Primary Mucinous Carcinoma of the Thyroid: A Case Report, Literature Review, and Immunohistochemistry Summary.

Introduction: Primary mucinous carcinoma of the thyroid is an exceedingly rare malignancy that is histologically similar to mucinous carcinoma of other sites. Accurate diagnosis is a challenging yet crucial component of clinical management for both patients and our understanding of this rare disease. Case Presentation: We report the case of a 69-year-old male patient with primary mucinous carcinoma of the thyroid. Microscopic examination of a biopsy specimen showed fibrous tissue, which was extensively and irregularly infiltrated by a cytologically malignant epithelial neoplasm showing glandular differentiation with mucin production. Immunohistochemistry demonstrated that tumor cells were positive for TTF1, thyroglobulin, CK7, and PAX8. Co-expression of TTF1 and PAX8 is most commonly seen in thyroid tumors. These findings support our diagnosis of mucinous carcinoma of thyroid origin, which is rare and highly aggressive. Conclusion: In this report, we present the only documented case of primary mucinous carcinoma of the thyroid reported in the United States in the last decade. The diagnosis of primary mucinous carcinoma of the thyroid can be challenging. Therefore, we discuss and detail the clinicopathologic tumor profile and provide more current, detailed histological criteria to assist in the diagnosis of this rare disease.

Multi-UniFocality (MUF), in contrast to multifocality, in thyroid lesions: Relation to lymphocytic thyroiditis.

Whereas multifocality typically concerns papillary thyroid carcinoma (PTC) without specification of intrathyroidal metastatic or independent nature of tumor foci, the designation of the latter as Multi-UniFocal (MUF) may be relevant for select cases. A case series involving multifocal thyroid lesions with divergent histopathological morphology and/or molecular profile, with molecular evaluation of multiple individual tumor foci per patient based on a next-generation sequencing approach, was retrospectively reviewed. Twenty-five patient cases with multifocal thyroid lesions suggestive of MUF, with 2-6 (median 3) tumor foci per patient, were described. Tumor lesions comprised diverse histopathology, including PTC, (E)FVPTC, NIFTP, FA, FTC, and oncocytic. Morphologically similar and/or diverse tumor foci harbored different molecular alterations (suggestive of non-shared clonality); with(out) coexistent similar foci harboring identical molecular alterations; or (partly) shared molecular alterations. MUF was associated with chronic lymphocytic thyroiditis in almost half of the cases. The recognition of MUF may justify the independent clinical consideration per individual tumor focus; as separate lesions albeit within a multifocal context. The potential clinical relevance and prognostic value of MUF remain to be further established.

Thyroid Incidentalomas: Scrutinizing the Mode of Detection and Evaluating its Contribution to Thyroid Cancer Diagnosis.

There is an ongoing debate about the reasons behind the increasing incidence of thyroid cancer in the last two to three decades. Here, we investigate how thyroid nodules were detected in a large series of consultations for thyroid nodular pathology. METHODS: In total, 576 patients were analyzed, with a total of 1014 nodules described. RESULTS: In 347 (60.2%) cases, the diagnosis of a thyroid nodule was incidental, mostly during imaging tests for other reasons. Incidental diagnosis occurred among all ranges of nodule diameter and between palpable and non-palpable cases, even within a small proportion of symptomatic cases. In univariate analysis, incidental diagnosis was associated with smaller nodule diameter, non-palpable nodules, asymptomatic cases, older patient age, less advanced stages (T1-2), and conservative management. After multivariate analysis, older age, euthyroidism, and smaller diameter were statistically significant. Incidental diagnosis contributed to the diagnosis of 53.8% of the cases of cancer. Advanced T stages (T3-4) were more common in non-incidental diagnoses. CONCLUSION: Our results indicate that incidental diagnosis of thyroid nodules is a significant contributor to thyroid cancer diagnosis in all ranges of nodule diameter, especially at earlier stages.

Prognostic Roles of Inflammatory Biomarkers in Radioiodine-Refractory Thyroid Cancer Treated with Lenvatinib.

Background: Inflammatory biomarkers, such as the neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR), serve as valuable prognostic indicators in various cancers. This multicenter, retrospective cohort study assessed the treatment outcomes of lenvatinib in 71 patients with radioactive iodine (RAI)-refractory thyroid cancer, considering the baseline inflammatory biomarkers. Methods: This study retrospectively included patients from five tertiary hospitals in Korea whose complete blood counts were available before lenvatinib treatment. Progression-free survival (PFS) and overall survival (OS) were evaluated based on the median value of inflammatory biomarkers. Results: No significant differences in baseline characteristics were observed among patients grouped according to the inflammatory biomarkers, except for older patients with a higher-than-median NLR (≥2) compared to their counterparts with a lower NLR (P= 0.01). Patients with a higher-than-median NLR had significantly shorter PFS (P=0.02) and OS (P=0.017) than those with a lower NLR. In multivariate analysis, a higher-than-median NLR was significantly associated with poor OS (hazard ratio, 3.0; 95% confidence interval, 1.24 to 7.29; P=0.015). However, neither the LMR nor the PLR was associated with PFS. A higher-than-median LMR (≥3.9) was significantly associated with prolonged OS compared to a lower LMR (P=0.036). In contrast, a higher-than-median PLR (≥142.1) was associated with shorter OS compared to a lower PLR (P=0.039). Conclusion: Baseline inflammatory biomarkers can serve as predictive indicators of PFS and OS in patients with RAI-refractory thyroid cancer treated with lenvatinib.

Correlation between socioeconomic indices and epidemiological indices of thyroid cancer from 1990 to 2019 year: a global ecologic study.

BACKGROUND: The incidence of thyroid cancer as the most common type of endocrine gland malignancy has risen more significantly than any malignancies in recent years. Estimated new cases of thyroid cancer in the United States in 2024 were 12,500 and 31,520 for men and women, respectively, and estimated deaths were 1,180 for women and 990 for men. Indices of socio-economic have been commonly used to measure the development of countries. Therefore, this study aimed to examine the correlation between indices of socioeconomic status and epidemiological indices of thyroid cancer throughout the world. In addition, this study has compared two indices of human development and a socio-demographic index. METHOD: This worldwide ecological study used data on thyroid cancer incidence, mortality, human development index (HDI), and sociodemographic index (SDI) between 1990 and 2019 from the Global Burden of Disease (GBD). We evaluated the correlation between incidence and mortality rates with socioeconomic indices by using Pearson's correlation coefficient. Furthermore, for the first time, the generalized additive model (GAM) was employed for modeling. The statistical software R, version 4.2.2, was used to conduct all statistical analyses. RESULTS: The correlation between the incidence of thyroid cancer and the HDI was significant and positive (r = 0.47, p-value < 0.001). While the correlation between thyroid cancer mortality and HDI was not statistically significant (r = 0.01, p-value = 0.076). Besides, the incidence of thyroid cancer was significantly positively correlated with SDI (r = 0.48, p-value < 0.001). The multiple GAM showed that for one unit increase in HDI, the risk of thyroid cancer was increased by 2.1 times (RR = 2.1, 95%CI = 2.04 to 2.19), and for one unit increase in SDI, the risk of thyroid cancer was shown to increase by 2.2 times. (RR = 2.2, 95%CI = 2.19 to 2.35). CONCLUSION: It has been evident that countries with higher incidence of thyroid cancer display higher socioeconomic indices. While, countries with higher socioeconomic indices, report lower mortality rates. However, based on the modeling results, it can be concluded that the SDI is slightly more useful in this regard. Therefore, examining the epidemiological indices of thyroid cancer by socio-economic indices can be useful to reflect a clear image of the distribution of this cancer in each country, and can be used for planning cancer prevention strategies.

Rare Thyroid Diseases Mimicking or Concealing Primitive Thyroid Neoplasms: A Call for a "Check and Double-Check" Clinical Mindset.

Clinical endocrinologists encounter in their practice patients with thyroid diseases on a daily basis. Still, diagnosis of rare structural thyroid disorders can be quite challenging. In some instances, they do not only impersonate but can also conceal, other conditions such as thyroid carcinomas. We describe a series of patients with structural thyroid disorders including 1) anaplastic thyroid carcinoma initially presenting with features of thyroid abscess; 2) unicentric hyaline vascular Castleman's disease of the thyroid embedded in a stroma of papillary thyroid carcinoma; and 3) primary thyroid lymphoma with a rapid and fulminant evolution. The common challenge in the diagnosis of these cases lies in both their low incidence and their complex presentation. We use the presentation of these cases to raise the attention related to their identification. We highlight the need for precision diagnosis to enable a patient-tailored management approach and improve patient outcomes.

Survival predictors of radioiodine-refractory differentiated thyroid cancer treated with lenvatinib in the real-life.

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 post- treatment survival predictors in a real-life cohort of RR-DTC treated with lenvatinib. DESIGN: Multicenter, retrospective, cohort study. SETTING: Three Italian thyroid cancer referral centers. PARTECIPANTS: 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% CI 19.06-32.93) and 70 months (95% CI 36-111.99), respectively. Pre-treatment setting: Eastern Cooperative Oncology Group (ECOG) performance status was independently related to PFS (p < 0.001; HR 18.82; 95% CI 3.65-97.08: score 0-1 as reference) and OS (p = 0.001; HR 6.20; 95% CI 2.11-18.20; score 0-1 as reference); radioactive iodine (RAI)-avidity was independently related to PFS (p = 0.047; 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. Post-treatment setting: best radiological response independently predicted PFS (p = 0.001; HR 4.6; 95% CI 1.89-11.18; partial/complete response as reference) and OS (p = 0.013; HR 2.94; 95% CI 1.25-6.89; partial/complete response as reference). CONCLUSIONS: RR-DTC with good performance status and RAI-avid disease obtain the highest clinical benefit from lenvatinib. After treatment initiation, objective response was the only independent survival predictor.

Risk of Subsequent Primary Cancers in Thyroid Cancer Survivors according to the Dose of Levothyroxine: A Nationwide Cohort Study.

Background: Current research has not investigated the effect of thyroid-stimulating hormone suppression therapy with levothyroxine on the risk for developing subsequent primary cancers (SPCs). This study aimed to investigate the association between levothyroxine dosage and the risk for SPCs in thyroid cancer patients. Methods: We conducted a nationwide population-based retrospective cohort study form Korean National Health Insurance database. This cohort included 342,920 thyroid cancer patients between 2004 and 2018. Patients were divided into the non-levothyroxine and the levothyroxine groups, the latter consisting of four dosage subgroups according to quartiles. Cox proportional hazard models were performed to evaluate the risk for SPCs by adjusting for variables including cumulative doses of radioactive iodine (RAI) therapy. Results: A total of 17,410 SPC cases were observed over a median 7.3 years of follow-up. The high-dose levothyroxine subgroups (Q3 and Q4) had a higher risk for SPC (adjusted hazard ratio [HR], 1.14 and 1.27; 95% confidence interval [CI], 1.05-1.24 and 1.17- 1.37; respectively) compared to the non-levothyroxine group. In particular, the adjusted HR of stomach (1.31), colorectal (1.60), liver and biliary tract (1.95), and pancreatic (2.48) cancers were increased in the Q4 subgroup. We consistently observed a positive association between high levothyroxine dosage per body weight and risk of SPCs, even after adjusting for various confounding variables. Moreover, similar results were identified in the stratified analyses according to thyroidectomy type and RAI therapy, as well as in a subgroup analysis of patients with good adherence. Conclusion: High-dose levothyroxine use was associated with increased risk of SPCs among thyroid cancer patients regardless of RAI therapy.

Combination of Dabrafenib and Trametinib in Patients with Metastatic BRAFV600E-Mutated Thyroid Cancer.

Purpose: BRAF mutations are detected in 30-80% of papillary thyroid cancer (PTC) cases. Dabrafenib and trametinib showed promising antitumor activity in patients with BRAFV600E-mutated metastatic melanoma and non-small cell lung cancer. This study aimed to evaluate the efficacy and safety of dabrafenib and trametinib in patients with metastatic BRAFV600E-mutated thyroid cancer. Materials and Methods: This was a retrospective study to evaluate the efficacy of dabrafenib and trametinib in patients with metastatic BRAFV600E-mutated PTC. The patients received dabrafenib 150 mg twice daily and trametinib 2 mg once daily at the Samsung Medical Center. This study evaluated the progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR) overall survival (OS), and safety of dabrafenib and trametinib. Results: Between December 2019 and January 2022, 27 PTC patients including 8 patients with poorly differentiated or anaplastic transformation, received dabrafenib and trametinib. The median age was 73.0 years, and the median follow-up period was 19.8 months. The majority (81.5%) had undergone thyroidectomy, while 8 patients had received prior systemic treatments. ORR was 73.1%, with 19 partial responses, and DCR was 92.3%. Median PFS was 21.7 months, and median OS was 21.7 months. Treatment-related adverse events included generalized weakness (29.6%), fever (25.9%), and gastrointestinal problems (22.2%). Dose reduction due to adverse events was required in 81.5% of the patients. Conclusion: Dabrafenib and trametinib demonstrated a high ORR with promising PFS; however, most patients with BRAFV600E-mutated metastatic PTC required a dose reduction.

Active Surveillance for Low-Risk Thyroid Cancers: A Review of Current Practice Guidelines.

The indolent nature and favorable outcomes associated with papillary thyroid microcarcinoma have prompted numerous prospective studies on active surveillance (AS) and its adoption as an alternative to immediate surgery in managing low-risk thyroid cancer. This article reviews the current status of AS, as outlined in various international practice guidelines. AS is typically recommended for tumors that measure 1 cm or less in diameter and do not exhibit aggressive subtypes on cytology, extrathyroidal extension, lymph node metastasis, or distant metastasis. To determine the most appropriate candidates for AS, factors such as tumor size, location, multiplicity, and ultrasound findings are considered, along with patient characteristics like medical condition, age, and family history. Moreover, shared decision-making, which includes patient-reported outcomes such as quality of life and cost-effectiveness, is essential. During AS, patients undergo regular ultrasound examinations to monitor for signs of disease progression, including tumor growth, extrathyroidal extension, or lymph node metastasis. In conclusion, while AS is a feasible and reliable approach for managing lowrisk thyroid cancer, it requires careful patient selection, effective communication for shared decision-making, standardized follow-up protocols, and a clear definition of disease progression.

Thyroid Metastases from Breast Cancer Case Report and Literature Review.

BACKGROUND: Thyroid metastasis arising from primary breast cancer is a rare phenomenon, with only a handful of cases documented in both national and international literature. The management approach and prognosis of this occurrence have sparked debates and uncertainties. CASE PRESENTATION: Herein, we report the case of a 55-year-old woman with breast cancer. She previously underwent extensive excision of the breast lesion with adjuvant chemotherapy and endocrine therapy. After 9 years, she presented with neck discomfort and examination suggested right thyroid metastasis and lymph node metastasis in the neck. Imaging showed pulmonary and bone metastases. Furthermore, the patient received endocrine therapy. After 7 months of follow- up, the patient survived without any new distant metastases. Thyroid metastases originating from breast cancer often unfold with a subtle, intricate nature, making early detection challenging. They tend to emerge inconspicuously, intertwining with widespread systemic metastases, hinting at a less favorable prognosis. CONCLUSION: Given the unusual clinical indicators, identifying heterochronic thyroid metastases in patients with tumors poses a distinct challenge, requiring clinicians to navigate the follow-up process with heightened sensitivity. The key lies in timely detection and early intervention, factors that can significantly enhance the overall quality of life for patients.

Assessment of the risk of malignancy in Bethesda III thyroid nodules: a comprehensive review.

The increasing prevalence of thyroid cancer emphasizes the need for a thorough assessment of risk of malignancy in Bethesda III nodules. Various methods ranging commercial platforms of molecular genetic testing (including Afirma® GEC, Afirma® GSC, ThyroSeq® V3, RosettaGX®, ThyGeNEXT®/ThyraMIR®, ThyroidPRINT®) to radionuclide scans and ultrasonography have been investigated to provide a more nuanced comprehension of risk estimation. The integration of molecular studies and imaging techniques into clinical practice may provide clinicians with improved and personalized risk assessment. This integrated approach we feel may enable clinicians to carefully tailor interventions, thereby minimizing the likelihood of unnecessary thyroid surgeries and overall crafting the optimal treatment. By aligning with the evolving landscape of personalized healthcare, this comprehensive strategy ensures a patient-centric approach to thyroid nodule and thyroid cancer management.

Sex differences and racial/ethnic disparities in the presentation and treatment of medullary thyroid cancer.

BACKGROUND: This study assessed for disparities in the presentation and management of medullary thyroid cancer (MTC). METHODS: Patients with MTC (2010-2020) were identified from the National Cancer Database. Differences in disease presentation and likelihood of guideline-concordant surgical management (total thyroidectomy and resection of ≥1 lymph node) were assessed by sex and race/ethnicity. RESULTS: Of 6154 patients, 68.2% underwent guideline-concordant surgery. Tumors >4 â€‹cm were more likely in men (vs. women: OR 2.47, p â€‹< â€‹0.001) and Hispanic patients (vs. White patients: OR 1.52, p â€‹= â€‹0.001). Non-White patients were more likely to have distant metastases (Black: OR 1.63, p â€‹= â€‹0.002; Hispanic: OR 1.44, p â€‹= â€‹0.038) and experienced longer time to surgery (Black: HR 0.66, p â€‹< â€‹0.001; Hispanic: HR 0.71, p â€‹< â€‹0.001). Black patients were less likely to undergo guideline-concordant surgery (OR 0.70, p â€‹= â€‹0.022). CONCLUSIONS: Male and non-White patients with MTC more frequently present with advanced disease, and Black patients are less likely to undergo guideline-concordant surgery.

Unveiling Variations: A Comprehensive Comparison of Five Globally Used Thyroid Cytology Reporting Systems With Histopathological Correlation.

Introduction Accurate cytological assessment is pivotal for managing thyroid lesions and various global reporting systems are in use, such as the globally acclaimed The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC), alongside other reporting systems namely, the Japanese Reporting System for Thyroid Aspiration Cytology (JRSTAC), Italian Consensus for the Classification and Reporting of Thyroid Cytology (ICCRTC), the UK Royal College of Pathologists System for Reporting Thyroid Cytopathology (UK RCPath), the Royal College of Pathologists of Australasia and Australian Society of Cytology Classification System (RCPA/ASC). Notably, variations exist among these systems which are influenced by country-specific statistics. Given the lack of large-scale data in India and the difference in prevalence of diagnostic entities compared to the western population, this study aimed to identify reporting systems suitable for the Indian population focusing on distinguishing neoplastic from non-neoplastic lesions. Materials and methods A cross-sectional analysis of 40 thyroid cytology cases with histopathological correlation was conducted. Pathologists independently assessed cytology slides using JRSTAC, ICCRTC, RCPA/ASC, UK RCPath and TBSRTC. Five performance indicators, sensitivity, specificity, positive predictive value (PPV) of neoplastic conditions, negative predictive value (NPV) of non-neoplastic conditions, diagnostic accuracy and two quality indicators, percentage of Atypia of undetermined significance (AUS) and AUS/Malignant ratio were analyzed and compared. Results Among 40 cases, 22 cases were neoplastic (16 papillary thyroid carcinoma, six follicular adenoma) and 18 non-neoplastic (14 multinodular goiter, four lymphocytic thyroiditis). Specific patterns emerged in cases labeled "Non-diagnostic", prompted questions about categorizing inadequately cellular cases as "benign" in light of the presence of specific findings. All reporting systems showed 100% specificity in detecting non-neoplastic and neoplastic conditions in Category 1 and Category 6 respectively. Performance and quality indicators varied among reporting systems with TBSRTC (PPV of neoplastic cases 85.71%, NPV of non-neoplastic cases 70.58%, specificity 85.7%, sensitivity 70.58%, diagnostic accuracy 60%, AUS percentage 22.5% and AUS/Malignant ratio 3%) and RCPA/ASC (PPV of neoplastic cases 76.47%, NPV of non-neoplastic cases 70.58%, specificity 75%, sensitivity 72.2%, diagnostic accuracy 62.5%, AUS percentage 15% and AUS/Malignant ratio 3%) showing better results. Conclusion Among the five thyroid cytology reporting systems studied, TBSRTC and RCPA/ASC showed better overall performance results and quality indicators were close to benchmark. Better performance by TBSRTC 2023 could be due to the detailed criterion mentioned per category with subcategorization of AUS and suspicious for malignancy by features of cytological and architectural atypia. Similarly, RCPA/ASC has subcategorized AUS with defined criteria and certain background features were included as an isolated criterion for the suspicious for malignancy category. These defined criteria outlined in TBSRTC and RCPA/ASC played a crucial role in minimizing and reclassifying cases from the indeterminate categories (AUS and suspicious for malignancy) into well-defined categories with established management protocols.

Clinical and Histopathological Risk Factors for Radioactive Iodine Refractory Follicular and Oncocytic Thyroid Carcinoma.

INTRODUCTION: Risk factors for radioactive iodine (RAI)-refractory disease in follicular (FTC) and oncocytic thyroid carcinoma (OTC) are unknown. Therefore, 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. 2015 ATA Guidelines were used to define RAI-refractory disease. An extensive histopathological revision was performed applying the 2022 WHO Classification using Palga: Dutch Pathology Databank. Logistic regression was used to identify risk factors for RAI-refractory disease, stratified for histological subtype. RESULTS: Ninety FTC and 52 OTC patients were included, of which 14 FTC (15.6%) and 22 OTC (42.3%) 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 [IQR: 1.0-2.0] vs 2.5 [IQR: 2.0-3.75]), and it substantially decreased the 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 extra-thyroidal 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.

Malignancy risk stratification and subcategorization of K-TIRADS intermediate suspicion thyroid nodules: a retrospective multicenter study.

PURPOSE: This study aimed to develop the ultrasonography (US) criteria for risk stratification of the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) 4 nodules, and to evaluate the diagnostic yield of a modified biopsy criterion in a multicenter cohort. METHODS: In total, 1,542 K-TIRADS 4 nodules (≥1 cm) were included in the study. US criteria for the subcategorization of K-TIRADS 4 nodules were developed based on high-risk US features. The diagnostic yields and false referral rates of biopsy criterion 1 (size cut-off of 1 cm), biopsy criterion 2 (size cut-off of 1.5 cm), and modified biopsy criterion 3 (size cut-off of 1 cm for K-TIRADS 4B and 1.5 cm for K-TIRADS 4A) were evaluated. RESULTS: The five high-risk US features (solid composition, marked hypoechogenicity, macrocalcification, punctate echogenic foci, and irregular margin) independently increased the malignancy risk of the K-TIRADS 4 nodules (P<0.001). The K-TIRADS 4 nodules could be subcategorized into higher- and lower-risk subcategories according to the number of high-risk US features: K-TIRADS 4B (≥2 US features) and K-TIRADS 4A (≤1 US feature). The modified biopsy criterion increased the diagnostic yield by 7.8% compared with criterion 2 and reduced the false referral rate by 15.3% compared with criterion 1 (P<0.001). CONCLUSION: The K-TIRADS 4 nodules were subcategorized as K-TIRADS 4B and K-TIRADS 4A based on high-risk US features. The modified biopsy criterion 3 showed a similar diagnostic yield and reduced false referral rate compared to criterion 1.

Knot-and-ear sign: a pathognomonic ultrasonographic feature of suture granuloma after thyroid surgery.

PURPOSE: This study investigated the clinical and ultrasonographic (US) findings of suture granulomas and recurrent tumors, and aimed to identify specific characteristics of suture granulomas through an experimental study. METHODS: This retrospective study included 20 pathologically confirmed suture granulomas and 40 recurrent tumors between January 2010 and December 2020. The clinical findings included suture material, surgery, and initial TNM stage. The US findings included shape, size, margin, echogenicity, heterogeneity, vascularity, and internal echogenic foci. The distribution, paired appearance, and "knot-and-ear" appearance of internal echogenic foci were assessed. An experiment using pork meat investigated the US configuration of suture knots. RESULTS: Eighteen patients with 20 suture granulomas (15 women; mean age, 52±13 years) and 37 patients with 40 recurrent tumors (24 women; 54±18 years) were included. Patients with suture granulomas exhibited earlier initial T and N stages than those with recurrent tumors. The knot-and-ear appearance, defined as an echogenic dot accompanied by two adjacent echogenic dots or lines based on experimental findings, was observed in 50% of suture granulomas, but not in recurrent tumors (P<0.001). Central internal echogenic foci (68.8%, P=0.023) and paired appearance (75.0%, P<0.001) were more frequent in suture granulomas. During follow-up, 94.1% of suture granulomas shrunk. CONCLUSION: The knot-and-ear appearance is a potential pathognomonic finding of suture granuloma, and central internal echogenic foci with paired appearance were typical US features. Clinically, suture granulomas showed early T and N stages and size reduction during follow-up. Understanding these features can prevent unnecessary biopsy or diagnostic surgery.

Genotype-Phenotype Correlations in Thirty Japanese Patients with Congenital Hypothyroidism Attributable to TG Defects.

CONTEXT: Thyroglobulin (Tg), encoded by TG, is essential for thyroid hormone synthesis. TG defects result in congenital hypothyroidism (CH). Most reported patients were born before the introduction of newborn screening (NBS). OBJECTIVE: We aimed to clarify the phenotypic features of patients with TG defects diagnosed and treated since the neonatal period. SUBJECTS AND METHODS: We screened 1061 patients with CH for thirteen CH-related genes and identified thirty patients with TG defects. One patient was diagnosed due to hypothyroidism-related symptoms and the rest were diagnosed via NBS. Patients were divided into two groups according to their genotypes, and clinical characteristics were compared. We evaluated the functionality of the seven missense variants using HEK293 cells. RESULTS: Twenty-seven rare TG variants were detected, including fifteen nonsense, three frameshift, two splice-site, and seven missense variants. Patients were divided into two groups: thirteen patients with biallelic truncating variants and seventeen patients with monoallelic/biallelic missense variants. Patients with missense variants were more likely to develop thyroid enlargement with TSH stimulation than patients with biallelic truncating variants. Patients with biallelic truncating variants invariably required full hormone replacement, whereas patients with missense variants required variable doses of levothyroxine. Loss of function of the seven missense variants was confirmed in vitro. CONCLUSION: To our knowledge, this is the largest investigation on the clinical presentation of TG defects diagnosed in the neonatal period. Patients with missense variants showed relatively mild hypothyroidism with compensative goiter. Patients with only truncating variants showed minimal or no compensative goiter and required full hormone replacement.

Hashimoto Thyroiditis and Mortality in Patients with Differentiated Thyroid Cancer: The National Epidemiologic Survey of Thyroid Cancer in Korea and Meta-Analysis.

BACKGRUOUND: Many studies have shown that Hashimoto's thyroiditis (HT) acts as a protective factor in differentiated thyroid cancer (DTC), but little is known about its effects on mortality. Therefore, this study was performed to reveal the prognosis of HT on mortality in patients with DTC. METHODS: This study included two types of research. RESULTS: retrospective cohort study using the National Epidemiologic Survey of Thyroid cancer (NEST) in Korea and meta-analysis study with the NEST data and eight selected studies. RESULTS: Of the 4,398 patients with DTC in NEST, 341 patients (7.8%) died during the median follow-up period of 15 years (interquartile range, 12.3 to 15.6). Of these, 91 deaths (2.1%) were related to DTC. HT was associated with a smaller tumor size and less aggressive DTC. In Cox regression analysis after adjusting for age and sex, patients with HT showed a significantly lower risk of all-cause death (hazard ratio [HR], 0.71; 95% confidence interval [CI], 0.52 to 0.96) and DTC-related death (HR, 0.33; 95% CI, 0.14 to 0.77). The analysis with inverse probability of treatment weight data adjusted for age, sex, and year of thyroid cancer registration showed similar association. The meta-analysis showed that patients with HT showed a lower risk of all-cause mortality (risk ratio [RR], 0.24; 95% CI, 0.13 to 0.47) and thyroid cancer-related mortality (RR, 0.23; 95% CI, 0.13 to 0.40) in comparison with patients without HT. CONCLUSION: This study showed that DTC co-presenting with HT is associated with a low risk of advanced DTC and presents a low risk for all-cause and DTC-related death.

Surgical safety and effectiveness of bilateral axillo-breast approach robotic thyroidectomy: a systematic review and meta-analysis.

OBJECTIVES: To assess the safety and effectiveness of bilateral axillo-breast approach robotic thyroidectomy in thyroid tumor. METHODS: Bilateral axillo-breast approach robotic thyroidectomy and other approaches (open thyroidectomy, transoral robotic thyroidectomy, and bilateral axillo-breast approach endoscopic thyroidectomy) were compared in studies from 6 databases. RESULTS: Twenty-two studies (8830 individuals) were included. Bilateral axillo-breast approach robotic thyroidectomy had longer operation time, greater cosmetic satisfaction, and reduced transient hypoparathyroidism than conventional open thyroidectomy. Compared to bilateral axillo-breast approach endoscopic thyroidectomy, bilateral axillo-breast approach robotic thyroidectomy had greater amount of drainage, lower chances of transient vocal cord palsy and permanent hypothyroidism, and better surgical completeness (postopertive thyroblobulin level and lymph node removal). Bilateral axillo-breast approach robotic thyroidectomy induced greater postoperative drainage and greater patient dissatisfaction than transoral robotic thyroidectomy. CONCLUSION: Bilateral axillo-breast approach robotic thyroidectomy is inferior to transoral robotic thyroidectomy in drainage and cosmetic satisfaction but superior to bilateral axillo-breast approach endoscopic thyroidectomy in surgical performance. Its operation time is longer, but its cosmetic satisfaction is higher than open thyroidectomy.