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Objective: To develop and validate a radiomics-clinical combined model combining preoperative computed tomography (CT) and clinical data from patients with papillary thyroid carcinoma (PTC) to predict the efficacy of initial postoperative 131I treatment., Methods: A total of 181 patients with PTC who received total thyroidectomy and initial 131I treatment were divided into training and testing sets (7:3 ratio). Univariate analysis and multivariate logistic regression were used to screen clinical factors affecting the therapeutic response to 131I treatment and construct a clinical model. Radiomics features extracted from preoperative CT images of PTCs were dimensionally reduced through recursive feature elimination and least absolute shrinkage and selection operator. Logistic regression was used to establish a radiomics model, and a radiomics-clinical combined model was developed by integrating the clinical model. The area under the curve (AUC), sensitivity, and specificity were used to evaluate the prediction performance of each model., Results: Multivariate analysis revealed that pre-131I treatment serum thyroglobulin was an independent clinical risk factor affecting the efficacy of initial 131I treatment (P = .002), and the AUC, sensitivity, and specificity for predicting the efficacy of initial 131I treatment were 0.895, 0.899, and 0.816, respectively. After dimensionality reduction, 14 key CT radiomics features of PTCs were included. The established radiomics model predicted the efficacy of 131I treatment in the training and testing sets with AUCs of 0.825 and 0.809, sensitivities of 0.828 and 0.636, and specificities of 0.745 and 0.944, respectively. The combined model improved the AUC, sensitivity, and specificity in both sets., Conclusion: The preoperative CT-based radiomics model can effectively predict the efficacy of initial postoperative 131I treatment in patients with intermediate- or high-risk PTC, and the radiomics-clinical combined model exhibits better predictive performance., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society.)

Context: Risk factors for radioactive iodine (RAI)-refractory disease in follicular (FTC) and oncocytic thyroid carcinoma (OTC) are unknown., Objective: The aim of this study is to identify clinical and histopathological risk factors for RAI-refractory disease in FTC and OTC patients, facilitated by an extensive histopathological revision., Methods: All adult FTC and OTC patients treated at Erasmus MC (the Netherlands) between 2000 and 2016 were retrospectively included. The 2015 American Thyroid Association guidelines were used to define RAI-refractory disease. An extensive histopathological revision was performed applying the 2022 World Health Organization Classification using PALGA, the Dutch Pathology Databank. Logistic regression was used to identify risk factors for RAI-refractory disease, stratified by histological subtype., Results: Ninety FTC and 52 OTC patients were included, of whom 14 FTC (15.6%) and 22 OTC (42.3%) patients developed RAI-refractory disease over a follow-up time of 8.5 years. RAI-refractory disease occurred in OTC after fewer cycles than in FTC (2.0 [interquartile range (IQR): 1.0-2.0] vs 2.5 [IQR: 2.0-3.75]), and it substantially decreased 10-year disease-specific survival, especially in OTC (46.4%; FTC 85.7%). In FTC, risk factors were higher age at diagnosis, pT3/pT4 stage, N1 stage, widely invasive tumors, and extrathyroidal extension. N1 stage and M1 stage were the strongest risk factors in OTC, rather than histopathological characteristics of the primary tumor., Conclusion: To our knowledge, this is the first study that correlates clinical and histopathological risk factors with RAI-refractory disease in FTC and OTC, facilitated by a histopathological revision. In FTC, risk factors for RAI-refractory disease were foremost histopathological characteristics of the primary tumor, whereas in OTC presentation with lymph node and distant metastasis was associated with RAI-refractory disease. Our data can help clinical decision-making, particularly in patients at risk for RAI-refractory disease., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society.)

Differentiated thyroid carcinoma is the most common endocrinological malignancy with an increasing incidence over the last 30 years, with women being more frequently affected. In indicated cases, total thyroidectomy followed by adjuvant radioiodine administration is performed, despite current trends towards less aggressive treatment. We would like to investigate the possible adverse effects of radioiodine (RAI) on ovarian function using a simple serum biomarker. Anti-Müllerian hormone (AMH) appears to be the best endocrine marker for assessing physiological age-related oocyte loss for healthy women. The aim of our ongoing prospective study is to determine serum AMH to estimate ovarian reserve for premenopausal women treated with RAI. Over the course of one year, 33 serum samples from women with thyroid cancer and 3 serum samples from healthy women were examined. AMH levels were compared before radioiodine treatment and at regular intervals after treatment. Mean of the AMH level was 5.4 ng/ml (n=33) prior to RAI. The average level of AMH decreased to 1.8 ng/ml in 4-6 months after treatment. In 22.2 % of patients AMH dropped to 0 ng/ml from a non-zero value. Thereafter, we observed an increase in AMH, the average value was 2.7 ng/ml in 8-12 months. We demonstrated a significant decrease in AMH shortly after radioiodine treatment and a subsequent trend of increase at one year after treatment. Consequently, predicting the adverse effects of radioiodine by assessing a serum biomarker could help to select an appropriate treatment strategy for young women planning pregnancy.

Accurate postoperative assessment is critical for optimizing 131 I therapy in patients with papillary thyroid cancer (PTC). This study aimed to develop a pathology model utilizing postoperative digital pathology slides to predict lymph node and/or distant metastases on post-therapeutic 131 I scan after initial 131 I treatment in PTC patients. A retrospective analysis was conducted on 229 PTC patients who underwent total or near-total thyroidectomy and subsequent 131 I treatment after levothyroxine (LT4) withdrawal between January 2022 and August 2023. The pathology model was developed through two stages: patch-level prediction and WSI-level prediction. The clinical model was constructed using statistically significant variables identified from univariate and multivariate logistic regression analysis. Of the 229 patients, 19.6% (45/229) exhibited 131 I-avid metastatic foci in post-therapeutic 131 I scan. Multifactorial analysis identified stimulated thyroglobulin (sTg) as the sole independent risk factor. The AUC of the pathology model in the training and test cohorts were 0.976 (95% CI 0.948-1.000) and 0.805 (95% CI 0.660-0.951), respectively, which were significantly higher than the clinical model (AUC 0.652 and 0.548, Pall < 0.05). This model has the potential to serve as a valuable tool for clinicians in tailoring treatment strategies, thereby optimizing therapeutic outcomes for PTC patients., (© 2024. The Author(s).)

Importance: Radioactive iodine (131I or RAI) therapy has long been the standard of care for most patients with differentiated thyroid cancer (DTC) after primary surgery. However, no multicenter prospective studies have identified the optimal administered activity and stimulation method for RAI therapy in patients with intermediate-risk DTC., Objective: To compare the efficacy and safety of recombinant human thyrotropin (SNA001) with thyroid hormone withdrawal (THW) plus 3.7 GBq RAI in patients with intermediate-risk DTC., Design, Setting, and Participants: This noninferiority, open-label, phase 3 randomized clinical trial was conducted at 19 sites in China from April 16, 2020, to September 9, 2021, with a follow-up period of 8 months. Patients aged 18 to 70 years with DTC who had undergone a total or near-total thyroidectomy and had no distant metastasis were enrolled in the trial. Statistical analysis followed the full analysis and per-protocol analysis sets and was performed between November 18, 2021, and April 18, 2022., Intervention: Patients were randomly assigned 1:1 to receive SNA001, 0.9 mg, intramuscular injection daily for 2 days or to undergo thyroid hormone withdrawal for 3 to 6 weeks., Main Outcomes and Measures: The primary end point was the success rate after 6 to 8 months of RAI therapy. Success was defined as a negative diagnostic whole-body scan result and a stimulated thyroglobulin level less than 1.0 ng/mL., Results: A total of 307 patients (192 females [62.5%]; median [range] age, 40 [19-69] years) were randomized: 154 to the SNA001 group and 153 to the THW group. Baseline characteristics were evenly matched between the 2 groups. Noninferiority in the success rate of RAI therapy between groups was met, with success rates of 43.8% in the SNA001 group and 47.1% in the THW group (risk difference, -3.3; 95% CI, -14.8 to 8.3 percentage points). Forty-six patients (29.9%) in the SNA001 group reported adverse events compared with 90 (58.8%) in the THW group during RAI therapy (P < .001). No treatment-related adverse events leading to discontinuation and drug modification occurred in the SNA001 group., Conclusions and Relevance: This randomized clinical trial showed that SNA001 was noninferior to THW plus 3.7 GBq RAI in patients with predominantly intermediate-risk DTC. SNA001 also demonstrated a favorable safety profile compared with THW and had a lower incidence of adverse events., Trial Registration: Chinese Clinical Trial Registry Identifier: ChiCTR2100046907.

Radioiodine (RAI) therapy after surgery, is an important component for the treatment of patients with papillary thyroid cancer (PTC), the most common thyroid cancer. In this study we sought to evaluate the cancer-specific survival (CSS) impact of RAI in specific thyroid cancer subgroups. The Surveillance, Epidemiology, and End Results (SEER) database were used to identify patients with PTC who underwent surgery between 2000 and 2019. Patients not treated with RAI were compared to those treated with RAI using propensity score matching (PSM) on the basis of identical inclusion criteria. A total of 106 333 patients were identified from the SEER database. RAI therapy was associated with improved CSS in the matched cohort (HR: 0.83; 95% CI: 0.72-0.96, p=0.01) but not in the unmatched data set (HR: 1.46; 95% CI: 1.30-1.64, p<0.001) among all PTC patients regardless of disease stage. Detailed analyses, however, showed that only patients with high-risk disease (pT3N1, pT4N1) experienced the greatest benefit in CSS. In the lower disease stages, no significant differences were recognized in the group of PTC patients with or without RAI therapy. One exception: in the group of PTC patients in stage pT1bN0, a significant difference was seen towards RAI. This is, however, most likely due to the large number of patients investigated. In summary, RAI therapy should not be used in low-risk PTC patients and might be used to some extent in intermediate-risk PTC patients. The histological suptype of the tumor needs to be considered in this context., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Objective: Ablation therapy is employed in low-risk differentiated thyroid cancer (DTC) cases to facilitate patient monitoring by reducing thyroglobulin (Tg) levels to measurable levels below after surgery by eliminating residual thyroid tissue. However, there is still uncertainty about the minimum activity dose required for effective ablation. Opting for low-dose [131I]-NaI for ablation offers several advantages for both patients and healthcare services. Particularly in this tumor group with a high life expectancy (approximately 90-95 % at 10 years), [131I]-NaI treatment should not pose a risk to the patient's post-treatment life and should not compromise their quality of life. However, there is a need for a well-defined identification of factors predicting successful ablation., Methods: Clinical data, laboratory findings, and imaging tests of 287 patients with low-dose 1110 MBq (30 mCi) [131I]-NaI ablation therapy for DTC were retrospectively reviewed. Post-ablation imaging and laboratory findings categorized ablation success/failure. The successful ablation group was determined according to the excellent response criteria outlined in ATA criteria. Relationships between clinical, pathological findings, biochemical common variables, and treatment failure were analyzed., Results: An excellent response was achieved in 77% of the entire group according to ATA criteria post-ablation. Male gender and high Tg levels on the day of ablation (Tg cut-off: 10 ng/mL and 5.35 ng/mL) were associated with unsuccessful ablation., Conclusions: Our results indicate that a 1110MBq (30mCi) ablation dose is sufficient to achieve an excellent response in most low-risk DTC cases 6-12 months later. When selecting the dose for ablation, besides the histological markers mentioned in guidelines and age, we observed that stimulated Tg values and gender may be important in predicting ablation success., (Copyright © 2024 Sociedad Española de Medicina Nuclear e Imagen Molecular. Published by Elsevier España, S.L.U. All rights reserved.)

Background: The 2015 American Thyroid Association (ATA) guidelines proposed the use of the ATA Risk Stratification System and American Joint Committee on Cancer Tumor-Node-Metastasis (AJCC/TNM) Staging System for postoperative radioiodine decision-making. However, the management of patients with intermediate-risk differentiated thyroid carcinoma (DTC) is not well defined. In this study, we aimed to evaluate the therapeutic efficacy of radioactive iodine therapy (RAIT) among various subgroups of patients with intermediate-risk DTC after surgery., Methods: This was a retrospective study based on the Surveillance, Epidemiology, and End Results (SEER) database (2010-2015). The DTC patients with intermediate risk of recurrence were divided into two groups (treated or not treated with radioactive iodine (RAI)). As the treatment was not randomly assigned, stabilized inverse probability treatment weighting (sIPTW) was used to reduce selection bias. We used the Kaplan-Meier method and log-rank test to analyze overall survival (OS) and cancer-specific survival (CSS)., Results: Kaplan-Meier analysis after sIPTW found a significant difference in OS and CSS between no RAIT and RAIT (log-rank test, P < 0.0001; P = 0.0019, respectively). The Kaplan-Meier curves of CSS in age cutoff of 55 years showed a significant association between no RAIT and RAIT (log-rank test, P = 0.0045). Univariate and multivariate Cox regression showed RAIT was associated with a reduced risk of mortality compared with no RAIT (hazard ratio [HR] 0.59, 95% confidence interval [95% CI 0.44-0.80]). Age (≥ 55) years showed a worse CSS regardless of whether or not a patient was treated or not treated with RAI ([HR] 8.91, 95% confidence interval [95% CI 6.19-12.84])., Conclusions: RAIT improves OS and CSS in patients with intermediate-risk DTC after surgery. 55 years is a more appropriate prognostic age cutoff for the relevant classification systems and is a crucial consideration in RAI decision-making. Therefore, we need individualized treatment plans., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: Thyroid lobectomy (TL) is an appropriate treatment for up to 4 cm intrathyroidal differentiated thyroid cancer (DTC). There is scarce data regarding TL outside first-world centers. Our aim is to report a cohort of patients with DTC treated with TL in Chile., Methods: We included DTC patients treated with TL, followed for at least 6 months, characterized their clinicopathological features and classified their risk of recurrence and response to treatment., Results: Eighty-two patients followed for a median of 2.3 years (0.5-7.0). Seventy-three (89%) patients had papillary, 8 (9.8%) follicular and 1 (1.2%) high-grade DTC. The risk of recurrence was low in 56 (68.3%) and intermediate in 26 (31.7%). Eight (9.8%) patients required early completion thyroidectomy and radioiodine. At last follow-up, 52 (70.3%) had excellent, 19 (25.7%) had indeterminate, and 1 (1.4%) had structural incomplete response., Conclusion: In a developing country, TL is an adequate option for appropriately selected DTC patients., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Differentiated thyroid cancers (DTCs) constitute the primary histological subtype within thyroid cancer. Due to DTCs' distinctive radioiodine (RAI) uptake mechanism, standard treatment involving surgery, with or without adjunctive therapy using RAI and levothyroxine inhibition, typically yields favorable prognoses for the majority of patients with DTCs. However, this favorable outcome does not extend to individuals with decreased RAI uptake, termed radioiodine-refractory thyroid cancers (RAI-RTCs). Recent research has revealed that the genetic mutations and gene rearrangements affecting sites such as RTKs , RAS, BRAF and TERTp lead to structural and functional abnormalities in encoded proteins. These abnormalities aberrantly activate signaling pathways like the mitogen-activated protein kinase (MAPK) and phosphatidylinositol-3-hydroxykinase (PI3K) signaling pathways, resulting in thyroid cells dedifferentiation, sodium/iodide symporter (NIS) dysfunction, and consequent the RAI-refractory nature of DTCs. Targeted therapy tailored to mutations presents a promising avenue for the treatment of RAI-RTCs. Lenvatinib and sorafenib, multi-kinase inhibitors, represent the standard first-line systemic treatment options, while cabozantinib is the standard second-line treatment option, for this purpose. Furthermore, ongoing clinical trials are exploring selective kinase inhibitors, immune checkpoint inhibitors, and combination therapies. Notably, numerous clinical trials have demonstrated that selective kinase inhibitors like BRAF, MEK and mTOR inhibitors can restore RAI uptake in tumor cells. However, further validation through multicenter, large-sample, double-blinded randomized controlled trials are essential. Enhanced treatment strategies and innovative therapies are expected to benefit a broader spectrum of patients as these advancements progress., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Chen, Yao, Tan and Li.)

Background: The optimal cumulative activity (CA) of I-131 therapy for patients with metastatic differentiated thyroid cancer (mDTC) remains contentious. This study aimed to determine the maximum CA of I-131 that could be administered without a significant increase in adverse events (AEs) by analyzing a long-term cohort of patients., Methods: Data from patients with mDTC treated with I-131 therapy and followed for at least 2 years from 1967 to 2019 were reviewed. Patients were categorized into 3 groups based on the received CA: group A (≤600 mCi), group B (>600-1000 mCi), and group C (>1000 mCi). The study assessed long-term AEs and survival outcomes., Results: The study included 671 adult patients with mDTC (mean age, 48 years; range, 19-81) with a median follow-up of 122 months (interquartile range: 82-180). Group A, group B, and group C comprised 269 (40.0%), 212 (31.6%), and 190 (28.4%) patients, respectively. Ten-year survival rates were 72%, 42.7%, and 29% in groups A, B, and C, respectively. A total of 40/671 (6%) AEs were observed in 38 patients: 3 (1.1%), 12 (5.7%), and 25 (13.2%) in groups A, B, and C, respectively. Five patients developed second primary malignancy: 3 in group A and 1 each in group B and C. However, CA >1000 mCi of I-131 was associated with significant increase in bone marrow suppression, decreased pulmonary function, and xerostomia (P < .001)., Conclusion: The study suggests that a maximum CA of up to 1000 mCi strikes a favorable balance between keeping AEs low and benefiting a subset of patients with extensive metastases showing intense I-131 concentration., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Purpose: Papillary thyroid cancer (PTC) is the most common thyroid malignancy, characterized by its slow progression and favorable prognosis. This study re-evaluates the efficacy of radioactive iodine (RAI) therapy versus no RAI in low-risk PTC patients following total thyroidectomy., Methods: A retrospective analysis was conducted on 588 patients treated between 2010 and 2016 at a major tertiary center in Turkey. Patients were divided into two cohorts: those receiving total thyroidectomy (TT) with high-dose RAI (100 mCi) and those receiving TT alone. A matched cohort of 138 patients per group was analyzed to minimize bias., Results: Follow-up data indicated that at 24 months, the RAI group demonstrated a higher percentage of excellent treatment responses (86%) compared to the non-RAI group (74%). Long-term follow-up showed that 99.3% of the RAI group achieved no evidence of disease (NED), versus 90.6% in the non-RAI group. Recurrence rates were significantly lower in the RAI group (1%) compared to the non-RAI group (5.8% with a > 2.0 ng/ml cut-off for biological events)., Conclusion: In summary, the findings from this study underscore the efficacy of RAI therapy in reducing recurrence rates and enhancing long-term disease control in low-risk papillary thyroid cancer patients. While total thyroidectomy alone is effective, the addition of RAI therapy provides a marked improvement in treatment responses and reduces the risk of disease recurrence. This indicates that personalized treatment plans incorporating RAI may offer significant advantages in managing low-risk PTC., (© 2024. The Author(s).)

Telomerase reverse transcriptase promoter (TERTp) mutations are associated with non-radioiodine avidity. However, the role of these mutations in the clinical outcomes of patients with radioiodine-refractory differentiated thyroid cancer (RAIR-DTC) remains unknown. Herein, we aim to analyze gene mutations and clinical manifestations to verify TERTp's role in driving disease progression to RAIR-DTC and clinical outcomes. Next-generation sequencing data and clinical data were obtained from 243 patients with DTC. Of the 25 patients with TERTp mutations, 80% (20/25) had RAIR-DTC. RAIR-DTC was significantly less prevalent in patients with BRAF V600E (9/143, 6.3%) than those with both BRAF V600E and TERTp mutations (14/17, 82.4%). Patients with RAIR-DTC harboring both BRAF V600E and TERTp mutations were more likely to have > 3 distant metastatic sites (85.7%, 12/14) than those with BRAF V600E alone (33.3%, 3/9). Only one patient with both BRAF V600E and TERTp mutations had non-RAIR-DTC. The time from initial radioactive iodine therapy to RAIR-DTC diagnosis was significantly shorter in patients with TERTp mutations than in those without. Patients with BRAF V600E and TERTp mutations progressed faster to RAIR-DTC than those with BRAF V600E alone (p < 0.01). Our findings suggest that molecular testing for TERTp and other mutations like BRAF V600E may inform early diagnosis, prognosis, and treatment strategies before progression to RAIR-DTC., (© 2024. The Author(s).)

This study explored the role of radioiodine therapy (RAI) in low-risk thyroid cancer patients and examined the disease-specific survival (DSS) rates in a large cohort of differentiated thyroid cancer patients (DTC). We obtained patient data from SEER database. Patients who underwent total thyroidectomy were included and categorized into three groups based on histology: classical papillary thyroid carcinoma (C-PTC), follicular type variant carcinoma (FV-PTC), and follicular thyroid cancer (FTC). Patients with distant metastasis, tumor size ≥ 200 mm, chemotherapy, or any type of radiation other than RAI were also excluded. A nomogram was developed and tested for discrimination and calibration. In total, 96,532 thyroid cancer cases were examined, including 59,460 C-PTC, 31,583 FV-PTC, and 5,489 FTC cases. Age > 65 years and male sex were correlated with lower survival rates across the subtypes. In addition, extrathyroidal extension had a worse survival effect in patients with FTC. DSS rates were compared between patients who received RAI and those who did not, with a 3% difference in C-PTC (94% vs. 91%, p < 0.001), 2% in FV-PTC (92% vs. 90%, p < 0.001), and 1% in FTC (89% vs. 88%, p = 0.084) at 15 years. The nomograms for long-term DSS showed high discriminatory abilities with C-indices of 0.815, 0.805, and 0.781 for C-PTC, FV-PTC, and FTC, respectively. The developed nomogram can be used in the treatment plan for patients with DTC. Our study emphasizes the prognostic factors for DTC and highlights the need for personalized treatment plans based on individual risk profiles., (© 2024. The Author(s).)

Objective: Patients with pediatric differentiated thyroid carcinoma (DTC) treated with radioiodine (RAI) therapy may experience long-term side effects, such as gonadal dysfunction. Therefore, it is crucial to understand the impact of this therapy on ovarian reserve and future pregnancy rates., Subjects and Methods: Retrospective analysis of 64 female DTC survivors of childbearing age to assess the risk of infertility due to RAI performed before the age of 19 years., Results: Thirty-two out of the 64 DTC survivors had a history of at least one pregnancy during follow-up. No significant differences were observed between the cumulative RAI activity, treatment regimens (multiple versus single RAI treatment), age at first treatment, or presence of lymph node or distant metastases. Notably, the group without a history of pregnancy had a younger age at the time of diagnosis and larger tumors. Age at first pregnancy was slightly higher than that in the general population, but no increase in negative maternal or fetal outcomes was observed., Conclusions: The results of this study show little observational evidence suggesting important adverse effects of RAI on fertility or pregnancy outcomes among female survivors of childhood DTC. Still, studies including larger populations are warranted., Competing Interests: Disclosure: no potential conflict of interest relevant to this article was reported.

Purpose: The aim of this study was evaluate biochemical incomplete response (BIR) in Middle Eastern differentiated thyroid cancer (DTC), identify factors that could predict BIR before radioactive iodine (RAI) ablation and to investigate the long-term clinical outcome of DTC patient exhibiting BIR to initial therapy., Methods: We retrospectively evaluated 1286 DTCs from Middle Eastern ethnicity who underwent total thyroidectomy and RAI therapy. Demograpic and clinico-pathological factors predicting BIR were evaluated. The outcome of these patients was analyzed using primary outcome of structural disease and disease-free survival (DFS)., Results: With a median follow-up of 10 years, 266 (20.7%) patients had BIR. High pre-ablation stimulated thyroglobulin (presTg), presence of lymph node metastasis, male gender and delayed initial RAI therapy (≥3 months) after thyroidectomy were significant independent predictors of BIR. Upon evaluating long-term clinical outcomes in 266 patients with BIR, we found 36.8% of patients developed structural disease. Male sex (OR = 1.56; 95% CI = 1.05-2.30; p = 0.0272) and increasing Tg after initial therapy (OR = 4.25; 95% CI = 1.93-10.82; p = 0.0001) were independent risk factors for structural disease in patients with BIR. DFS was significantly worse if both these risk factors existed concomitantly (p < 0.0001)., Conclusion: To achieve the fair efficacy of RAI therapy, early prediction of BIR before RAI ablation is desirable. Our finding of the clinico-pathological factors (high presTg level, LNM, delayed RAI therapy and male gender) could serve as easy and robust early predictors of BIR. In addition, DTC patients exhibiting BIR had a high risk of structural disease and hence personalized management approach would be preferable for BIR patients to ensure best clinical outcome., (© 2024. The Author(s).)

Purpose: Evaluating the impact of radioiodine therapy (RIT) on olfactory function in thyroid cancer patients through quantitative and qualitative olfactory tests., Method: In this cohort study, patients with thyroid cancer were included. Demographic, clinical, and laboratory data were collected. To subjectively evaluate the olfactory changes aftter RIT, the Visual Analog Scale (VAS), Self-Reported Mini-Olfactory Questionnaire (self-MOQ), and the University of Washington Quality of Life Questionnaire (UW-QOL) were assessed. Out of UW-QOL questions those related to saliva, taste, and overall health condition were analysed. For objective assessment, patients underwent both the Butanol Threshold Test (BTT) and the a version of Smell Identification Test (SIT). Patients were assessed before, one month, and six months after RIT., Results: Ninety eight patients were included (Male = 17). A statistically significant decrement was observed in olfaction based on the VAS, between the baseline and one (pvalue = 0.015) and six months (pvalue = 0.031) of follow-up. Additionally, saliva (pvalue = 0.001), taste (pvalue = 0.000), and overall health condition (pvalue = 0.010) significantly decreased one-month after RIT. The measures were not different between the baseline and 6-month follow up and the improvement of index of taste was significant from 1-month to 6-months follow ups (pvalue = 0.000). However, none of the objective tests (the BTT and the SIT) indicated a significant decline in olfaction during the follow up., Conclusion: A subjective RIT related decrease in smell function, taste, and saliva production was documented without any objective olfactory dysfunction., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Oncocytic carcinoma of the thyroid (OCA) is an independent type of thyroid cancer. Radioactive iodine (RAI) therapy was frequently administered to OCA patients, but its contribution to improving survival is indefinite., Methods: 4641 OCA patients from 2000 to 2018 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Cox proportional hazard regression and competing risk analysis were applied., Results: Tumor size, SEER stage, primary surgery, and neck dissection were prognostic factors for cancer-specific survival. The results of competing risk analysis demonstrated that age over 55 years dramatically increased non-OCA death risks. Treatments that improve non-OCA survival (including total thyroidectomy, RAI therapy, and systemic therapy) should be recommended in OCA patients older than 55 years of age. Neck lymphadenectomy should not be recommended for OCA, since the metastatic lymph node ratio was low (about 3%)., Conclusions: RAI therapy can improve survival in OCA by reducing noncancer death risks., (© 2024 The Authors. Head & Neck published by Wiley Periodicals LLC.)

Background: While radioactive iodine (RAI) therapy in older adults with differentiated thyroid carcinoma (DTC) reduces recurrence, data in pediatrics remain limited. We conducted a meta-analysis to quantify outcomes and recurrence risk with RAI versus thyroidectomy alone in the pediatric population., Methods: Systematic literature review identified 34 retrospective studies including 2913 DTC patients under age 22 years (published 2005-2023). Meta-analysis calculated pooled rates of disease persistence and recurrence. Relative risk ratios compared odds of recurrence with RAI versus no RAI., Results: Patients had mean age 14.7 years (95 % CI, 14.2-15.2) and were 75.9 % female (95 % CI, 73.8-78.1 %). Majority (90.2 %) received RAI. Pooled persistence rate was 30.3 % (95 % CI, 21.7-39.5 %); higher with RAI (31.5 %; 95 % CI, 22.4-41.3 %) than no RAI (4.5 %; 95 % CI, 0.0-18.7 %) (OR 3.28; 95 % CI,1.82-5.91; p < 0.001). Recurrence rate was 8.97 % (95 % CI, 4.78-14.3 %). Those with RAI had 53.1 % lower recurrence risk versus no RAI (RR 0.47; 95 % CI, 0.27-0.82; p = 0.007). Median follow-up was 7.2 years (95 % CI, 5.8-8.5 years), with no association between follow-up duration and recurrence (r = -0.053; p = 0.80)., Conclusions: RAI therapy as an adjunct to thyroidectomy is associated with a significantly lower risk of long-term recurrence in pediatric DTC. These findings advocate for the use of RAI in preventing recurrence among high-risk pediatric patients with DTC., (Published by Elsevier Ltd.)

Objective: Thyroid cancers are on the rise, but the associated vital prognosis and long-term survival rates are very good. Therefore, treated patients' quality of life and psychological well-being are important considerations. The treatment usually involves surgery and radioactive iodine (radioiodine) ablation. This study aims to investigate potential effects of radioiodine ablation therapy on health-related quality of life, anxiety and depression symptoms, and nutritional status at 6 months post-therapy., Methods: This study included 136 patients diagnosed with thyroid cancer. Absorbed doses to the salivary glands were estimated from dosimeters worn by patients. Patient health-related quality of life, psychological status and nutritional status were assessed before and 6 months after therapy using standardized questionnaires (including SF-36, Hospital Anxiety and Depression (HAD) scale). Statistical analyses included random-effects logistic and linear regressions adjusted for potential confounders., Results: While no significant association was found between radioiodine exposure and anxiety or depression symptoms, or nutritional status, a significant increase in the SF-36 role physical sub- score was observed in relation with the salivary gland dose (β= 6.54, 95%CI 2.71;10.36 for a 1-Gy increase)., Conclusions: The findings suggest an improved physical health-related quality of life, namely reduced pain and functional impairment, 6 months after radioiodine therapy in thyroid cancer patients. No significant association was found between radioiodine exposure and mental health-related quality of life, anxiety or depression scores nor nutritional status. This study does not provide any evidence that radioiodine therapy has a potentially adverse effect on patient health-related quality of life., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The role of external beam radiotherapy (EBRT) in thyroid cancer (TC) remains contentious due to limited data. Retrospective studies suggest adjuvant EBRT benefits high-risk differentiated thyroid cancer (DTC) and limited-stage anaplastic thyroid carcinoma (ATC), enhancing locoregional control and progression-free survival when combined with surgery and chemotherapy. Intensity-modulated radiotherapy (IMRT) and particle therapy (PT), including protons, carbon ions, and Boron Neutron Capture Therapy (BNCT), represent advances in TC treatment. Following PRISMA guidelines, we reviewed 471 studies from January 2002 to January 2024, selecting 14 articles (10 preclinical, 4 clinical). Preclinical research focused on BNCT in ATC mouse models, showing promising local control rates. Clinical studies explored proton, neutron, or photon radiotherapy, reporting favorable outcomes and manageable toxicity. While PT shows promise supported by biological rationale, further research is necessary to clarify its role and potential combination with systemic treatments in TC management., Competing Interests: Declaration of Competing Interest None declared, (Copyright © 2024 Elsevier B.V. All rights reserved.)

Introduction: Radioactive iodine (RAI) has been utilized for nearly 80 years in treating both hyperthyroidism and thyroid cancer, and it continues to play a central role in the management of differentiated thyroid cancer (DTC) today. Recently, the use of RAI therapy for indolent, low-risk DTC has generated considerable debate. This case-control study evaluated the therapeutic response in DTC patients, comparing outcomes between those who received RAI therapy and those who did not., Methods: The study included individuals diagnosed with either indolent or aggressive histological types of DTC who either underwent RAI therapy or did not. For each patient, information regarding demographics (age, sex, background), clinical data, laboratory parameters, pathological exam, history of RAI therapy, thyroid ultrasound findings, and loco-regional or distant metastasis was extracted. All group comparisons were made using a two-sided test at an α level of 5%., Results: Out of 104 patients diagnosed with DTC, 76 met the inclusion criteria and were subsequently divided into two primary groups based on their history of RAI ablation. The majority of patients underwent RAI therapy (76.3%). Most patients had a good biochemical (68.4%, p = 0.246) and structural control (72.4%, p = 0.366), without a significant difference between the two groups. RAI therapy significantly protected against incomplete biochemical control in the overall population (p = 0.019) and in patients with histological indolent DTC (p = 0.030). Predictive factors for incomplete biochemical control included male sex (p = 0.008) and incomplete structural control (p = 0.002) across all patients, regardless of the histological type., Discussions: While RAI therapy has traditionally been used to manage DTC, our study found no significant difference in biochemical and structural responses between patients who received RAI therapy and those who did not. However, RAI therapy emerged as a protective factor against incomplete biochemical control, even in histological indolent DTC cases. These findings suggest that while RAI therapy may not be universally necessary, it could be beneficial in reducing the risk of biochemical recurrence in select patient subgroups, such as those with incomplete structural control or male patients. Thus, a personalized approach to RAI therapy, tailored to individual risk factors, may improve patient outcomes without overtreatment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Tiucă, Tiucă, Pop and Paşcanu.)

Context: Lenvatinib is approved for the treatment of radioiodine-refractory differentiated thyroid cancer (RR-DTC). The definition of predictive factors of survival is incomplete., Objective: To identify pre- and posttreatment survival predictors in a real-life cohort of RR-DTC treated with lenvatinib., Design: Multicenter, retrospective, cohort study., Setting: 3 Italian thyroid cancer referral centers., Participants: 55 RR-DTC treated with lenvatinib., Main Outcome Measures: Progression-free survival (PFS) and overall survival (OS)., Results: Lenvatinib was the first-line kinase-inhibitor in 96.4% of subjects. Median follow-up was 48 months. Median PFS and OS were 26 [95% confidence interval (CI) 19.06-32.93] and 70 months (95% CI 36-111.99), respectively. Pretreatment setting: Eastern Cooperative Oncology Group (ECOG) performance status was independently related to PFS [P < .001; hazard ratio (HR) 18.82; 95% CI 3.65-97.08: score 0-1 as reference] and OS (P = .001; HR 6.20; 95% CI 2.11-18.20; score 0-1 as reference); radioactive iodine (RAI) avidity was independently related to PFS (P = .047; HR 3.74; 95% CI 1.01-13.76; avid disease as reference). Patients with good ECOG status (0-1) and RAI-avid disease obtained objective response in 100% of cases and achieved a median PFS of 45 months without any death upon a median follow-up of 81 months. Posttreatment setting: the best radiological response independently predicted PFS (P = .001; HR 4.6; 95% CI 1.89-11.18; partial/complete response as reference) and OS (P = .013; HR 2.94; 95% CI 1.25-6.89; partial/complete response as reference)., Conclusion: RR-DTC with good performance status and RAI-avid disease obtains the highest clinical benefit from lenvatinib. After treatment initiation, objective response was the only independent survival predictor., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Objective: Patients with radioiodine-refractory (RAIR) differentiated thyroid carcinoma (DTC; RAIR-DTC) have a poor prognosis. The aim of this study was to provide new insights and possibilities for the diagnosis and treatment of RAIR-DTC., Methods: The metabolomics of 24 RAIR-DTC and 18 non-radioiodine-refractory (NonRAIR) DTC patients samples were analyzed by liquid chromatograph-mass spectrometry. Cellular radioiodine uptake was detected with γ counter. Sodium iodide symporter (NIS) expression and thyroid stimulating hormone receptor (TSHR) were measured by Western blot analysis. CCK8 and colony formation assays were used to measure cellular proliferation. Scratch and transwell assays were performed to assess cell migration and invasion. Annexin V/PI staining was used to detect cell apoptosis. Cell growth in vivo was evaluated by a tumor xenograft model. The acetoacetate (AcAc) level was measured by ELISA. Pathological changes, Ki67, NIS, and TSHR expression were investigated by immunohistochemistry., Results: The metabolite profiles of RAIR could be distinguished from those of NonRAIR, with AcAc significantly lower in RAIR. The significantly different metabolic pathway was ketone body metabolism. AcAc increased NIS and TSHR expression and improved radioiodine uptake. AcAc inhibited cell proliferation, migration, and invasion, and as well promoted cell apoptosis. Ketogenic diet (KD) elevated AcAc levels and significantly suppressed tumor growth, as well as improved NIS and TSHR expression., Conclusion: Significant metabolic differences were observed between RAIR and NonRAIR, and ketone body metabolism might play an important role in RAIR-DTC. AcAc improved cellular iodine uptake and had antitumor effects for thyroid carcinoma. KD might be a new therapeutic strategy for RAIR-DTC., (© The Author(s) 2024. Published by Oxford University Press.)

Objectives: We introduced selpercatinib prior to radioactive iodine therapy prior to radioactive iodine therapy (RAI) for pediatric papillary thyroid cancer (PTC) to enhance the tumorical effects of RAI., Case Presentation: PTC has an excellent prognosis but is commonly associated with local and distant metastases. Successful complete response to the current standard of care, thyroidectomy with lymph node resection and RAI, is achieved in only a small minority of cases with metastases. The direct effect of tyrosine kinase inhibitors (TKIs) on tumor regression has been confirmed in several randomized controlled studies, while the increased RAI uptake has been reported in small case series, but typically TKIs are currently reserved third-line. Selpercatinib is a TKI that specifically has a durable effect in RET-fusion positive malignancies. We describe a 10-year-old Hispanic girl with metastatic PTC treated with total thyroidectomy and extensive lymph node resection. Evaluation for relevant genetic drivers of the malignancy revealed a strong overexpression of the RET tyrosine kinase domain indicative of a RET gene fusion. Selpercatinib 120 mg twice daily given orally was initiated prior to the initial dose of RAI to achieve further tumor regression by a direct cytostatic effect and then secondarily enhancement of RAI uptake. Minimal side effects occurred, specifically intermittent mild skin rashes that resolved. Resolution of distal lung metastases was noted on CT imaging. RAI was then administered 9 months afterward, with ultimately achievement of a low thyroglobulin level 1.0 ng/mL 11 months after RAI., Conclusions: In conclusion, selpercatinib given prior to the initial dose of adjunctive RAI for RET-fusion positive PTC is a well-tolerated intervention that further reduces tumor burden and potentially enhances the tumorcidal effects of RAI., (© 2024 Walter de Gruyter GmbH, Berlin/Boston.)

High-activity radioactive iodine (RAI) therapy for metastatic thyroid cancer (TC) requires isolation to minimize radiation exposure to third parties, thus posing challenges for patients needing hands-on care. There are limited data on the approach to high-activity RAI treatment in paraplegic patients. We report a state-of-the-art multidisciplinary approach to the management of bedbound patients, covering necessary radiation safety measures that lead to radiation exposure levels as low as reasonably achievable. Given the limited literature resources on standardized approaches, we provide a practical example of the safe and successful treatment of a woman with BRAFV600E -mutant tall-cell-variant papillary TC and pulmonary metastases, who underwent dabrafenib redifferentiation before RAI therapy. The patient was 69 y old and had become paraplegic because of a motor-vehicle accident. Since caring for a paraplegic patient with neurogenic bowel and bladder dysfunction poses radiation safety challenges, a multidisciplinary team comprising endocrinologists, nuclear medicine physicians, radiation safety specialists, and the nursing department developed a radiation mitigation strategy to ensure patient and staff safety during RAI therapy. The proposed standardized approach includes thorough monitoring of radiation levels in the workplace, providing additional protective equipment for workers who handle radioactive materials or are in direct patient contact, and implementing strict guidelines for safely disposing of radioactive waste such as urine collected in lead-lined containers. This approach requires enhanced training, role preparation, and practice; use of physical therapy equipment to increase the exposure distance; and estimation of the safe exposure time for caregivers based on dosimetry. The effective and safe treatment of metastatic TC in paraplegic patients can be successfully implemented with a comprehensive radiation mitigation strategy and thorough surveying of personnel for contamination., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Objective: The aim of this study is to assess the impact of extrathyroidal autoimmune diseases (ADs) on the clinical characteristics and efficacy of iodine-131 ( 131 I) therapy in patients with differentiated thyroid cancer (DTC)., Methods: Patients with DTC who were received 131 I therapy simultaneously were classified into the combination group (n = 35) and noncombination group (n = 146) depending on the presence of ADs. The clinical characteristics, such as gender, age, tumor lesions, lymph node metastasis, distant metastasis, 131 I therapy efficacy, and use of levothyroxine, were compared between the two groups. Statistical analysis was conducted using SPSS 26.0 and R 4.0.3., Results: There was a statistically significant difference in age between the combination and noncombination groups (t = -2.872, p < .01), and the optimal cutoff value was 50.5 years. Propensity score matching was completed effectively on a total of 121 patients, using age as the matching factor, comprising 32 cases in the combination group and 80 cases in the noncombination group. The baseline demographic features of the two groups were equivalent after matching (p > .05), and there was no significant difference in the therapeutic efficacy of 131 I between the two groups (p > .05). In the subgroup analysis involving patients aged great than 50.5 years, the levothyroxine/weight (µg/kg) was increased in the combination group, and the difference was statistically significant (p < .05)., Conclusion: While extrathyroidal ADs may enhance the detection of DTC among elderly women, they have no impact on the clinical characteristics of thyroid cancer or the efficacy of 131 I therapy. ADs may necessitate higher per-unit dosages of levothyroxine in patients with DTC, regardless of the clinical status. Consequently, it is not essential for nuclear medicine physicians to consider the presence of ADs when designing treatment plans for patients with DTC., (© 2024 The Author(s). Immunity, Inflammation and Disease published by John Wiley & Sons Ltd.)

Differentiated thyroid cancer (DTC) is the most common endocrine malignancy. Patients who receive systematic care typically have a better prognosis. RAI treatment plays a key role in eradicating any remaining thyroid lesions in DTC patients, hence decreasing the risk of distant metastases and cancer recurrence. As research continues to advance, RAI treatment is becoming more and more individualized. Because of the excellent prognosis for DTC patients, there is a relatively broad window for RAI treatment, making it easy to overlook when to receive RAI treatment. However, research on this issue can help patients with varying recurrence risk stratification make better decisions about when to begin RAI treatment following surgery, and physicians can schedule patients based on the severity of their disease. This will improve patient prognosis and lessen needless anxiety in addition to helping solve the problems of unjust healthcare resource distribution. In this review, we will mainly discuss the target population of RAI treatment as well as studies that examine the impact of RAI treatment timing on patient outcomes. In an effort to discourage DTC patients and physicians from selecting RAI therapy at random, we also review the possible negative effects of this treatment., (© 2024. The Author(s) under exclusive licence to The Japanese Society of Nuclear Medicine.)

Thyroglobulin (Tg) is an important tool to evaluate the persistence and recurrence risk in differentiated thyroid cancer (DTC). We aimed to evaluate the correlation between pre-radioiodine therapy stimulated Tg (pre-RAI Tg) levels and the first response to treatment evaluation, and to establish a cut-off pre-RAI Tg threshold for predicting an initial excellent response. Retrospective cohort study of DTC patients who underwent total thyroidectomy and radioiodine therapy. Response to therapy was evaluated 6 to 24 months after initial therapy, and patients were classified as: excellent response (ER); indeterminate response (IndR) and incomplete response (IncR). Total patients: 166 among which 85.5% female with mean age of 47.6 ± 13 years. The ER had a significantly lower pre-RAI Tg in comparison to IndR (p<0.001) and IncR (p<0.001), and pre-RAI Tg were different between the IndR and IncR (p=0.02). A cut-off pre-RAI Tg value at 7.55ng/ml was obtained by receiver operating characteristics curve for differentiating ER from IndR and IncR. The area under curve was 0.832 (95% CI 0.76-0.91). In multivariate analysis, ATA low-risk (RR 1.61, 95% CI 1.06-2.43, p=0.025) and Tg below 7.55ng/ml (RR 2.17, 95% CI 1.52-3.10, p<0.001) were associated with ER. After a median of 7.4-year follow-up, 124 (74.7%) patients were allocated into ER, 22 (13.2%) into IndR, and 20 (12%) into IncR. In conclusion, pre-RAI Tg predicts first evaluation of treatment response. Pre-RAI Tg cut-off was a key predictor of initial excellent response to therapy and may be an important tool in the follow-up of DTC patients., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Background: Although standard operational procedures for pre-therapeutic dosimetry already exist for the determination of the maximum safe activity to treat differentiated thyroid cancer patients, empiric activity administration of 131 I is still the most frequent way of treatment. In this way, the absorbed dose to the blood/bone marrow remains unknown., Purpose: In this work, we present a strategy to estimate radiation dose to the blood in an outpatient setting., Methods: A mobile application was developed, which together with an off-the-shelf compact semiconductor radiation detector allows the determination of whole-body time-integrated activity coefficients. The methodology was tested in a cohort of 79 differentiated cancer patients who received therapeutic 131 I activities. Post-therapeutic whole-body time-integrated activity coefficients were compared against pre-therapeutic estimates in a subset of 13 patients., Results: The 95% limits of agreement between pre whole-body and post whole-body time integrated activity coefficients were [-14.4; 6.6] h when considering outliers and [-6.2; 3.6] h without outliers. A high dispersion in blood dose coefficients was found, with a four-fold difference between the highest and lower values. Blood doses were significantly higher for patients treated with dosimetrically guided activities than for empirical activities (median dose = 118 vs. 49 cGy, respectively). Blood dose coefficients were significantly lower for patients prepared with recombinant human thyroid stimulating hormone (rhTSH) than for patients prepared with thyroid hormone withdrawal. A low correlation between blood dose and administered activity was found in empirically treated patients (R 2  = 0.26)., Conclusions: We successfully implemented a post-therapeutic internal dosimetry methodology for differentiated thyroid cancer therapy with 131 I, which allows to estimate dose to the blood from outpatient measurements with mobile devices. The proposed methodology avoids the need of daily visits to the nuclear medicine department, thus reducing the burden for the patient and for the staff., (© 2024 American Association of Physicists in Medicine.)

Background: It remains unclear whether the time interval between total thyroidectomy and radioactive iodine (RAI) therapy influences clinical outcomes in papillary thyroid carcinoma (PTC). This study aims to evaluate the impact of the timing to initiate RAI therapy on the response in PTC patients., Methods: We retrospectively included 405 patients who underwent total thyroidectomy and subsequent RAI therapy at two tertiary hospitals in southwest China. Patients were categorized into two groups based on the interval between thyroidectomy and initial RAI therapy, that is, an early group (interval ≤90 days, n  = 317) and a delayed group (interval >90 days, n  = 88). Responses to RAI therapy were classified as excellent, indeterminate, biochemical incomplete, or structural incomplete. Univariate and multivariate analyses were conducted to identify factors associated with a nonexcellent response., Results: Excellent responses were observed in 77.3% of the early group and 83.0% of the delayed group ( P  = 0.252). No significant impact of RAI therapy timing was also observed across all American Thyroid Association risk classification categories. These findings persisted when patients were analyzed separately according to RAI dose (intermediate-dose group: 3.7 GBq [ n  = 332]; high-activity group: ≥5.5 GBq [ n  = 73]), further subdivided by the timing of RAI therapy. Multivariate analysis identified lymph node dissection, RAI dose, and stimulated thyroglobulin as independent risk factors for excellent response ( P  < 0.05)., Conclusion: The timing of initial RAI therapy following surgery did not significantly affect outcomes in patients with PTC., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Background: The extent of thyroid surgery for multifocal papillary thyroid microcarcinoma (PTMC) remains controversial. Studies on the optimal surgical approach for a multifocal PTMC are scarce. This study aimed to compare the effectiveness of thyroidectomy and lobectomy for the treatment of multifocal PTMC., Methods: A population-based retrospective cohort of patients with multifocal PTMC was analyzed using the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2017, and divided into two groups (thyroidectomy, lobectomy) based on the surgical approach. The clinicopathologic features and survival outcomes were compared between the two groups. Cox proportional hazards regression analysis to explore prognostic factors of survival. Propensity score matching (PSM) was used to balance covariates., Results: Overall, a total of 9387 multifocal PTMC patients were included in the study. Among them, 8,107 (86.36%) patients received thyroidectomy, and 1280 (13.64%) patients underwent lobectomy. Compared to patients in the thyroidectomy group, patients in the lobectomy group were diagnosed with older age (50.47 years vs. 49.32 years, p = 0.003), a higher proportion of males (20.47% vs. 14.99%, p < 0.001), larger tumors (6.22 mm vs. 4.97 mm, p < 0.001), and more frequently underwent radiotherapy (35.40% vs. 10.16%, p < 0.001). Multivariate Cox regression analysis revealed that age was the only independent prognostic factor for thyroid cancer-specific survival (TCSS), and the determinants of overall survival (OS) were age and gender. Unadjusted survival analysis revealed no difference between the two treatment groups in TCSS (p = 0.598) and OS (p = 0.126). After 1:1 Propensity Score Matching (PSM), there was still no difference in TCSS (p = 0.368) or OS (p = 0.388). The stratified analysis revealed that for patients aged under or above 55, thyroidectomy was not associated with superior BCSS or OS (p > 0.05)., Conclusions: Thyroidectomy was not associated with improved survival compared to thyroid lobectomy for patients with multifocal PTMC., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: To evaluate the safety and efficacy of radiofrequency ablation (RFA) in treating locoregional recurrent thyroid cancer (LRTC) after a 2-year follow-up time., Methods: PubMed, Embase and Cochrane Library were searched from inception until 20 September 2022 to find studies reporting the safety and efficacy of RFA in LRTC patients after a 2-year follow-up. Two radiologists performed the data extraction and methodological quality assessment according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines., Results: We analyzed 6 studies, 229 LRTC patients with 319 locally recurrent tumors were treated with RFA. The mean follow-up time of each study was ≥24 months. The pooled changes in the largest diameter and volume were 7.22 mm (95% confidence interval (CI), 6.35-8.09 mm) and 164.28 mm 3 (95% CI, 87.78-240.77 mm 3 ), respectively; the pooled volume reduction rate was 95.03% (95% CI, 87.56-102.49%). The total complete disappearance rate after treatment was 92% (95% CI, 83-100%). The pooled decrease of serum thyroglobulin levels was 0.02 ng/ml (95% CI, -0.00-0.04 ng/ml). The pooled proportion of recurrence rate was 6% (95% CI, 0-13%). The pooled complication rate was 5% (95% CI, 0-10%). The major complications were voice change and hoarseness, only one patient developed permanent vocal cord paralysis; minor complications were cough and pain., Conclusions: Ultrasound-guided RFA is an effective and safe treatment for LRTC based on 2-year follow-up results., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The prevalent histological variant within differentiated thyroid carcinoma is papillary thyroid carcinoma, also known as PTC. The study investigated the clinical performance of serum hsa&#95;circ&#95;0001955 in predicting the prognosis of PTC treated with radical thyroidectomy and iodine 131 nail clearance. The relative expression of serum circ&#95;0001955 of PTC patients was detected before and after accepting radical thyroidectomy combined with 131I thyroid remnant ablation by RT-qPCR. Serum thyroglobulin (Tg) and thyroglobulin antibody (TgAb) levels were quantified by an automatic chemiluminescence immunoassay analyzer. Multivariate logistic regression analysis was employed to investigate the risk factors associated with the prognosis of PTC patients with postoperative 131I therapy. The serum circ&#95;0001955 levels in 127 PTC patients were higher than that in 96 multinodular goiter patients and 110 healthy controls before treatment and had diagnostic values for PTC patients. After 131I treatment, serum circ&#95;0001955 levels and Tg value have a correlation with potential recurrence (WBS positive). Serum circ&#95;0001955, Tg, and TgAb value, and their combination may have diagnostic value in predicting recurrence. Serum circ&#95;0001955 levels in patients with PTC after radical thyroidectomy and iodine 131 thyroidectomy may help predict recurrence.

Objective: We conducted a prospective randomized clinical trial to compare the efficacy of low- and high-dose radioiodine for remnant ablation in patients with low-risk differentiated thyroid cancer (DTC) in China. The first-stage results showed equivalence was observed between the two groups. Here, we report recurrence and survival at 3-5 and 6-10 years and biochemical parameters., Design, Patients and Methods: Between January 2013 and December 2014, adult patients with DTC were enroled. Patients had undergone total or near-total thyroidectomy, with or without cervical lymph node dissection, with tumour stages T1-T3 with or without lymph node metastasis, but without distant metastasis. Patients were randomly assigned to the low-dose (1850 MBq) or high-dose (3700 MBq) radioiodine group. They were then followed up for 3-5 and 6-10 years. Data on biochemical abnormalities, recurrence and survival were analysed using Kolmogorov-Smirnov and χ 2 tests., Results: The data of 228 patients (mean age = 42 years; 70.6% women) were analysed, with 117 patients in the low-dose group and 111 in the high-dose group. There were no significant differences in biochemical abnormalities, recurrence, or survival rates at the 6-10-year follow-up (all p > .05). Nine patients experienced recurrence in the low-dose group (8.7%), while eight patients experienced recurrence in the high-dose group (8.2%). The survival rates were 100% and 98.2% in the low- and high-dose groups, respectively., Conclusions: The long-term effectiveness and safety of low-dose (1850 MBq) radioiodine are the same as those of high-dose (3700 MBq) radioiodine for thyroid remnant ablation in Chinese patients with low-risk DTC., (© 2024 John Wiley & Sons Ltd.)

Purpose: Differentiated thyroid cancer (DTC) presents a complex clinical challenge, especially in patients with distant metastases and resistance to standard treatments. This study aimed to investigate the influence of specific genes and their germline single nucleotide polymorphisms (SNPs) linked to both inflammatory processes and other neoplasms on the clinical and pathological characteristics of DTC, particularly their potential impact on radioiodine (RAI) treatment efficacy., Methods: This retrospective analysis involved a cohort of 646 patients diagnosed with DTC after thyroidectomy. Study covering 1998-2014, updated in 2023, included 567 women and 79 men (median age: 49; range: 7-83). SNP selection targeted functional significance, while mutational status was assessed by pyrosequencing for comprehensive characterization. Patient genetic profiles were assessed for associations with disease characteristics, RAI response, and cancer pathology., Results: Significant correlations emerged between certain SNPs and DTC features. Notably, the NOD2 c.802 T > C variant (rs2066842) was identified as a marker distinguishing between papillary thyroid cancer (PTC) and follicular thyroid cancer (FTC). Moreover, the c.802 T allele was associated with an enhanced response to RAI treatment, indicating a more substantial decrease in posttreatment stimulated thyroglobulin (sTg) concentrations. The NFKB1A allele c.126A (rs696) exhibited connections with lower FTC stages and a reduced probability of multifocality., Conclusion: This study explored the molecular mechanisms of particular SNPs, highlighting the role of NOD2 in innate immunity and the stress response, and its potential impact on RAI efficacy. This research underscores the clinical promise of SNP analysis and contributes to personalized treatment strategies for DTC, emphasizing the relevance of genetic factors in cancer progression and treatment outcomes., (© 2024. The Author(s).)

Purpose: This article aims to comprehensively analyze the unique challenges in managing patients with metastatic Differentiated Thyroid Cancer (DTC) that develop radioiodine-refractory disease, especially in developing countries in Latin America. We discuss key contentious aspects of their treatment, such as the optimal timing for initiating systemic therapy, the choice of first-line medications, the appropriate timing for requesting molecular interrogation, and the challenges associated with accessing these drugs and molecular panels., Methods: To illustrate these challenges and enhance understanding, we present five real clinical cases from the authors' experiences., Results: Patients with Differentiated Thyroid Cancer (DTC) generally have an excellent prognosis, with an overall 10-year survival rate exceeding 97%. However, approximately 5% of DTC patients, especially those with distant metastases, may develop radioiodine-refractory disease, reducing survival rates. Access to medications remains difficult and time-consuming, particularly for patients within the public healthcare system. Urgent discussions on drug pricing involving all stakeholders are imperative. To break free from complacency, stakeholders must prioritize patient well-being by advocating for evidence-based drug pricing, increased participation in clinical trials, and streamlined regulatory processes., Conclusion: Beyond the recognized need for prospective randomized clinical trials to determine the optimal first-line drug and the timing of molecular testing, this type of manuscript plays a pivotal role in stimulating discussions and disseminating comprehensive knowledge about the challenges associated with treating and monitoring patients with radioiodine-refractory thyroid carcinoma, especially in developing countries., Competing Interests: Compliance with ethical standards Conflict of interest Gustavo C. Penna is a speaker and participant of the Advisory Boards for Ipsen and Knight. Fabian Pitoia is a speaker and participated in Advisory Boards for Bayer and Raffo, PI Bayer, Roche, and Novartis. Aline L. F. Chaves is a speaker and participates in Advisory Boards for Merck Serono, Merck Sharpe and Dhome, Ipsen, Knight, Bayer, Eli Lilly. Kamilla M. A. Brandão Rajão is a speaker for Knight. The other authors have no financial interests., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Objective: Ionizing radiation generates genomic instability by promoting the accumulation of chromosomal rearrangements. The oncogenic translocation RET/PTC1 is present in more than 70% of radiation-induced thyroid cancers. Both RET and CCDC6, the genes implicated in RET/PTC1, are found within common fragile sites - chromosomal regions prone to DNA breakage during slight replication stress. Given that irradiated cells become more susceptible to genomic destabilization due to the accumulation of replication-stress-related double-strand breaks (DSBs), we explored whether RET and CCDC6 exhibit DNA breakage under replicative stress several days post-irradiation of thyroid cells., Methods: We analyzed the dynamic of DNA replication in human thyroid epithelial cells (HThy-ori-3.1) 4 days post a 5-Gy exposure using molecular DNA combing. The DNA replication schedule was evaluated through replication-timing experiments. We implemented a ChIP-qPCR assay to determine whether the RET and CCDC6 genes break following irradiation., Results: Our study indicates that replicative stress, occurring several days post-irradiation in thyroid cells, primarily causes DSBs in the RET gene. We discovered that both the RET and CCDC6 genes undergo late replication in thyroid cells. However, only RET's replication rate is notably delayed after irradiation., Conclusion: The findings suggest that post-irradiation in the RET gene causes a breakage in the replication fork, which could potentially invade another genomic area, including CCDC6. As a result, this could greatly contribute to the high prevalence of chromosomal RET/PTC rearrangements seen in patients exposed to external radiation.

Purpose: To develop a predictive model using machine learning for levothyroxine (L-T4) dose selection in patients with differentiated thyroid cancer (DTC) after resection and radioactive iodine (RAI) therapy and to prospectively validate the accuracy of the model in two institutions., Methods: A total of 266 DTC patients who received RAI therapy after thyroidectomy and achieved target thyroid stimulating hormone (TSH) level were included in this retrospective study. Sixteen clinical and biochemical characteristics that could potentially influence the L-T4 dose were collected; Significant features correlated with L-T4 dose were selected using machine learning random forest method, and a total of eight regression models were established to assess their performance in prediction of L-T4 dose after RAI therapy; The optimal model was validated through a two-center prospective study (n=263)., Results: Six significant clinical and biochemical features were selected, including body surface area (BSA), weight, hemoglobin (HB), height, body mass index (BMI), and age. Cross-validation showed that the support vector regression (SVR) model was with the highest accuracy (53.4%) for prediction of L-T4 dose among the established eight models. In the two-center prospective validation study, a total of 263 patients were included. The TSH targeting rate based on constructed SVR model were dramatically higher than that based on empirical administration (Rate 1 (first rate): 52.09% (137/263) vs 10.53% (28/266); Rate 2 (cumulative rate): 85.55% (225/263) vs 53.38% (142/266)). Furthermore, the model significantly shortens the time (days) to achieve target TSH level (62.61 ± 58.78 vs 115.50 ± 71.40)., Conclusions: The constructed SVR model can effectively predict the L-T4 dose for postoperative DTC after RAI therapy, thus shortening the time to achieve TSH target level and improving the quality of life for DTC patients., Competing Interests: The authors declare that financial support was received for the research, authorship, and/or publication of this article., (Copyright © 2024 Liu, Wang, Yue, Yin, Tong, Fu, Ma, Li, Liu, Zhang, Su, Yang, Li, Xu and Dai.)

Objective: Patients with non-medullary thyroid carcinoma (NMTC) that are refractory to radioactive iodine (RAI) have a poor prognosis. Strategies for restoring the ability to take up iodine, so-called redifferentiation, are promising but not suitable for all patients. Preclinical studies, in human cell lines just as in a murine model, have shown that the cardiac glycoside digoxin restored RAI uptake. This prospective single-center open-label study aimed to investigate whether treatment with digoxin could reinduce clinically relevant RAI uptake in patients with metastasized RAI-refractory NMTC., Methods: Eight patients with metastasized RAI-refractory NMTC were included between November 2022 and June 2023. Before treatment, a baseline [123I]NaI scintigraphy was performed. Thereafter, patients were treated with digoxin for 3 weeks. Starting doses depended on age and weight. For safety reasons, the usual therapeutic range was aimed for. After 1 week, the digoxin plasma concentration was measured, and the digoxin dose was adjusted if necessary. After 3 weeks of digoxin treatment, a second [123I]NaI scintigraphy was performed. RAI uptake was compared between the two scintigraphies., Results: Seven patients completed the digoxin treatment and were evaluable. None of the seven patients showed clinically relevant RAI uptake after digoxin treatment. No digoxin-related serious adverse events occurred during this trial., Conclusion: Contrary to results from preclinical trials, in this trial, 3 weeks of digoxin treatment did not reinduce RAI uptake in patients with NMTC. This highlights essential challenges regarding the approach toward optimization of studies aimed to restore the RAI uptake and its therapeutic efficacy through drug repurposing.

Background: The clinical outcomes and implications of radioactive iodine therapy (RAIT) on cancer-specific survival (CSS) in World Health Organization classification of follicular thyroid carcinoma (FTC) are not well established., Material and Methods: The data of eligible patients with minimally invasive FTC (mi-FTC), encapsulated angioinvasive FTC (ea-FTC), or widely invasive FTC (wi-FTC) between 2000 and 2020 were extracted from the Surveillance, Epidemiology, and End Results database. CSS, the primary outcome, was compared among the 3 subtypes of patients with FTC before and after adjusting for differences using propensity score matching (PSM). The patients with FTC in different subtypes were then divided into 2 groups: the RAIT group and the no-RAIT group. Cox proportional hazards regression analyses were applied to discover the relationships of factors associated with CSS in the each PSM cohort., Results: A total of 2433 patients with mi-FTC, 216 patients with ea-FTC, and 554 patients with wi-FTC were enrolled in the original cohorts, respectively. Patients with mi-FTC or ea-FTC had similar CSS (P = .805), which was better than that of patients with wi-FTC (P < .001; P = .021). Cox proportional hazards regression analysis revealed that RAIT was not associated with improved CSS in either the mi-FTC PSM cohort (hazard ratio [HR], 1.21; 95% CI, .46-3.18; P = .705) or the wi-FTC PSM cohort (HR, 0.56; 95% CI, .35-1.08; P = .086). However, subgroup analysis demonstrated that patients with wi-FTC and N1 stage (HR, 0.44; 95% CI, .20-.99; P = .018) or M1 stage (HR, 0.25; 95% CI, .11-.53; P < .001) could gain CSS advantage from RAIT., Conclusion: The RAIT can provide a CSS advantage for patients with wi-FTC who with N1-stage or M1-stage disease., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Objective: If excellent response (ER) occurs after radioactive iodine (RAI) treatment in patients with differentiated thyroid carcinoma (DTC), the recurrence rate is low. Our study aims to predict ER at 6-24 months after RAI by using machine learning (ML) methods in which clinicopathological parameters are included in patients with DTC without distant metastasis., Methods: Treatment response of 151 patients with DTC without distant metastasis and who received RAI treatment was determined (ER/nonER). Thyroidectomy ± neck dissection pathology data, laboratory, and imaging findings before and after RAI treatment were introduced to ML models., Results: After RAI treatment, 118 patients had ER and 33 had nonER. Before RAI treatment, TgAb was positive in 29% of patients with ER and 55% of patients with nonER (p = 0.007). Eight of the ML models predicted ER with high area under the ROC curve (AUC) values (> 0.700). The model with the highest AUC value was extreme gradient boosting (AUC = 0.871), the highest accuracy shown by gradient boosting (81%)., Conclusions: ML models may be used to predict ER in patients with DTC without distant metastasis., (Copyright © 2024 Società Italiana di Otorinolaringoiatria e Chirurgia Cervico-Facciale, Rome, Italy.)

Objective: To assess the outcomes of low-risk differentiated thyroid cancer (DTC) with tumour size 1 to 4 cm post-thyroidectomy in patients who never received radioactive iodine (RAI) ablation and to compare the outcomes with those who received RAI therapy., Study Design: Observational study. Place and Duration of the Study: Department of Nuclear Medicine, Karachi Institute of Radiotherapy and Nuclear Medicine (KIRAN) Hospital, Karachi, Pakistan, from January 2016 to December 2020., Methodology: A total of 130 consecutive patients of low-risk DTC of both genders aged between 18-75 years were identified who underwent thyroidectomy. Patients were classified as either being treated or not treated with RAI, based on RAI data post-thyroidectomy. Patients were followed up for two to five years depending on their date of diagnosis from 2016 to 2020, using thyroglobulin (Tg), anti-thyroglobulin (anti-Tg), and thyrotropin (TSH) levels and ultrasound neck. Association between patients who received RAI and who did not receive RAI was determined and a p-value <0.05 was considered as statistical significance., Results: Patients had mean age of 34.5 ± 10.4 years with majority of females (75.4%). Majority of the patients (94.6%) had total thyroidectomy with no neck dissection (83.1%). RAI therapy was conducted among 70.8% participants, of which, 56.9% participants received a dose of 100 mci. Most of the patients had positive outcomes as there was no recurrence among 96.2% participants. There was a significant difference in RAI therapy with total thyroidectomy as compared to subtotal, RAI dose, tumour stage, neck dissection, and lymph node involvement (p ≤0.001)., Conclusion: After complete tumour resection, a highly selected group of patients with low-risk local disease have shown low rate of recurrence when managed without RAI. Interestingly, the disease recurrence was also only seen in patients who received RAI therapy in comparison to those who did not receive RAI therapy., Key Words: Outcomes, Differentiated thyroid cancer, Radioactive iodine, Ablation therapy, Post-surgery.

Objective: To explore the implementation of low-iodine diets by medical staff caring for patients with differentiated thyroid carcinoma prior to 131 I therapy across 58 hospitals, and offer valuable insights for the development of guidelines on low-iodine diets., Methods: Convenience sampling was utilized to conduct a survey among 163 medical staff members working in nuclear medicine departments across 58 tertiary hospitals using a self-designed questionnaire., Results: Concerning the duration of the low-iodine diet prior to treatment, the medical staff's recommendations were as follows: 58.28% suggested 2-4 weeks, 31.29% recommended more than 4 weeks, 9.2% opted for 7-13 days, and 1.23% favored less than 1 week. Regarding the timing of resuming a normal diet, the respondents' recommendations ranged from immediately after treatment (1.84%) to 3 months post-treatment (8.58%), with intermediate recommendations of 2 h (8.58%), 24-48 h (14.11%), post-discharge (12.26%), and 1 month (42.94%). Furthermore, the surveyed medical staff unanimously recommended abstaining from seafood, with 90.8% also advising against the consumption of iodized salt, 91.41% recommending avoidance of iodine-containing medications, and 71.17% advising caution with moderately high-iodine foods. Notably, 75.46% of the medical staff evaluated patient compliance with the low-iodine diet. When patients failed to adhere to the diet preparation, 33.74% of healthcare workers chose to proceed with treatment. In terms of guidance sources, 96.93% of respondents relied on relevant guidelines, 66.26% referred to the literature, and 49.69% drew upon their clinical experience. During hospitalization, 58.28% of the medical staff continued to guide patients on the low-iodine diet, while only 8.59% provided such guidance after discharge. Notably, only 20.25% of the staff considered consulting the nutrition department., Conclusion: This study underscored substantial variations in the duration and selection criteria for low-iodine diets, which were linked to a scarcity of standardized evaluations. Consequently, there is an urgent need for further research to establish detailed, practical, accessible, comprehensive, and dependable implementation programs for low-iodine diets., (© 2024. The Author(s), under exclusive licence to The Author(s) under exclusive licence to The Japanese Society of Nuclear Medicine.)

Abstract: A 75-year-old woman with papillary thyroid carcinoma who underwent 131 I radioiodine treatment was incidentally found to have an established left cerebral infarct demonstrating 131 I uptake on posttherapy whole-body scan. False-positive iodine accumulation can occur in benign processes and other malignancies, necessitating awareness among nuclear medicine physicians to avoid misdiagnosing metastatic disease. SPECT/CT can be utilized to enhance diagnostic accuracy when needed., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Objectives: To investigate the clinical character of differentiated thyroid cancer (DTC) coexisting with Hashimoto's thyroiditis (HT) and provide state-of-art evidence for personalized radioactive iodine-131 therapy (RAIT) for patients coexisting with HT., Methods: From January 2000 to January 2023, PubMed, Embase, and Web of Science databases were searched for relevant original articles that published in English on the RAIT efficacy for DTC with HT. RevMan 5.4 and Stata 17.0 were used for data analysis., Results: Eleven studies involving 16 605 DTC patients (3321 with HT) were included. HT was more frequent in female (OR: 2.90, 95% confidence interval [CI]: 1.77-4.76, P < .00001). The size of tumour (MD: -0.20, 95% CI: -0.30 to -0.11), extrathyroidal extension rate (OR: 0.77, 95% CI: 0.67-0.90), and metastasis rate (OR: 0.18, 95% CI: 0.08-0.41) were less in HT, but tumour, node, metastasis (TNM) stage had no significant difference among HT and non-HT group. Disease-free survival (DFS) rate (OR: 1.96, 95% CI: 1.57-2.44, P < .00001), 5-year DFS (OR: 1.73, 95% CI: 1.04-2.89, P = .04), and 10-year DFS (OR: 1.56, 95% CI: 1.17-2.09, P = .003) were higher in HT group. The recurrent (OR: 0.62, 95% CI: 0.45-0.83, P = .002), RAIT dosage (MD = -38.71, 95% CI: -60.86 to -16.56, P = .0006), and treatment (MD: -0.13, 95% CI: -0.22 to -0.03, P = .008) were less in HT group., Conclusions: DTC coexisting with HT was associated with less invasion. DFS of HT group was higher than non-HT group after RAIT. Low-dose treatment did not impair the efficacy of RAIT in DTC with HT., Advances in Knowledge: Hashimoto's thyroiditis is a risk for DTC, but it minimalizes the progression of cancer and enhance the efficacy of RAIT, which should be considered in personalizing RAIT., (© The Author(s) 2024. Published by Oxford University Press on behalf of the British Institute of Radiology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Purpose: whole body scan (WBS) performed following diagnostic or therapeutic administration of I-131 is useful in patients with differentiated thyroid carcinoma. However, it can be falsely positive in various circumstances. We aimed to report a series of pitfalls in a clinical perspective., Methods: A search in the database PubMed utilizing the following terms: "false radioiodine uptake" and "false positive iodine 131 scan" has been made in January 2023. Among the 346 studies screened, 230 were included in this review, with a total of 370 cases collected. Physiological uptakes were excluded. For each patient, sex, age, dose of I-131 administered, region and specific organ of uptake and cause of false uptake were evaluated., Results: 370 cases of false radioiodine uptake were reported, 19.1% in the head-neck region, 34.2% in the chest, 14.8% in the abdomen, 20.8% in the pelvis, and 11.1% in the soft tissues and skeletal system. The origin of false radioiodine uptake was referred to non-tumoral diseases in 205/370 cases (55.1%), benign tumors in 108/370 cases (29.5%), malignant tumors in 25/370 cases (6.7%), and other causes in 32/370 cases (8.7%)., Conclusions: WBS is useful in the follow-up of patients with differentiated thyroid carcinoma, however it can be falsely positive in various circumstances. For this reason, it is critically important to correlate the scintigraphic result with patient's medical history, serum thyroglobulin levels, additional imaging studies and cytologic and/or histologic result., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)