent vomiting for two weeks. Her initial BP was noted to be 80/50 mmHg, with HR 108bpm. She appeared weak and tired with no other abnormalities on physical exam. The thyroid was normal with no enlargement. Significant labs were creatinine 1.4mg/dL (0.4-1.3mg/dL), corrected calcium 12.8mg/dL, TSH of <0.01mUI/L and fT4 of 4.47ng/dL (0.61-1.12ng/dL) (thyroid tests were previously normal). The patient was admitted to the ICU for hypovolemic shock refractory to IV fluids and endocrinology was consulted for multiple hormonal abnormalities. AKI and hypercalcemia were likely from dehydration as they subsequently resolved with IV fluids. AM cortisol level was low at 0.7ug/dL(3-16ug/dL). The cosyntropin test was positive, confirming AI. ACTH level was <5pg/mL (normal<46pg/mL) indicating a diagnosis of secondary AI, likely from immunotherapy. She was initiated on IV hydrocortisone. MRI brain was obtained to evaluate for hypophysitis which was unremarkable. Further thyroid testing was pursued which showed negative Thyroid peroxidase and anti-thyroglobulin antibodies. Thyroid scan showed a focal hot nodule in the left lobe suspicious for an autonomous nodule. She was started on beta blockers and methimazole with the goal of optimizing her thyroid function prior to her elective mastectomy. Pembrolizumab was discontinued with the plan to re-challenge after surgery. BP stabilized and she was discharged home on hydrocortisone with close outpatient follow-up with Endocrinology and Oncology. The clinical manifestations of Anti-PD1-associated AI are very non-specific and difficult to diagnose as they can be confused with the cancer-related illness itself or chemotherapy. Multiple endocrine abnormalities on initial labs with recent Pembrolizumab therapy in our patient raised suspicion for irAEs. Even though the occurrence of AI from anti-PD1 drugs is extremely rare, being <1%, it can be life-threatening. Very few cases of Anti-PD1-induced thyroid dysfunction have been reported, however further testing in our patient confirmed hyperthyroidism from a toxic thyroid nodule. With the increasing popularity of these drugs, endocrinological complications are on the rise, and we as clinicians need to be vigilant and intervene at an early stage to prevent irreversible and fatal outcomes. Presentation: Friday, June 16, 2023

Clinical Course of Early Postoperative Hypothyroidism Following Thyroid Lobectomy in Pediatrics.

Introduction: Thyroid lobectomy reduces risks of surgical complications and need for levothyroxine (LT4). We aimed at identifying the clinical course and risk factors for postlobectomy hypothyroidism to optimize surgical counseling and management in pediatric patients undergoing lobectomy. Methods: Clinical and biochemical presentations pre- and postlobectomy were retrospectively reviewed for 110 patients who underwent thyroid lobectomy between 2008 and 2020 at the Children's Hospital of Philadelphia. Results: Approximately 28.2% of patients (31/110) developed postlobectomy hypothyroidism defined by an elevated thyrotropin (TSH) level, including 24.5% (27/110) with subclinical hypothyroidism (TSH >4.5 and <10.0 mIU/L) and 3.6% (4/110) with overt hypothyroidism (TSH >10.0 mIU/L). LT4 was initiated in 12.7% (14/110) of cases. Most patients (81.6%; 84/103) recovered euthyroidism within 12 months postlobectomy. When excluding patients with autonomous nodule(s), median preoperative TSH was 1.09 (interquartile range [IQR] = 0.70-1.77) mIU/L and 1.80 (IQR = 1.02-2.68) mIU/L in euthyroid and hypothyroid patients, respectively, with multivariate logistic regression confirming the association between an increased preoperative TSH and postlobectomy hypothyroidism (odds ratio = 1.8 [confidence interval 1.08-3.13], p = 0.024). Of the patients who underwent thyroid lobectomy and developed postoperative hypothyroidism (n = 31), 38.7% (12/31) had a preoperative diagnosis of an autonomously functioning thyroid nodule. Conclusions: Thyroid function should be evaluated postlobectomy to assess the need for LT4. LT4 should be considered if the TSH remains elevated, especially if an upward trend is observed or TSH is >10.0 mIU/L. Suppressed preoperative TSH associated with autonomous nodules is an independent risk factor for postlobectomy hypothyroidism.

Hyperthyroidism in Pregnancy: The Delicate Balance between Too Much or Too Little Antithyroid Drug.

Overt hyperthyroidism (HT) during pregnancy is associated with a risk of maternal–fetal complications. Antithyroid drugs (ATD) have a potential risk for teratogenic effects and fetal–neonatal hypothyroidism. This study evaluated ATD treatment and thyroid function control during pregnancy, and pregnancy outcome in women with HT. Patients and methods: A retrospective analysis of 36 single fetus pregnancies in 29 consecutive women (median age 30.3 ± 4.7 years) with HT diagnosed before or during pregnancy; a control group of 39 healthy euthyroid pregnant women was used. Results: Twenty-six women had Graves’ disease (GD, 33 pregnancies), 1 had a hyperfunctioning autonomous nodule, and 2 had gestational transient thyrotoxicosis (GTT). Methimazole (MMI) was administered in 22 pregnancies (78.5%), Propylthiouracil (PTU) in 2 (7.1%), switch from MMI to PTU in 4 (14.2%), no treatment in 8 pregnancies (3 with subclinical HT, 5 euthyroid with previous GD remission before conception). In the 8 pregnancies of GD patients diagnosed during gestation or shortly before (<6 weeks), i.e., with fetal exposure to uncontrolled HT, there was 1 spontaneous abortion at 5 weeks (3.4% of all ATD-treated pregnancies), and 1 premature delivery at 32 weeks with neonatal death in 24 h (3.4%); 1 child had neonatal hyperthyroidism (3.3% of live children in GD women) and a small atrial sept defect (4% of live children in ATD treated women). In women treated more than 6 months until conception (20 pregnancies): (a) median ATD doses were lower than those in women diagnosed shortly before or during pregnancy; (b) ATD was withdrawn in 40% of pregnancies in trimester (T)1, all on MMI < 10 mg/day (relapse in 14.2%), and in up to 55% in T3; (c) TSH level was below normal in 37%, 35% and 22% of pregnancies in T1, T2 and T3 respectively; FT4 was increased in 5.8% (T1) and subnormal in 11.75% in T2 and T3; (d) no fetal birth defects were recorded; one fetal death due to a true umbilical cord knot was registered. Mean birth weight was similar in both ATD-treated and control groups. Hyperthyroidism relapsed postpartum in 83% of GD patients (at median 3 ± 2.6 months). Conclusion: In hyperthyroid women with long-term ATD treatment before conception, drugs could be withdrawn in T1 in 40% of them, the thyroid function control was better, and pregnancy and fetal complications were rarer, compared to women diagnosed during pregnancy. Frequent serum TSH and FT4 monitoring is needed to maintain optimal thyroid function during pregnancy.

Clinical and functional results of radiofrequency ablation and microwave ablation in patients with benign thyroid nodules.

Objectives:To determine how well ultrasound-guidance percutaneous radiofrequency ablation (RFA) and microwave ablation (MWA) performed for benign symptomatic thyroid nodules in terms of clinical and functional outcomes.Methods:Patients who had a thyroid nodule-linked symptoms acting as dysphagia, cosmetic issues, pain, a foreign body sense, hyperthyroidism secondary to autonomous nodules, or concern of malignancy were involved in the study. The primary was the comparison in symptom scores obtained at 1, 3, and 6 months after RFA and MWA. The volume alterations in nodules and alterations in thyroid gland functions were secondary objectives.Results:This prospective study carried out from November 2014 and January 2017 at the General Surgery Department, Marmara University, Faculty of Medicine, Istanbul, Turkey included a total of 100 nodules (50% MWA, 50% RFA). There were statistically significance in pain scores, dysphagia scores, and foreign body sensation scores at 1, 3, and 6 months after therapy in both ablation groups (p=0.0006, p=00004, p=0.0005). At the same time, there were statistically significant reductions in size and volume of the nodules for RFA and MWA (p=0.0004, p=0.0003). There was no significant difference between the RFA and MWA groups’ cosmetic scoring and volume changes (p=0.68, p=0.43).Conclusions:Alternative therapies for benign symptomatic thyroid nodules include RFA and MWA. The findings of this research revealed that both approaches are safe and effective.

Toxic Thyroid Nodule: To FNA or Not?

Background: ATA guidelines recommend evaluation of hyperthyroidism with radioiodine scan and consideration of FNA for non-toxic nodules with suspicious sonographic features. However, there is no standard evidence-based approach to performing ultrasound in patients with toxic nodules. Recent studies have shown increased rates of thyroid cancer in patients with hyperthyroidism and has been shown to demonstrate aggressive histologic features. Clinical Case: A 41-year-old female presented to primary care provider for annual physical exam, found to have intermittent bigeminy and enlarged thyroid on exam. EKG notable for multiple premature ventricular complexes. Evaluation revealed suppressed TSH <0.01 µIU/mL (0.27-4.20), normal free T4 1.27 ng/dL (0.80-1.80), slightly elevated free T3 4.84 pg/mL (2.57-4.43) and elevated TSI 238% (<122). Methimazole was started for treatment of hyperthyroidism. Thyroid sonogram was ordered for abnormal exam, that showed 2.7 cm TIRADS 4 left thyroid nodule with microcalcifications. I-131 uptake values were 20% and 49% at 4-hours and 24-hours, respectively. Technetium-99M scan showed toxic autonomous nodule in the left thyroid lobe corresponding to the one seen on sonogram. The remainder of the thyroid gland showed heterogeneously suppressed uptake. FNA of the thyroid nodule was done due to the presence of microcalcifications and the cytopathology was suspicious for papillary carcinoma. She underwent total thyroidectomy with central neck dissection involving pre-tracheal and paratracheal lymph nodes (level VI). Pathology showed 1.4 cm papillary carcinoma with lymphovascular space invasion and multifocal papillary microcarcinomas in the left thyroid lobe, 0.2 cm papillary microcarcinoma in right thyroid lobe, metastatic papillary carcinoma in 2 out of 5 lymph nodes, largest metastatic deposit 0.1 cm in the largest dimension with no extra nodal extension. There was also follicular hyperplasia noted consistent with Graves’ disease. Post-operatively, she had thyrogen-stimulated adjuvant RAI treatment, dose 107.4 mCi. Post therapy scan did not show evidence of distant metastases. Conclusion: This case demonstrates the identification of a metastatic papillary thyroid carcinoma based on suspicious ultrasound features requiring total thyroidectomy, central neck dissection and adjunct radioactive iodine in a patient with hyperthyroidism from co-existent toxic thyroid nodule and Graves’ disease.

The value of ultrasonography for the indication of fine-needle aspiration in autonomous thyroid nodules.

The risk of malignancy in autonomous thyroid nodules is considered to be very low in adults and fine-needle aspiration (FNA) is not recommended in these cases; however, some studies contest this. Just as ultrasonography (US) has been used to select nonautonomous nodules with initial benign cytology that deserve FNA repetition, this method may also be useful to select autonomous nodules that are candidates for FNA. In this prospective study, FNA was obtained in 48 adults patients with autonomous solitary nodules >1 cm with suspicious US features (at least two of the following findings: hypoechogenicity, microcalcification, irregular margins, taller than wider shape, predominantly or exclusively central vascularization). Cytology was benign in 28 patients (58.3%). Six patients (12.5%) had nondiagnostic cytology and histology revealed benign nodules in these cases. Cytology was indeterminate in nine other patients (18.5%). Of these, seven were adenomas and two were follicular carcinomas on histology. Finally, cytology suspicious for malignancy or malignant cytology was detected in five patients (10.4%), all of them confirmed histologically to be papillary carcinomas (the follicular variant in three). Thus, the frequency of malignancy was 14.6% (two follicular carcinomas and five papillary carcinomas), 8.3% in nodules with two suspicious findings vs 33.3% in nodules with ≥3 suspicious findings (P = .055). The results suggest that the presence of ultrasonographic findings suspicious for malignancy in autonomous thyroid nodules >1 cm is a criterion for the indication of FNA.

Iodine-rich thermal water in cure and rehabilitation from the perspective of the thyroid gland

Bei einzelnen Schilddrüsenerkrankungen (Immunthyreopathie Morbus Basedow, Immunthyreopathie Hashimoto, Struma mit Autonomie) sollte eine übermäßige Jodzufuhr vermieden werden. Betreffend alimentärer Jodzufuhr gibt es dazu reichliches Informationsmaterial. Kuranwendungen werden zu einem breiten Indikationsspektrum eingesetzt und tragen einen wichtigen Teil zur Therapie gerade chronisch degenerativen Erkrankungen, zur Rehabilitation nach Traumen oder Tumorerkrankungen bei. Eine Jodzufuhr ist auch bei Kuranwendungen mit jodhaltigem Thermalwasser möglich, das Ausmaß der Jodzufuhr ist dabei abhängig von der Applikationsform und der Expositionsdauer. Informationsmaterial dazu ist nur spärlich in der Literatur zu finden. Der Artikel betrachtet jodhaltige Kuranwendungen aus thyreologischer Sicht im Spannungsfeld von positiven und möglichen negativen Auswirkungen einer jodhaltigen Kuranwendung. Neben einem Einblick in die Physiologie und Pathophysiologie des Jodstoffwechsels und Auswirkungen auf einzelne Schilddrüsenerkrankungen wird die Intensität einer Jodaufnahme bei unterschiedlichen Kuranwendungen dargestellt. Eine Übersicht von Kurorten/Thermen mit jodhaltigem Wasser in Österreich und seinen Nachbarstaaten ergänzt von einem Algorithmus zur Selektion von Patienten für eine Kur in Kurorten mit jodhaltigem Wasser wird präsentiert, um mögliche negative jodinduzierte Schilddrüsenfehlfunktionen schon vor Kurantritt zu vermeiden. Dem klinisch tätigen Arzt wird damit eine Unterstützung in der Entscheidungsfindung bei der Auswahl bzw. Ablehnung einer jodhaltigen Kuranwendung für seine Patienten zur Verfügung gestellt.Zusatzmaterial onlineZusätzliche Informationen sind in der Online-Version dieses Artikels (10.1007/s10354-020-00782-x) enthalten.

Management of adenomas and toxic multinodular goiters with Iodine 131

In accordance with all the guidelines of the various international scientific societies, treatment using radioiodine (RAI) of autonomous toxic adenomas and toxic multinodular goiters is highly recommended and its effectiveness its efficacy has now been widely demonstrated and established. RAI treatment is effective to normalise thyroid function, remove functional autonomy and reduce thyroid volume. According to published data on several thousand patients treated with RAI, the success rates ranges between 85% and 100%. Moreover, with more than 70 years of experience, this treatment does not present any particular risk for patients. However, as regards pregnancy, there are no absolute contra-indications to radioiodine treatment. To date, these results include a relatively high rate of hypothyroidism in the long term and approximately one patient out of five treated, will require thyroid hormone substitution. It would be more effective to harmonise and work up on dosimetric personalized models allowing the calculation of the effective dose to be delivered to the autonomous nodule to be treated while preserving the normal thyroid parenchyma in order to optimise the patient's outcome and to favor extensive euthyroidism.

Correction for hyperfunctioning radiation-induced stunning (CHRIS) in benign thyroid diseases.

Radioiodine-131 treatment has been a well-established therapy for benign thyroid diseases for more than 75 years. However, the physiological reasons of the so-called stunning phenomenon, defined as a reduced radioiodine uptake after previous diagnostic radioiodine administration, are still discussed controversially. In a recent study, a significant dependence of thyroid stunning on the pre-therapeutically administered radiation dose could be demonstrated in patients with goiter and multifocal autonomous nodules. A release of thyroid hormones to the blood due to radiation-induced destruction of thyroid follicles leading to a temporarily reduced cell metabolism was postulated as possible reason for this indication-specific stunning effect. Therefore, the aim of this study was to develop dose-dependent correction factors to account for stunning and thereby improve precision of radioiodine treatment in these indications. A retrospective analysis of 313 patients (135 with goiter and 178 with multifocal autonomous nodules), who underwent radioiodine uptake testing and radioiodine treatment, was performed. The previously determined indication-specific values for stunning of 8.2% per Gray in patients with multifocal autonomous nodules and 21% per Gray in patients with goiter were used to modify the Marinelli equation by the calculation of correction factors for hyperfunctioning radiation-induced stunning (CHRIS). Subsequently, the calculation of the required activity of radioiodine-131 to obtain an intra-therapeutic target dose of 150 Gy was re-evaluated in all patients. Furthermore, a calculation of the hypothetically received target dose by using the CHRIS-calculated values was performed and compared with the received target doses. After integrating the previously obtained results for stunning, CHRIS-modified Marinelli equations could be developed for goiter and multifocal autonomous nodules. For patients with goiter, the mean value of administered doses calculated with CHRIS was 149 Gy and did not differ from the calculation with the conventional Marinelli equation of 152 Gy with statistical significance (p = 0.60). However, the statistical comparison revealed a highly significant improvement (p < 0.000001) of the fluctuation range of the results received with CHRIS. Similar results were obtained in the subgroup of patients with multifocal autonomous nodules. The mean value of the administered dose calculated with the conventional Marinelli equation was 131 Gy and therefore significantly below the CHRIS-calculated radiation dose of 150 Gy (p < 0.05). Again, the fluctuation range of the CHRIS-calculated radiation dose in the target volume was significantly improved compared with the conventional Marinelli equation (p < 0.000001). With the presented CHRIS equation it is possible to calculate a required individual stunning-independent radioiodine activity for the first time by only using data from the radioiodine uptake testing. The results of this study deepen our understanding of thyroid stunning in benign thyroid diseases and improve precision of dosimetry in radioiodine-131 therapy of goiter and multifocal autonomous nodules.

Subclinical hyperthyroidism in the course of autonomous nodules - clinical evaluation.

Subclinical hyperthyroidism (SCH), also known as mildly symptomatic hyperthyroidism, has recently been diagnosed more frequently. One of the main endogenous causes of this disorder is autonomously functioning thyroid nodule (AFTN). Despite the fact that it is usually asymptomatic, SCH entails repercussions on the cardiovascular system and bone, and it carries a risk of progression to overt hyperthyroidism with a typical clinical picture. Treatment is still controversial, and its benefits are widely debated in literature. From 459 patients authors selected a group of 49 patients (10.6% of all subjects with hyperthyroidism), 41 women (83.7%) with AFTN at the stage SCH treated in the Outpatient Endocrinological Clinic and the Department of Endocrinology of the Medical University of Lublin over a three-year period. The method applied in the study was a retrospective analysis of medical records with a particular account of medical history, physical examination, and additional tests obtained during the process of diagnostic and therapeutic procedures. Forty-one patients (83.7%) suffered from typical symptoms of hyperthyroidism; only eight patients (16.3%) were asymptomatic. The most frequently reported symptoms were tachycardia in women (51.2%) and anxiety in men (50%). The type of thyrostatic drugs and the length of therapy did not affect the outcome of iodine-131 therapy. In the vast majority of the patients (87.8%) radioidodine therapy was effective; 30 patients (61.2%) reached euthyreosis and 13 patients (22.5%) developed hypothyroidism. Most patients with SCH in the course of AFTN suffered from typical symptoms of overt hyperthyroidism; only every sixth patient was asymptomatic. The volume of autonomous adenomas did not affect the result of 131I therapy; however, the impact of AFTN volume as well as the thyroid volume on RIT efficacy requires futher investigation. In the vast majority of patients 131I therapy was an effective method of treatment, and an earlier therapeutic effect was observed more often in the patients with focal lesions located in the right lobe.

Outcome of Fixed Dose Radioiodine Therapy in Hyperthyroid Patients –Three Years Follow up Study at INMAS Mitford

Background: Hyperthyroidism is a morbid condition. Radioiodine therapy is very safe, popular and effective treatment of hyperthyroidism. This study was design to determine the outcome of fixed dose radioiodine (RAI) therapy in hyperthyroid patients in a single institute.&#x0D; Patients and Methods: This was a retrospective study conducted from January 2014 to December 2016 at 1Institute of Nuclear Medicine and Allied Sciences, Sir Salimullah Medical College Campus, Mitford, Dhaka. A total 71 patients were enrolled for this study. All the patients were pretreated with antithyroid drugs than underwent fixed dose of RAI therapy. They were followed up at regular interval. Chi-square and paired t test was done to see the level of significance.&#x0D; Results: Mean age of the patients were 41.61 years (range 19-60 years). Male were 29 (40.8%) and female were 42 (59.2%). Mean months of pretreated with antithyroid drugs were 30.59 ± 23.68 months, range (2-96 months). Before RAI therapy mean TSH was 0.12 ± 0.14 μ IU/ml range (0.0001-0.54 μIU/ml) and after RAI therapy mean TSH was 1.6 ±1.5μ IU/ml range (0.002-5.00 μIU/ml). Before RAI therapy mean FT4 was 26.26 ±10.25 fmol/ml, range (7.86-47.78 fmol/ml ) and after RAI therapy mean FT4 was 23.45±8.22 fmol/ml, range (8.78-40.45 fmol/ml). All patients diveided into three groups: Graves’ disease (29), toxic multinodular goiter ( 28) and toxic autonomous nodule (14). After three years of follow up 27 (38%) patients were euthyroid, 2 (2.8%) remain hyperthyroid, 3(4.2%) were relapse cases and 39 (54.9%) were hypothyroid.&#x0D; Conclusion: This follow up study showed that patients treated with RAI therapy became hypothyroid in the long run. Relapse and persistent hyperthyroid state were very common phenomenon after RAI therapy.&#x0D; Bangladesh J. Nuclear Med. 21(1): 8-11, January 2018

Study of Thyroid Abnormalities using Scintigraphy

Radionuclide imaging is an integral part of functional evaluation of thyroid diseases. This study aimed to study thyroid abnormalities using scintigraphy, The study population consisted of 173(149 female and 24 male) patients with thyroid abnormalities, and referred to Nuclear Medicine, Fujairah hospital for thyroid scintigraphy during the period from Jan 10, 2016 to June 30 , 2018 . All patients Thyroid function test were done before coming to radiology department. The mean age of patients was 38 years. The results of this study revealed that thyroid nuclear medicine scan findings as normal in 6.4 % (16 patients) and abnormal in 91% (157 patients) , Autonomous Nodule 2 (1.1),nodular goiter- NTG , TNG 30 (17.3%),Goiter11(6.4%),Grave disease13(7.5%), Multinodular goiter 43(24.8%), Thyroiditis 20 (11), Thyroid nodule 2 (1.1), Toxic multinodular goiter 21 ,Toxic goiter 15 (8.7%), Normal 16 (9.2%). This study concluded that radionuclide methods are complementary and provide information that can help in the appropriate management of various thyroid diseases.

Fine-needle aspiration in all thyroid incidentalomas at 18 F-FDG PET/CT: Can EU-TIRADS revise the dogma?

Focal thyroid incidentalomas (TIs) are observed in 2% of 18 F-FDG PET/CT representing malignancy in one-third of cases. Currently, due to the lack of evidence on their optimal management, guidelines suggest fine-needle aspiration cytology (FNAC). The study aim was to evaluate the role of ultrasound evaluation according to EU-TIRADS to assess the risk of TIs and inform FNAC prescriptions. We retrospectively reviewed 18 F-FDG PET/CT TIs recorded during the period 2014-2017. Enrolled were TIs with histological outcome and autonomous nodules. Cases with uncertain matching between 18 F-FDG PET/CT, ultrasound and histology were excluded. According to the selection criteria, 75 TIs, being 13 (17.3%) malignant and 62 (82.7%) benign, were included. Cancers had significantly higher SUVmax and SUVmax ratio (Mann-Whitney P<0.01) than benign, and the most accurate cut-offs were >7.1 and >3.65, respectively. At ultrasound, the cancer rate was 0% in EU-TIRADS 2, 2.9% in EU-TIRADS 3, 4.2% in EU-TIRADS 4% and 78.6% in EU-TIRADS 5 (chi-squared P<0.001). Sensitivity, specificity, PPV, NPV and accuracy for malignancy were 92%, 64%, 35%, 98% and 69% for SUVmax; 85%, 68%, 36%, 96% and 71% for SUVmax ratio; and 85%, 95%, 79%, 97% and 93% for EU-TIRADS, respectively. The absence of all these three features reached a specificity of 97.1%. EU-TIRADS, within a clinical careful approach, can discriminate with significant accuracy lesions at high risk of malignancy from those at low risk among TIs at 18 F-FDG PET/CT. Additionally, a centre-based threshold for SUV parameters should be useful for the initial assessment of these lesions during PET/CT reading and reporting.

Features and Outcome of Autonomous Thyroid Nodules in Children: 31 Consecutive Patients Seen at a Single Center

Most thyroid nodules are benign and their accurate identification can avoid unnecessary procedures. In adult patients, documentation of nodule autonomy is accepted as reassurance of benign histology and as justification to forgo biopsy or thyroidectomy. In contrast, the negative predictive value of nodule autonomy in children is uncertain. Some recent publications recommend surgical resection as initial management, but few address the degree of TSH suppression or the specific scintigraphic criteria used to diagnose autonomy. The objective of the study was to study the presenting features and cancer risk of children with autonomous nodules. Medical records of all 31 children diagnosed with autonomous nodules at our center from 2003 to 2014 were retrospectively reviewed. All children met full diagnostic criteria for autonomous nodules, defined by both autonomous 123I uptake into the nodule and the suppression of uptake in the normal thyroid parenchyma on scintigraphy performed during hypothyrotropinemia. The median age of presentation was 15 years (range 3-18 y) with a female to male ratio of 15:1. Fifty-eight percent of patients had solitary nodules and 42% had multiple nodules. The median size of each patient's largest autonomous nodule was 39 mm (range 18-67 mm). Most of the children in this series (68%) had diagnostic biopsies and/or operative pathology of their largest autonomous nodule, which showed benign cytology or histology in all cases. In this pediatric series, the cancer rate observed in biopsied or resected autonomous nodules was 0%. Whereas larger studies are needed to confirm our findings, these results agree with earlier reports suggesting that thyroid cancer is rare in rigorously defined autonomous nodules and support that conservative management may be offered to selected children who meet strict diagnostic criteria for autonomous nodules, deferring definitive therapies until adulthood when the risks of thyroidectomy and 131I ablation are lower.

Abstract #1169: 80 Year Old Woman with Thyroid Cancer that Originates in an Autonomous Toxic Nodule Pretreated Radioiodine

Abstract #1169: 80 Year Old Woman with Thyroid Cancer that Originates in an Autonomous Toxic Nodule Pretreated Radioiodine

Incidentally recognised thyroid focal uptake of 99mTc-sestamibi during stress myocardial perfusion scintigraphy.

99mTc-sestamibi, a radiopharmaceutical widely used in the assessment of myocardial perfusion, can be used as an indicator of thyroid disease due to its oncophilic character. The aim of this study was to establish the usefulness of performing additional examinations of radiotracer uptake in the thyroid gland during standard stress scintigraphy with sestamibi in order to identify thyroid diseases. After a retrospective evaluation of 330 consecutive myocardial perfusion scintigraphies performed in our hospital during one year, 41 patients with a focal accumulation of 99mTc-sestamibi in the thyroid were enrolled in the study. The patients underwent clinical examinations, including thyroid ultrasonography and TSH, fT4, fT3, aTPO, TRAB, calcitonin, and CEA levels. Based on the thyroid ultrasounds, 21 patients were referred for fine-needle aspiration biopsy of the thyroid. An abnormal accumulation of radiotracer in the thyroid was found in 41(12.4%) of 330 patients who underwent stress cardiac scintigraphy. Thirteen (31.7%) of those patients had multinodular euthyroid goitres, 12 (29.2%) had a single thyroid nodule (including two autonomous nodules), 11 (26.8%) had autoimmune thyroid disease, and one (2.4%) had papillary thyroid carcinoma. In 12 (29.2%) with thyroid tracer uptake there was no thyroid pathology. Additional evaluation of radiotracer uptake in the thyroid during standard myocardial perfusion scintigraphy is a valuable tool in the detection of thyroid diseases. The additional or parallel evaluation of radiotracer uptake in the thyroid should be considered during every myocardial scintigraphy.