Dose Of Radioactive Iodine Research Articles

Cure rates after a single dose of radioactive iodine to treat hyperthyroidism

Cure rates after a single dose of radioactive iodine to treat hyperthyroidism

SAT469 Risk Factors for Relapse in Graves’ Disease and the Clinical Outcomes of Radioactive Iodine Treatment in Relapsed Cases

Abstract Disclosure: L. WingChing: None. X. Khor: None. F. Carter: None. Q. Ashcroft: None. V. Chandrabalan: None. P. M Joseph: None. Authors: Li Wing Ching, Xiao Ying Khor, Frederick Carter, Ashcroft Quinta, Vishnu Chandrabalan, Joseph Pappachan. Background: Relapse of Graves’ disease occurs in ≈50% of cases after the antithyroid pharmacotherapy. Identifying risk factors associated with relapse is crucial for planning treatment including radioactive iodine (RAI) ablation as well as to inform patients of probable clinical outcome following such treatment. Aims: (1) To identify the factors associated with relapse of Graves’ disease when the condition is first diagnosed. (2) To characterise the clinical outcomes and re-relapse rates after RAI treatment. Methods: Retrospective study of patients treated for Graves’ disease (with positive TSH-receptor antibodies [TRAb] >1.0 IU/L) between April 2004 and May 2021 at Lancashire Teaching Hospitals NHS Trust, UK. Demographic, clinical, laboratory, and treatment data were retrieved from prospectively maintained electronic health records. Data retrieved included known factors associated with high risk of relapse including markedly raised thyroid hormone (Free T4 [FT4] and/or Free T3 [FT3]), and TRAb levels. Outcome data after treatment was also analysed including the effects of RAI therapy such as hypothyroidism and time to its development, failure rate of first dose of RAI and its management. Results: Out of 1450 patients with Graves’ disease, 188 cases with meaningful study data receiving RAI ablation during the study period were analysed. The following factors (median (interquartile range/IQR) of relapsed vs non-relapsed) were associated with relapse requiring RAI ablation: TRAb levels - 10.3 (4.8-20.9) vs 5.1 (2.0-12.4) IU/L; p<0.001, FT4 - 56.7 (39.3 - 73.0) vs 42.6 (30.9-62.4) pmol/L; p<0.01, and FT3 - 24.4 (13.8 - 33.6) vs 16.2 (10.8-26.5) pmol/L; p=0.03. The median age at RAI ablation therapy was 48 (IQR 39-57.3) years with a female preponderance (140 [74.5%] cases). Radioactive Iodine-131 (131I) 555 MBq was used for treatment in all cases. 172 (91.5%) cases developed post-RAI hypothyroidism at a median follow up period of 3 (IQR: 2-11) months. RAI ablation failure occurred in 20 (10.6%) cases of whom 12 (60%) cases were successfully managed by RAI re-ablation, 5 (25%) cases preferred antithyroid pharmacotherapy, one (5%) underwent subtotal thyroidectomy and 2 (10%) cases refused treatment. Conclusions: Graves’ disease cases with high median levels of TRAb ≥10.3 IU/L, FT4 ≥56.7 pmol/L and/or FT3 ≥24.4 pmol/L at initial presentation are at high risk of relapse. RAI ablation should be offered to such patients as first-line treatment at initial presentation of the disease. Hypothyroidism occurs after RAI ablation in ≈92%. Chance of treatment failure with first RAI ablation procedure is only ≈11%. Presentation Date: Saturday, June 17, 2023

THU681 Change In The Clinicopathological Characteristics And Outcomes Of Pediatric Thyroid Carcinoma In Korea: Focusing On Data From A Tertiary Hospital In Korea

Abstract Disclosure: J. Yoo: None. D. Leem: None. H. Ryu: None. H. Park: None. J. Kim: None. Y. Oh: None. T. Kim: None. S. Kim: None. J.H. Chung: None. Introduction: The incidence of thyroid carcinoma in adults in Korea increased until 2012, but has declined rapidly since then. However, the incidence of pediatric thyroid carcinoma increased until 2013, decreased slightly, and then increased again. Changes in the clinicopathological characteristics of pediatric thyroid carcinoma over time have not yet been elucidated. In this study, we aimed to evaluate the changes in the clinicopathological characteristics and outcomes of pediatric thyroid carcinoma from 1995 to 2022. Subjects and Methods: A total of 170 patients under the age of 19 years who were diagnosed with differentiated thyroid carcinoma at tertiary hospital in Seoul, Korea were enrolled. The patients were divided into four groups based on the year of initial surgery: 1995 – 2005 (n = 33), 2006 – 2010 (n = 46), 2011 – 2015 (n = 57), and 2016 – 2022 (n = 34). Results: The age at diagnosis, gender, primary tumor size, T stage, N stage, and M stage did not significantly differ among the four groups. Also, there was no significant difference over time in the route of detection (symptomatic vs. asymptomatic; P for trend = 0.519). The incidence of diffuse sclerosing variant of papillary thyroid carcinoma tended to increase over time (P=0.06). Surgical extent (P for trend = 0.001) and cumulative radioactive iodine (RAI) dose (P for trend < 0.001) significantly decreased over time. Nevertheless, the disease-free survival among the four groups did not change during the median follow-up 115.5 (62.3 – 155.3) months (log-rank P = 0.451). Conclusions: Although the overall incidence of pediatric thyroid carcinoma is gradually increasing in Korea, surgical extent and cumulative RAI dose significantly decreased and the clinicopathological characteristics and the disease-free survival did not change over time. Presentation: Thursday, June 15, 2023

THU661 Marine-Lenhart Syndrome: An Unusual Presentation Of Hyperthyroid Disease

Abstract Disclosure: B. Ji: None. O. Adeniran: None. L. Soni: None. Background: Marine-Lenhart syndrome, also known as nodular Graves’ disease, is defined as the coexistence of functioning thyroid nodules and Graves’ disease. It is a rare syndrome, with a prevalence of approximately 0.8-2.7%. The two diseases may coexist or present at different times [1]. Treatment options include high doses of antithyroid medications or radioactive iodine and thyroidectomy in selected cases [2]. Clinical Case: A 72-year-old female with a medical history of right-sided breast cancer treated with lumpectomy and radiation therapy in 2012 on anastrozole was referred for multinodular goiter (MNG) evaluation in 2018. She was clinically and biochemically euthyroid. Her thyroid ultrasound demonstrated two isoechoic right lobe nodules measuring 2.1cm and 1.3cm, respectively. An isoechoic rounded isthmus nodule measures 2.1cm. Three isoechoic nodules in the left lobe measuring 2.6cm, 2.2cm, and 1.7cm. She underwent fine needle aspiration (FNA) of two nodules in 2019, and both demonstrated benign follicular nodules with Bethesda II classification. At a follow-up visit in 2021, she reported unintentional weight loss but denied any other symptoms of hyperthyroidism, including heat intolerance, palpitation, tremor, or diarrhea. Physical examination was significant for exophthalmos, lid retraction, and diffusely enlarged thyroid with non-tenderness to palpation. Thyroid function tests revealed subclinical hyperthyroidism with TSH of <0.01uIU/mL (0.27-4.2uIU/ml) and FT4 of 1.5ng/dL(0.9-1.8ng/mL). Thyroid stimulating immunoglobulin (TSI) was 3.98IU/L (0.00-0.55IU/L), and TSH receptor antibody was 7.64 IU/L (0.00-1.75 IU/L). She was started on low-dose methimazole therapy. Thyroid uptake scan showed markedly elevated radioactive iodine uptake with 63.46% in 24 hours and focal nodular regions of increased uptake of the bilateral thyroid lobes compatible with toxic multinodular goiter. Repeated thyroid ultrasound in 2022 revealed stable-sized nodules with at least two new sub-centimeter nodules in both lobes. The patient was also seen by ophthalmology and plans to start teprotumumab treatment. At her most recent follow-up visit in January 2023, she has been continued on methimazole 2.5mg daily. Conclusion: The criteria for diagnosing Marine-Lenhart syndrome have not been well established. The possibility of Marine-Lenhart syndrome should be considered in hyperthyroid patients with positive antibodies and nodular goiter. In this case, she was initially asymptomatic with an enlarged multinodular goiter; three years later, she developed subclinical hyperthyroidism due to Graves’ disease and toxic multinodular goiter. Her symptom and thyroid function are well-controlled with low-dose methimazole. Presentation: Thursday, June 15, 2023

SAT559 Challenges Involved in Managing a Paraplegic Patient with Metastatic Papillary Thyroid Cancer Requiring Radioactive Iodine Therapy

Abstract Disclosure: G. Al-Naqeeb: None. E. Munger: None. P. Veeraraghavan: None. C. Cochran: None. P. Bernaldez: None. P. Wong: None. N. Devaraj: None. T. Fisher: None. K. Lee: None. O. Owoade: None. I. Jones: None. S. Gubbi: None. J. Klubo-Gwiezdzinska: None. Background: High radioactive iodine (RAI) therapy doses utilized for treating thyroid cancer patients require a 24-48-hour radiation isolation period until the total effective dose equivalent exposure (TEDE) to the general population does not exceed 5mSv. We present a unique scenario of a paraplegic patient with metastatic papillary thyroid cancer (PTC) requiring RAI therapy and the radiation precaution strategies implemented by our team to reduce radiation exposure risk to the medical staff.A 69-year-old female with RAI-refractory tall cell-variant PTC (pT4aN1bM1; BRAF V600E pathogenic variant) with pulmonary metastases, paraplegia due to a motor vehicle accident with neurogenic bowel and bladder, was referred to our center for management of PTC. Laboratory data revealed a serum thyroglobulin of 2313 ng/mL (normal=1.6-59.9), and anatomical imaging showed numerous pulmonary nodules that had increased in size and number compared to prior imaging from 6 months ago. Due to disease progression, re-differentiation therapy with dabrafenib was initiated. After 3-months of dabrafenib therapy, a diagnostic thyroid hormone withdrawal-aided 131I scan with dosimetry revealed a significant re-induction of RAI uptake in pulmonary lesions and it was determined that therapy with an RAI dose of 200 mCi would not exceed a safe radiation exposure to the bone marrow of 200 rads. A multi-step mitigation strategy was developed based on a multidisciplinary team meeting and appropriate mock sessions. Stay times were estimated for individuals based on historical TEDE following the care of non-paralyzed patients receiving similarly prescribed activity. To minimize exposure to nursing staff, the patient’s Foley catheter was shielded with lead lining and bowels were emptied the night before RAI with a laxative. For each entry, posted safety sheets were updated with one-foot and one-meter isodose lines and on-contact exposure rates. Two nurses and one radiation safety staff member donned full personal protective equipment (PPE; full body suit, double gloves, booties, face covering) in the staging area and entered via lane one. While nursing provided direct care needs, radiation safety staff emptied the shielded catheter, organized clutter and packaged radioactive waste containers. Upon completion of duties, staff exited via lane two, removed PPE, and performed a full personnel contamination survey in the staging area. The patient successfully underwent RAI therapy with 200 mCi. Six months later the serum thyroglobulin had reduced to 48.4ng/ml with a substantial reduction in pulmonary metastatic tumor burden on imaging studies. Conclusion: Post-RAI therapy care of paralyzed patients during radiation isolation poses a unique challenge to medical staff warranting modifications in routine care practices, which can be achieved safely through optimal planning and enhanced training. Presentation Date: Saturday, June 17, 2023

SAT520 Efficacy of Radioactive Iodine Redifferentiation Therapy in Previously Iodine Refractory Differentiated Thyroid Cancers

Abstract Disclosure: D. Toro-Tobon: None. J.C. Morris: None. C. Hilger: None. C.S. Peskey: None. D.M. Jolanta: None. M.M. Ryder: None. Objective: Patients with metastatic differentiated thyroid cancer (DTC) that are radioactive iodine (RAI) refractory (RAIR) have a poor prognosis. Redifferentiation therapy (RDT) has emerged as a potential approach to restore RAI avidity in this disease. The aim of this study was to examine the efficacy and predictors of RAI restoration in RAIR disease, as well as examine the outcomes of patients re-treated with high dose RAI following RDT. Methods: A retrospective review was conducted of 33 patients with RECIST-progressive metastatic RAIR-DTC who underwent RDT between 2017 and 2022 at the Mayo Clinic. All patients underwent genomic profiling, and either MEK inhibitor alone or combination BRAF-MEK inhibitors were prescribed for 4 weeks. At week 3, Thyrogen-stimulated I-123 whole body scans were performed. Those with increased RAI avidity in metastatic foci received high dose I-131 therapy using a previously published modified dosimetry protocol. Baseline and clinicopathologic outcomes were comprehensively reviewed. Results: Of the 33 patients, 12 of 23 (52%) with papillary thyroid cancers (PTC), 4 of 4 (100%) with follicular variant PTCs (FV-PTC), and 7 of 7 (100%) with follicular thyroid cancers (FTC) had restored RAI avidity following RDT using dabrafenib/trametinib (7 for BRAF mutant disease) or trametinib monotherapy (12 for RAS mutant disease). All 11 (100%) RAS mutant tumors (2 PTC, 3 FV-PTC, and 6 FTC) had RAI avidity restoration compared to 7 (36%) with BRAF mutant disease (6 PTC, and 1 FV-PTC). Of the 19 patients (57%) with restored RAI avidity (responders), 18 (94%) received I-131 with a median dose of 294 mCi. The median thyroglobulin (Tg) in responders was 294 mIU/L as compared to 29 mIU/L in non-responders. Following RDT-facilitated I-131 treatment, 94.7% achieved RECIST defined objective response (complete or partial response, stable disease, non-complete response/non-progressive disease) with a median progression free survival of 18 months and an overall survival of 30 months. Overall, patients with FTC (p=0.01), RAS mutation (p<0.001), Tg of 294 mIU/L or more (p=0.03), largest tumor diameter of 1.7 cm or less (p=0.05), bone metastasis (p=0.007), and without locoregional nodal disease (p=0.04), were more likely to demonstrate restored RAI avidity following RDT. Of the entire cohort, 2 (6%) patients experienced histologic transformation to anaplastic thyroid cancer and 5 (15%) patients died, all had had RAI restoration and received high-dose RAI following RDT. Conclusion: RDT has the potential to restore RAI avidity and induce RECIST responses following I-131 therapy in select patients with RAIR-DTC, particularly those with RAS mutations and ‘follicular’ phenotypes. Further studies are needed to better characterize the long-term survival and/or safety outcomes of high-dose RAI following RDT, particularly whether it could be associated with histologic transformation. Presentation Date: Saturday, June 17, 2023

Lymph node ratio independently associated with postoperative thyroglobulin levels in papillary thyroid cancer

ObjectivesTo investigate the impact of the lymph node ratio (LNR) on postoperative thyroglobulin (Tg) levels in patients with papillary thyroid carcinoma (PTC). Patients and MethodsThis was a retrospective, cohort study. The association between clinicopathological variables and postoperative unstimulated Tg (uTg) levels, preablative-stimulated Tg (sTg) levels, and postablative unstimulated Tg levels was analysed. ResultsA total of 300 patients with PTC were identified. Multivariate logistic analysis showed that M classification (odds ratio [OR], 2.33; 95% confidence interval [CI], 1.62–3.34), and postoperative thyroid-stimulating hormone levels (OR, 1.01; 95% CI, 1.01–1.02) were independently associated with postoperative uTg levels. One hundred and sixteen patients underwent radioactive iodine (RAI) therapy. Multivariate analysis showed that LNR in the central neck (OR, 1.24; 95% CI, 1.02–1.51), LNR in the lateral neck (OR, 1.73; 95% CI, 1.09–2.77), RAI dose (OR, 1.43; 95% CI, 1.21–1.69), and M classification (OR, 1.79; 95% CI, 1.22–2.61) were independently associated with preablative sTg levels. Tumour size (OR, 1.01; 95% CI, 1.00–1.01), LNR in the central neck (OR, 1.28; 95% CI, 1.08–1.51), LNR in the lateral neck (OR, 1.66; 95% CI, 1.10–2.49), RAI dose (OR, 1.54; 95% CI, 1.34–1.79), and M classification (OR, 1.56; 95% CI, 1.12–2.19) were also independently associated with postablative uTg levels. ConclusionLNR was independently associated with postoperative Tg levels in patients with PTC. Patients with high LNR were more likely to have incomplete biochemical responses after surgery.

Predictive value of insulin marker before and after recovery of Grave’s disease patients

Introduction and Aim: Grave’s disease is a disease of the thyroid glands. Early diagnosis of hyperthyroidism can improve treatment and control. This study examined hyperthyroidism-related insulin hormone alterations before and after radioactive iodine 131 treatment. This study also examined how the medical condition affected these indicators. Materials and Methods: The participants in this study included 50 people who were diagnosed with Grave’s disease, as well as 23 healthy individuals as controls. Direct inquiry was used as the technique for gathering demographic information from the patients who participated in the study. The thyroid stimulating and insulin hormonal levels of each patient were recorded before and after undergoing a hypothyroidism treatment regimen of three months that consisted of a dose of radioactive iodine 131 ranging from 10 to 20 mci. Results: This research indicated a significant relation to exist between age and insulin levels among patients diagnosed with Grave’s disease. In addition, the research also demonstrated a significant association between levels of thyroid-stimulating hormone (TSH) and insulin hormones in patients both before and after radiation therapy. Conclusion: Insulin hormonal levels could be used as a predictor of the severity of hyperthyroidism.

The effect of age on the severity of dry mouth occurring in patients receiving high dose radioactive iodine treatment

Aims: Dry mouth of individuals causes many oral discomforts and undesirable conditions. In order to prevent such an undesirable situation from occurring, it is aimed to complete the Radioactive Iodine Therapy (RAI) treatment with less damage by mastering all possible factors. In our study, we aimed to find the level of the effect of the age factor.
 Methods: In this study, we included patients who received high-dose radioactive iodine treatment after total thyroidectomy for differentiated thyroid cancer and were hospitalized in our clinic. These patients were selected among the patients who applied to our hospital between 2021-2022. We specifically focused on patients who reported dry mouth and obtained salivary gland scintigraphies of their submandibular glands. Afterwards, we looked at the ratio of the age of the patients with the level of dry mouth. We analyzed the collected data using statistical methods.
 Results: The data analysis was performed using the Chi-square (χ2) test and the Spearman correlation test to examine the relationship between age and the severity of dry mouth in patients undergoing high-dose RAI treatment for thyroid cancer. Our hypotheses were two-sided, and statistical significance was considered at p-values ≤0.05. The results of our analysis revealed that there was no significant direct correlation between age and the severity of dry mouth in the patients. This suggests that age is not a determining factor for the occurrence or severity of dry mouth in individuals receiving high-dose RAI treatment.
 Conclusion: In our study, it was concluded that the age factor alone was not a determining factor in terms of the severity of dry mouth. Therefore, it is important to consider additional factors and potential underlying causes when evaluating and managing dry mouth in patients receiving high-dose RAI therapy for thyroid cancer.

Evaluating the effectiveness of a fixed little dose of radioactive iodine (I131) in treatment for Graves’ disease

Radioiodine (I131) therapy is a clinically established method for hyperthyroidism treatment. The most suitable dose for successful treatment is still controversial since it is affected by several factors. Thus, there are two techniques for proper dose adjustment; Fixed and calculated.This study aims to evaluate the response difference of hyperthyroidism to a low fixed dose of 5 mCi (185 MBq) in comparison with other fixed doses of 10 mCi and 15 mCi (370 and 555 MBq) radioactive iodine treatment protocols. It also aims to raise the possibility of euthyroid state after successful ablation with such a low fixed dose rather than hypothyroid results and long-life replacement therapy.A prospective study of 100 patients were clinically and scintigraphically diagnosed with Graves' disease (GD) from the endocrinology department at King Faisal Medical Complex. The kind and size of the patient's thyroid were determined before treatment and then randomized into three groups, based on the administrated radioactive iodine dose, (5 mCi, Group I), (10 mCi, Group II) and (15 mCi, Group III). The thyroid function tests were performed after 3 and 6 months, as a follow-up, for the assessment of the outcome.Similar responses for fixed doses of 5, 10 and 15 mCi were determined, with no significant difference between the three study groups. Successful ablation was achieved in 23 (71.9%), 27 (84.4%) and 22 (71.0%) patients in the 5, 10, 15 mCi groups respectively without a significant difference between the groups with p-value of 0.695. Moreover, all considered related factors to the outcomes show no effect except the thyroid size with a p-value <0.001. The baseline size of the thyroid gland was significantly smaller in the Successful ablation group and the Euthyroidism group as compared to the Hyperthyroidism group (51.36 ± 4.32 and 53.73 ± 5.19 vs. 70.54 ± 8.70; p < 0.001).Fixed little doses of 5, 10 or 15 mCi of I131 show comparable remission rates. These outcomes were not affected by any factor related to the thyroid except thyroid size. Larger thyroid glands have less chance of remission. So, we envisage that a 5 mCi of radioactive iodine dose is recommended as a routine treatment for patients diagnosed with GD.

Comparison of bilateral axillo-breast approach robotic thyroidectomy and open thyroidectomy for papillary thyroid carcinoma.

For papillary thyroid carcinoma (PTC) surgery requiring total thyroidectomy and central lymph node dissection, it is controversial whether the bilateral axillo-breast approach robotic thyroidectomy (BABA RT) can replace the open thyroidectomy (OT). To evaluate the efficacy of two surgical approaches. Relevant literatures were searched from PubMed, EMBASE and Cochrane Library. Studies comparing two surgical approaches and meeting the inclusion criteria were selected. Compared with OT, BABA RT showed a similar incidence of postoperative complications, including recurrent laryngeal nerve palsy, hypocalcemia, hypoparathyroidism, bleeding, chyle leakage and incision infection, as well as number of retrieved central lymph nodes and postoperative total dose of radioactive iodine. However, BABA RT involved longer operative time (weighted mean difference [WMD] 72.62, 95% confidence interval [CI] 48.15-97.10, P < .00001) and higher postoperative stimulated thyroglobulin level ([WMD] 0.12, 95% [CI] 0.05-0.19, P = .0006). The efficacy of BABA RT is basically similar to OT in this meta-analysis, but the higher postoperative stimulated thyroglobulin level attracts our attention. Longer operative time requires us to shorten. Randomized clinical trials with large samples and longer follow-up data are still essential to further demonstrate the value of the BABA RT.

Factors Affecting Ablation Success After I-131 Radioactive Iodine Therapy in Low and Intermediate Risk Papillary Thyroid Cancer.

The study was to evaluate the effect of radioactive iodine (RAI) treatment application time and clinical, histopathological factors on ablation success in patients with operated papillary thyroid cancer (PTC) in low and intermediate-risk. One hundred sixty-one patients with PTC in the low and intermediate-risk were evaluated. Most patients (89.4%) were in the low-risk, and 10.6% were in the intermediate-risk. When the patients were divided into two groups according to the date of receiving RAI treatment after surgery, those who received early treatment (≤3 months) constituted the majority of the patients (72.7%). Seventeen patients received 1.85 Gigabecquerel (GBq), 119 3.7 GBq, 25 5.55 GBq RAI. Most patients (82%) achieved ablation success after the first RAI treatment. The time interval between surgery and RAI treatment did not affect ablation success. Stimulated Tg level measured on the RAI treatment day was an independent predictive factor for successful ablation (p<0.001). The cut-off value of Tg found to predict ablation failure was 5.86 ng/ml. It was concluded that 5.55 GBq RAI treatment could predict ablation success compared to 1.85 GBq dose (p=0.017). It was concluded that having a T1 tumor may predict treatment success compared to a T2 or T3 tumor (p=0.001, p<0.001, retrospectively). The time interval does not affect ablation success in low and intermediate-risk PTC. The ablation success rate may decrease in patients who receive low-dose RAI and have high Tg levels before treatment. The most crucial factor in achieving ablation success is giving enough doses of RAI to ablate the residual tissue.

Intermediate-risk Differentiated Thyroid Cancer with Stimulated Thyroglobulin or N1b Needs High Adjuvant Radioactive Iodine Dose

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Correlation between metabolic uptake of F-18-FDG-PET/computed tomography and thyroglobulin level in differentiated thyroid cancer patients with suspected recurrence.

Our objective is to determine if there is correlation between serum thyroglobulin and SUVmax of the main lesion detected in F18-FDG-PET/CT scan, in differentiated thyroid cancer (DTC) patients with suspected recurrence. All DTC patients enrolled in this prospective study, received at least one dose of radioactive iodine. During follow-up, they are suspected to have a recurrence due to elevated tumor markers although negative iodine whole-body scans. For all patients, F18-FDG-PET/CT scanning was performed. A 3D volume of interest was generated over the liver and main lesion to obtain maximum standardized uptake value (SUVmax). We calculated the lesion/liver ratio. Follow-up and/or histopathological examination were the gold standard. Pearson's correlation coefficient was calculated between thyroglobulin and SUVmax of the main lesion. Sixty-eight patients were recruited in this study. F18-FDG-PET/CT identified suspicious malignant lesions in 42 patients, equivocal in 18 patients, while 8 patients showed no abnormal findings. Fifty-two, 6, 8, and 2 patients were true positive, true negative, false positive, and false negative respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 72%, 57% 87%, 35%, and 69% respectively. The median SUVmax and lesion/liver ratio were significantly higher in the malignant lesions than that of benign lesions (3.9 vs. 1.3 and 1.45 vs. 0.54 respectively). We found that the main lesion SUVmax and lesion/liver ratio have a positive moderate correlation with thyroglobulin (0.338 and 0.325 respectively). In DTC patients with suspected recurrence, SUVmax of F18-FDG-PET/CT lesion showed a moderate positive correlation with serum thyroglobulin.

Risk of Second Primary Malignancy Associated with Cumulative Doses of Radioactive Iodine in Patients with Differentiated Thyroid Cancer

Clinical ThyroidologyVol. 35, No. 4 Thyroid CancerRisk of Second Primary Malignancy Associated with Cumulative Doses of Radioactive Iodine in Patients with Differentiated Thyroid CancerDavid Toro-Tobon and Omar EI KawkgiDavid Toro-Tobon Division of Endocrinology, Diabetes, Metabolism and Nutrition, Department of Medicine, Mayo Clinic, Rochester, Minnesota, U.S.A.Search for more papers by this author and Omar EI Kawkgi Division of Endocrinology, Diabetes, Metabolism and Nutrition, Department of Medicine, Mayo Clinic, Rochester, Minnesota, U.S.A. Department of Endocrinology, Mayo Clinic Health System, Eau Claire, Wisconsin, U.S.A.Search for more papers by this authorPublished Online:11 Apr 2023https://doi.org/10.1089/ct.2023;35.154-156AboutSectionsView articleView Full TextPDF/EPUB Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail View articleFiguresReferencesRelatedDetails Volume 35Issue 4Apr 2023 Information© Copyright 2023, Mary Ann Liebert, Inc.To cite this article:David Toro-Tobon and Omar EI Kawkgi.Risk of Second Primary Malignancy Associated with Cumulative Doses of Radioactive Iodine in Patients with Differentiated Thyroid Cancer.Clinical Thyroidology.Apr 2023.154-156.http://doi.org/10.1089/ct.2023;35.154-156Published in Volume: 35 Issue 4: April 11, 2023PDF download

Inflammatory biomarkers predict outcomes of patients with radioactive iodine refractory thyroid cancer treated with sorafenib.

The objective of this multicenter, retrospective cohort study was to evaluate the ability of inflammatory biomarkers representing the host immune system to predict outcomes in 70 patients with progressive radioactive iodine (RAI)-refractory thyroid cancer who were treated with sorafenib. Patients were divided into low and high inflammatory biomarker groups based on median values. Progression-free survival (PFS) and overall survival (OS) were assessed based on the lymphocyte-to-monocyte ratio (LMR), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR). The median LMR, NLR, and PLR values were 3.4, 2.2, and 140.1, respectively. No significant differences were observed in baseline characteristics of high and low LMR, NLR and PLR groups. Median PFS values were 6.6 and 19.5 months in the low and high LMR groups, respectively (P < 0.001). Compared with the high NLR and PLR groups, PFS was significantly prolonged in the low NLR and PLR groups (P = 0.003 and P = 0.041 respectively). In the multivariate analysis, low LMR and high NLR were associated with poor PFS after adjusting for multiple confounding factors including age, sex, pathology, disease-related symptoms, serum thyroglobulin level, lung-only metastasis, cumulative RAI dose, time from diagnosis, and longer diameter of the target lesion (hazard ratio, HR = 2.42; 95% confidence interval, CI 1.25-4.71; P = 0.009, and HR = 2.09; CI, 1.06-4.14; P = 0.033, respectively). High LMR, low NLR, and low PLR were significantly associated with prolonged OS (P = 0.011, P = 0.023, and P = 0.007, respectively). Patients with at least one risk factors for inflammatory biomarkers presented a significantly lower PFS (HR 2.29; CI, 1.36-3.84; P = 0.003) and OS (HR 2.95; CI, 1.49-5.81; P = 0.006) than patients without any risk factor. Baseline inflammatory biomarkers successfully predicted PFS and OS in patients with progressive RAI-refractory thyroid cancer treated with sorafenib. These prognostic biomarkers might help arrive at appropriate clinical decisions regarding the use of sorafenib.

Linear association between radioactive iodine dose and second primary malignancy risk in thyroid cancer.

We aimed to investigate whether the risk of second primary malignancy (SPM) in patients with thyroid cancer (TC) receiving radioactive iodine (RAI) therapy rises in a cumulative, dose-dependent manner compared with those not undergoing RAI. Using the Korean National Health Insurance Service National Health Information Database (2002-2019), we investigated hazard ratios of SPM associated with RAI in TC. SPM was defined as a second primary malignancy diagnosed at least 1 year after TC diagnosis. Of 217 777 patients with TC (177 385 women and 40 392 men; mean [SD] age, 47.2 [11.6] years), 100 448 (46.1%) received RAI therapy. The median (IQR) follow-up duration was 7.7 (5.5-10.3) years, and the median (IQR) cumulative RAI dose was 3.7 (1.9-5.6) GBq. From 2004 to 2019, SPM incidence rates were 7.30 and 6.56 per 1000 person-years in the RAI and non-RAI groups, respectively, with an unadjusted hazard ratio of 1.09 (95% confidence interval = 1.05 to 1.13); this rate remained at 1.08 (95% confidence interval = 1.04 to 1.13) after adjustment for multiple clinical confounding factors. Notably, SPM risk increased significantly, from 3.7 GBq with full adjustments, and a strong linear association between cumulative RAI dose and SPM was observed in the restricted cubic spline analysis. Regarding cancer subtypes, myeloid leukemia and salivary gland, trachea, lung and bronchus, uterus, and prostate cancers were the most significantly elevated risks in patients who underwent RAI therapy. This study identified that SPM risk increased linearly in a dose-dependent manner in patients with TC undergoing RAI therapy compared with those not undergoing RAI therapy.

Review: Improving quality of life in patients with differentiated thyroid cancer.

Well differentiated thyroid cancer is a common malignancy diagnosed in young patients. The prognosis tends to be excellent, so years of survivorship is expected with low risk disease. When making treatment decisions, physicians should consider long-term quality of life outcomes when guiding patients. The implications for treating indolent, slow growing tumors are immense and warrant careful consideration for the functioning years ahead. Surgery is the standard of care for most patients, however for a subset of patients, active surveillance is appropriate. For those wishing to treat their cancer in a more active way, novel remote access approaches have emerged to avoid a cervical incision. In the era of "doing less", options have further expanded to include minimally invasive approaches, such as radiofrequency ablation that avoids an incision, time off work, a general anesthetic, and the possibility of post-treatment hypothyroidism. In this narrative review, we examine the health related quality of life effects that surgery has on patients with thyroid cancer, including some of the newer innovations that have been developed to address patient concerns. We also review the impact that less aggressive treatment has on patient care and overall wellbeing in terms of active surveillance, reduced doses of radioactive iodine (RAI) treatment, or minimally invasive techniques such as radiofrequency ablation (RFA) for low risk thyroid disease.

Transient facial nerve paralysis following low dose radioactive iodine in a patient with Graves' disease.

Transient facial nerve paralysis following low dose radioactive iodine in a patient with Graves' disease.

Can we consider downsizing the radioiodine therapy dose in some patients of differentiated cancer thyroid with multiple skeletal metastasis on diagnostic iodine-131 whole-body scan with single-photon emission computed tomography-computed tomography?

ABSTRACT It has been found that around 30% of patients of differentiated thyroid cancer with skeletal metastasis alone showed complete remission. Laboratory studies have explained a mechanism of bone metastasis where in the first premetastatic niches are formed, leading on to the formation of micrometastasis, and then on to overt metastasis. In view of the above, identifying patients who are at the micrometastatic stage can help establish a separate category of patients who would require a lower dose of radioactive iodine than those with overt metastasis. A diagnostic iodine-131 whole-body scan with single-photon emission computed tomography-computed tomography can help in identifying this category of patients.