Bethesda Categorization of Thyroid Nodule Cytology and Prediction of Thyroid Cancer Type and Prognosis

In-Office Management of Thyroid Nodules

Advancements in managing thyroid nodules are discussed, emphasizing in-office procedures as alternatives to traditional surgery. Thyroid nodules are prevalent, often benign, but some require further evaluation owing to malignancy concerns. Ultrasonography is the preferred method for evaluation, offering insights without radiation exposure. Nonsurgical interventions provide effective management options. Radiofrequency ablation reduces nodule size and symptoms with minimal complications and is performed in an outpatient setting, offering a cost-effective, quick recovery alternative to surgery. Proper training in ultrasound-guided procedures and careful patient selection are crucial for successful implementation. Minimally invasive techniques revolutionize thyroid nodule management, offering effective results with fewer complications.

Global, regional, and national burden of thyroid cancer in young people aged 10-24 years from 1990 to 2021: an analysis based on the Global Burden of Disease Study 2021

BACKGROUND

The burden of thyroid cancer (TC) among young people aged 10-24 years has not been systematically studied to date. This study aims to analyze the burden of TC among young people aged 10-24 years globally, regionally, and nationally from 1990 to 2021.

METHODS

We collected data on the incidence, mortality, and disability-adjusted life years (DALYs) rates for TC among young people aged 10-24 years from 1990 to 2021 using the Global Burden of Disease (GBD) 2021. Joinpoint regression analysis, frontier analysis, and health inequality analysis were employed to examine the variations and changes in TC burden among young people aged 10-24 years across different countries and regions.

RESULTS

From 1990 to 2021, the global burden of TC among young people has increased from 2.726 per 100,000 people [95% Uncertainty Interval (UI) 2.38-3.181] to 2.956 per 100,000 people (95% UI: 2.339-3.922), with an Average Annual Percent Change (AAPC) of 0.258 (95% Confidence Interval (CI): 0.138-0.378). The highest incidence rates were observed in Saudi Arabia, Taiwan (China), and Vietnam, while the highest mortality rates were in India, China, and Bangladesh. Frontier analysis revealed that the largest disparities in effective differences were found in the Netherlands, Germany, Canada, the United States of America, and Guinea-Bissau. The Slope Index of Inequality (SII) for DALYs increased slightly from -0.15 in 1990 to -1.3 in 2021.

CONCLUSIONS

Over the past three decades, the burden of TC has increased globally among young people, particularly in poorer countries and regions. This study highlights the importance of formulating public health policies tailored to the specific circumstances of different countries and regions aimed at reducing the TC burden among young people.

Beyond Malignancy Risk Stratification: FNAC Report Anticipates Thyroid Cancer Staging. Insights From Recent Studies

Fine-needle-aspiration-cytology (FNAC) is safe and cost-effective procedure for evaluating thyroid nodules. The non-negligible rate of indeterminate thyroid nodule (ITN) cytology warrants diagnostic surgery for histological assessment, in some cases. Two recent studies (from Europe and the United States) reported that the clinical behavior of a histologically proven thyroid cancer (TC) varies according to its presurgical FNAC results. Despite differences in study design, inclusion criteria, and the use of different cytology classification systems (Italian and Bethesda), the overall results were comparable. In order to further discuss these results and to provide additional perspective on the topic, the senior authors of the 2 studies invited other thyroid experts and cytologists not involved in the previous studies to participate in the present commentary. The strong, consistent clinical message that emerges, especially regarding PTC, is that TC with an initial diagnosis of ITN has a less aggressive clinical presentation, lower rates of (1) lymph node metastasis; (2) more aggressive variants; and (3) BRAFV600E mutations compared with differentiated thyroid cancer (DTC) with an initial diagnosis of "suspicious for malignancy" or "malignant." These results were consistent in both studies and strongly point toward a more indolent clinical phenotype of DTC with a preoperative diagnosis of ITN as opposed to suspicious for malignancy or malignant. Further understanding the clinical implications of these data appears of clinical relevance and will be discussed from both the endocrinologist and the cytologist point of view. The here overviewed data provide the foundation for beginning to examine the impact of less aggressive therapies for TC with an initial ITN diagnosis.

Expression of integrin α4β1 and α4β7 on B cells correlates with autoimmune responses in Graves' disease

BACKGROUND

Integrins are upregulated on endothelial cells and T-lymphocytes in autoimmune thyroid disease (AITD), potentially contributing to immune response localization. The role of integrins on B-cells in AITD remains unclear.

METHODS

Peripheral blood samples were collected from healthy controls (n = 56), patients with Graves' disease (GD) (n = 37) and Hashimoto's thyroiditis (HT) (n = 52). Ultrasound-guided fine-needle aspiration (FNA) of the thyroid was performed in patients with non-autoimmune thyroid disease (nAITD) (n = 19), GD (n = 11), and HT (n = 40). Integrins α4β7, α4β1, and αEβ7 in B cells were measured by flow cytometry. Serum zonulin levels were quantified via ELISA. Associations of integrins on B cells with thyroid hormones, thyroid autoantibodies, AITD duration, and zonulin were analyzed.

RESULTS

HT patients exhibited lower α4β7 and higher α4β1 expression on B cells compared to healthy controls and GD patients. While α4β7 was predominant on circulating B cells, the dominant integrin expressed on intrathyroidal B cells varied with specific thyroid diseases. In GD patients, α4β7 and α4β1 expression on circulating B cells correlated positively and negatively with thyroid function and thyroid stimulating immunoglobulins (TSI) levels, respectively. Intrathyroidal α4β1+ B cells positively correlated with TSH levels in HT patients. Additionally, serum zonulin was elevated in HT patients, and intrathyroidal α4β7+ B cells and α4β1+ B cells correlated negatively and positively with zonulin levels, respectively. Integrin αEβ7 on B cells showed no significant association with AITD.

CONCLUSION

Integrins expressed on B cells potentially play a role in the pathogenesis of AITD and might serve as immune biomarkers for the disease.

Temporal trends of thyroid cancer in China and globally from 1990 to 2021: an analysis of the global burden of Disease Study 2021

The incidence of thyroid cancer (TC) is increasing annually worldwide, with a growing burden. This study aims to analyze temporal trends in the burden of TC by age and sex in China and globally from 1990 to 2021, including incidence, prevalence, mortality, and disability-adjusted life years (DALYs) rates, and to predict future trends. We obtained data on TC in China and globally from 1990 to 2021 from the Global Burden of Disease (GBD) database. Using the Joinpoint regression model, we calculated and analyzed the trends in age-standardized incidence rate (ASIR), age-standardized prevalence rate (ASPR), age-standardized mortality rate (ASMR), and age-standardized DALYs rate (ASDR). Specifically, we estimated the annual percent change (APC), the average annual percent change (AAPC), and the corresponding 95% confidence intervals (95% CI) for each metric. Additionally, we conducted a decomposition analysis to investigate the impact of aging, population growth, and epidemiological factors on the incidence and mortality rates of TC. Furthermore, the autoregressive integrated moving average (ARIMA) model was employed to predict the burden of TC from 2022 to 2036.  From 1990 to 2021, the ASIR for TC in China increased from 1.249 (95% uncertainty interval [UI]: 1.009-1.473) per 100,000 to 2.473 (95% UI: 1.993-3.088) per 100,000. Conversely, the ASMR decreased from 0.473 (95% UI: 0.403-0.550) per 100,000 to 0.387 (95% UI: 0.307-0.472) per 100,000. Both males and females demonstrated an upward trajectory in ASIR. However, while the ASMR for females decreased, that for males showed an overall increase despite a decline in the last decade. The age of peak onset for TC ranged from 30 to 79 years, whereas the age of peak mortality was between 50 and 89 years. The analysis using the AAPC indicates that the growth in the ASIR (AAPC = 2.242, 95% CI: 2.112-2.371) and ASPR (AAPC = 2.975, 95% CI: 2.833-3.117) in China exceeds the global rate. Furthermore, the reduction in ASMR (AAPC = -0.651, 95% CI: -0.824 - -0.479) and ASDR (AAPC = -0.590, 95% CI: -0.787 - -0.392) in China is also more pronounced than globally. Decomposition analysis indicates that the increasing TC burden in China is primarily driven by population aging, whereas globally, population growth plays a more significant role. Projections based on predictive models suggest that from 2021 to 2036, the ASIR for both China and the global population is expected to continue rising, while the ASMR is anticipated to decline further.  The incidence rates of TC in China and globally have shown a continuous upward trend, which is expected to persist over the next 15 years. Additionally, although the number of male TC cases is relatively lower compared to females, the overall ASMR and ASDR for males have shown an upward trend, despite a slight decline in recent years. This highlights the need to enhance prevention, diagnosis, and treatment measures, and to develop differentiated screening and treatment strategies based on age and sex.

The sensitivity and specificity of fine needle aspiration cytology in detecting thyroid malignancy according to Bethesda system at a teaching hospital in Saudi Arabia

Background

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) aims to standardize the terminology and morphologic criteria associated with thyroid fine-needle aspiration cytology (FNAC) results while also providing corresponding risk assessments for malignancy. contributing to more consistent and standardized reporting of thyroid nodules and aiding clinicians in making informed decisions. Since then, it has been undergoing revisions and updates to further improve its utility and accuracy.

Materials and Methods

This is a retrospective study conducted at a tertiary care center. All patients with a history of thyroid gland swelling who had previously undergone FNA were included. The procedure included cytopathologists performing FNAC for all cases of midline neck swelling. Demographic and histopathology data were correlated with the cytological diagnosis.

Results

We included 288 cases. Of those, 234 (81.3%) were female and 54 (18.8%) were male. The presentation age range was 18-91 years. The most reported category was benign, which constituted 30.9% of the cases followed by malignancy (27.1%). As for thyroid lesions, papillary carcinoma was the most prevalent (43.6%). The correlation on cyto-histopathology was presented in every diagnostic category, showing high heterogeneity in diagnostic specificity and sensitivity. The overall diagnostic specificity and sensitivity were 56.05% (95% confidence interval [CI]: 47.92-63.95%) and 80.92% (95% CI: 73.13-87.25%), respectively. Positive and negative predictive values were 60.57% and 77.88%, respectively.

Conclusion

Our data suggests that the TBSRTC system promotes similar sensitivity and specificity to those reported elsewhere. It standardizes reporting and improves communication between cytopathologists and clinicians.

Autoimmune Thyroid Disease and Differentiated Thyroid Carcinoma: A Review of the Mechanisms That Explain an Intriguing and Exciting Relationship

Autoimmune thyroid disease is a complex and highly frequent disease, where a wide variety of genetic, epigenetic and environmental factors (among others) come together and interact, and is characterized by the presence of two clinical outcomes: hypothyroidism (in Hashimoto's thyroiditis) and hyperthyroidism (in Graves-Basedow disease). For its part, differentiated thyroid carcinoma (mainly papillary carcinoma) is the most common type of cancer affecting the thyroid (and one of the most prevalent worldwide). An important co-occurrence between autoimmune thyroid disease and differentiated thyroid carcinoma has been documented. In this article, studies that have evaluated possible associations and relationships between autoimmune thyroid disease and differentiated thyroid cancer are systematically described and summarized. To date, the underlying mechanism that explains this association is inflammation; however, the characteristics and designs of the studies evaluated do not yet allow a causal relationship between the two entities to be established. These aspects have made it difficult to establish "causality" in the continuum of the pathogenesis between both conditions.

Early Post-operative Stimulated Serum Thyroglobulin: Role in Preventing Unnecessary Radioactive Iodine Treatment in Low to Intermediate Risk Papillary Thyroid Cancer

AIM

The aims of the study are to evaluate the predictive value of early post-operative stimulated thyroglobulin (sTg) analysis on the recurrence risk, and to define a cut-off value that is related to recurrence risk in low to intermediate risk papillary thyroid cancer (PTC).

METHODS

This retrospective cohort study included individuals who were diagnosed with PTC aged 18 years or older and had been operated by experienced surgeons of a tertiary university hospital between the years 2011 and 2021. The American Thyroid Association thyroid cancer guidelines version 2015 was used as the risk stratification system. Early sTg measurement obtained at 3-4 weeks after surgery when TSH >30 µIU/mL. Data was collected from the hospital database. A total of 328 patients who had post-operative early sTg values with negative anti-Tg antibodies were included.

RESULTS

The median age was 44 years. Of the 328 patients, 223 (68%) were women. The median tumor diameter was 11 mm. One hundred ninety-one patients (58.2%) had low risk and 137 (41.8%) had intermediate risk for recurrent disease. Of the 328 patients, 4.0% had recurrent disease. In multivariate Cox regression, post-operative early sTg value [OR: 1.070 (1.038-1.116), P = .000], and the pre-operative malign cytology [OR: 1.483 (1.080-2.245), P = .042] were independent risk factors for recurrence. On the ROC curve analysis, the cut-off value of early sTg was 4.1 ng/mL for those with recurrent disease.

CONCLUSION

This study demonstrated that early sTg could predict recurrent disease in patients with low to intermediate risk PTC. A cut-off of 4.1 ng/mL was identified with a high negative predictive value.

Cytological and Ultrasound Features of Thyroid Nodules Correlate With Histotypes and Variants of Thyroid Carcinoma

CONTEXT

Prognosis is excellent for papillary thyroid carcinoma (PTC), noninvasive follicular thyroid neoplasia with papillary-like nuclear features (NIFT-P), and follicular thyroid carcinoma (FTC) but is poor for poorly differentiated thyroid carcinoma (PDTC) and anaplastic thyroid carcinoma (ATC). Among PTCs, the prognosis is more favorable for follicular (FV-PTC) and classic (CV-PTC) than for tall cell (TCV-PTC), and solid (SV-PTC) variants.

OBJECTIVE

To associate histotypes and variants of thyroid carcinoma with ultrasound and cytological features.

METHODS

Histology of 1018 benign tumors and 514 PTC (249 CV, 167 FV, 49 TC, 34 SV, and 15 other variants), 52 NIFT-P, 50 FTC, 11 PDTC, and 3 ATC was correlated with fine-needle aspiration biopsy categories (Italian classification: TIR1, TIR2, TIR3A, TIR3B, TIR4, and TIR5) and ultrasound features at the Endocrinology Unit, University Hospital of Pisa. In total, 1117 patients with thyroid nodule(s) who underwent thyroidectomy were included.

RESULTS

Of PTC, 36.3% had indeterminate cytology (TIR3A or TIR3B), 56.6% were suspicious for malignancy or malignant (TIR4 or TIR5); 84.0% FTC and 69.3% NIFT-P were TIR3A or TIR3B; 72.5% FV-PTC and 73.6% SV-PTC were TIR3A or TIR3B; 79.9% CV-PTC and 95.9% TCV-PTC were TIR4 or TIR5. The association of a hypoechoic pattern, irregular margins, and no microcalcifications was more frequent in TCV-PTC than in CV-PTC (P = .02, positive predictive value = 38.9%; negative predictive value = 85.5%).

CONCLUSION

At cytology, most FTC, NIFT-P, FV-PTC, and SV-PTC were indeterminate, most CV-PTC and TCV-PTC were suspicious for malignancy or malignant. Ultrasound can be helpful in ruling out TCV-PTC.

Diagnosis of thyroid nodules

Thyroid nodules are common, usually asymptomatic, and often pose minimal risk to the affected patient. However, 10-15% prove malignant and serve as the rationale for diagnostic assessment. Safely identifying and treating a relevant thyroid cancer through a cost-effective process is the primary goal of the treating practitioner. Ultrasound is the principal means of initial nodule assessment and should be performed when any thyroid nodule is suspected. Fine-needle aspiration provides further cytological determination of benign or malignant disease and is generally applied to nodules larger than 1-2 cm in diameter, on the basis of holistic risk assessment. The Bethesda System for Reporting Thyroid Cytopathology provides standardised terminology, which enhances communication among health-care providers and patients. Benign cytology is highly accurate, whereas indeterminate cytology could benefit from further application of molecular testing. The ultimate goal of diagnostic assessment of thyroid nodules is to accurately identify malignancy while avoiding overtreatment. Low-risk thyroid nodules can be safely monitored in many patients with minimal diagnostic intervention.

Thyroid Nodule Shape Independently Predicts Risk of Malignancy

CONTEXT

Predictive models of thyroid nodule cancer risk are presently based upon nodule composition, echogenicity, margins, and the presence of microcalcifications. Nodule shape has shown promise to be an additive factor helping determine the need for nodule biopsy.

OBJECTIVE

We sought to determine if calculation of a nodule's spherical shape independently associates with cancer risk.

METHODS

This prospective cohort study, conducted at a single large academic healthcare system in the United States, included patients with 1 or 2 clinically relevant thyroid nodules (predominantly solid and over 1 cm) presenting for diagnostic evaluation. Thyroid ultrasound, cytological evaluation with fine-needle biopsy, and/or histopathological examination on occasion of thyroid surgery were performed. We calculated the nodule's long to short ratio (spherical shape), and its association with tissue proven benign or malignant endpoints.

RESULTS

The long to short nodule ratio was significantly lower in malignant compared to benign nodules indicating greater risk of malignancy in more spherical nodules (1.63 ± 0.38 for malignant nodules vs 1.74 ± 0.47 for benign, P < 0.0001). The risk of malignancy continually increased as the long to short ratio approached a purely spherical ratio of 1.0 (ratio > 2.00, 14.6% cancer; ratio 1.51-2.00, 19.7%; ratio 1.00-1.50, 25.5%, P < 0.0001). In multiple regression analysis, younger age, male sex, and nodule's spherical shape were each independently associated with cancer risk.

CONCLUSION

The more a thyroid nodule is spherically shaped, as indicated by a long to short ratio approaching 1.0, the greater its risk of malignancy. This was independent of age, sex, and nodule size. Incorporating a nodule's sphericity in the risk stratification systems may improve individualized clinical decision making.

Down-regulation of miR-7-5p and miR-548ar-5p predicts malignancy in indeterminate thyroid nodules negative for BRAF and RAS mutations

PURPOSE

The value of molecular markers in refining preoperative risk assessment of indeterminate thyroid nodules is being widely investigated. MicroRNAs (miRNA) are emerging as promising biomarkers for diagnostic and prognostic purposes. The aim of this study is to identify miRNAs specifically deregulated in mutation-negative indeterminate thyroid nodules.

METHODS

Ninety-eight nodules preoperatively diagnosed as TIR 3A or TIR 3B with available histological diagnosis of follicular adenoma (FA), noninvasive follicular neoplasm with papillary-like nuclear features (NIFTP), and follicular variant papillary thyroid carcinoma (FV-PTC) have been retrospectively selected. Mutations in BRAF and RAS genes have been tested in all samples by real-time PCR; miRNAs were purified from cytology slides of 60 samples; expression analysis of 798 miRNAs was measured by the nCounter system.

RESULTS

Point mutations in BRAF and RAS genes were detected in 32 out of 98 nodules (32.7%), the majority of which in FV-PTCs. Differential expression of miRNA in wild-type nodules highlighted that two miRNAs, namely miR-7-5p and miR-548ar-5p, were downregulated in FV-PTCs compared to FAs. The combined expression of these miRNAs, tested by ROC analysis, showed an area under the curve of 0.79. Sensitivity and negative predictive value were high both in wild-type (93% and 92%, respectively) and in mutated nodules (94% and 85%, respectively).

CONCLUSION

The analysis of miR-7-5p and miR-548ar-5p expression in indeterminate thyroid nodules demonstrated a promising value in ruling out malignancy.

Is there a relationship between preoperative cytological diagnosis and evolution in patients with differentiated thyroid carcinoma? A retrospective study

Objective

Cytological analysis and Bethesda classification of thyroid nodules is the standard method of diagnosing differentiated thyroid carcinoma (DTC). However, even for nodules with a non-malignant cytological diagnosis, there is a not insignificant risk of cancer. There are doubts whether this lack of certainty would influence patient prognosis. Our aim was to compare patients with DTC, classified according to the preoperative cytological diagnosis, regarding their evolution.

Methods

A retrospective study was carried out with 108 DTC patients submitted to total thyroidectomy (TT) between 2009 and 2015, divided into three groups according to preoperative cytological diagnosis (Bethesda classification): classes I/II, III/IV, and V/VI. Groups were compared for evolution considering response to treatment at last evaluation as well as time disease free. Statistical analysis used ANOVA, chi squared, and Kaplan-Meier curves with p<0.05 considered significant.

Results

Groups differed for time between nodule puncture and TT [in months; V/VI (2.35 ± 2.48) < III/IV (7.32 ± 6.34) < I/II (13.36 ± 8.9); p < 0.0001]. There was no significant difference between groups for evolution at final evaluation (disease free status; classes I/II: 71.4%; classes III/IV: 60%; classes V/VI: 66.6%; p = 0.7433), as well as time disease free (in months; classes I/II: 34.57 ± 25.82; classes III/IV: 38.04 ± 26.66; classes V/VI: 30.84 ± 26.34; p = 0.3841).

Conclusion

DTC patients classified according to preoperative cytological diagnosis did not differ for evolution. Although patients with non-malignant cytological diagnoses were submitted to TT later, this did not affect the evolution of the cases.

Clinical Factors Predictive of Lymph Node Metastasis in Thyroid Cancer Patients: A Multivariate Analysis

BACKGROUND

Early-stage thyroid cancers have excellent survival. However, lymph node metastases (LNM) confer a worse prognosis and are not always known preoperatively. Therefore, investigation on the clinical and histological factors predictive of LNM in thyroid cancers was conducted to tailor the extent of surgery and radioactive iodine therapy.

STUDY DESIGN

Multivariate logistic regressions were performed based on retrospective data from thyroid cancer patients seen between 2013 and 2020 at a single institution.

RESULTS

Among 913 patients, mean age was 49.4 years, 76.5% were female, 58.3% were White, 21.2% were Black, and 27.9% had LNM. In the multivariate analyses in which the outcome was LNM, White (odds ratio [OR] 1.74, 95% CI 0.98 to 3.15, p = 0.064) and Hispanic patients (OR 2.36, 95% CI 0.97 to 5.77, p = 0.059) trended toward higher risk of LNM compared to Black patients, whereas age (OR 0.98, 95% CI 0.97 to 1.00, p = 0.008) showed protective effect. Tumor size (OR 1.04, 95% CI 1.01 to 1.07, p = 0.007), extrathyroidal extension (OR 2.46, 95% CI 1.53 to 3.97, p < 0.001), lymphovascular invasion (OR 6.30, 95% CI 3.68 to 11.14, p < 0.001), and multifocality (OR 1.47, 95% CI 1.01 to 2.12, p = 0.042) were associated with higher risk of LNM. In another model with outcome as >5 LNM, tumor size (OR 1.07, 95% CI 1.03 to 1.11, p = 0.001), age (OR 0.95, 95% CI 0.93 to 0.97, p < 0.001), extrathyroidal extension (OR 3.20, 95% CI 1.83 to 5.61, p < 0.001), and lymphovascular invasion (OR 6.82, 95% CI 3.87 to 12.17, p < 0.001) remained significant predictors.

CONCLUSION

Our analyses demonstrated and confirmed that age, tumor size, extrathyroidal extension, and lymphovascular invasion are independent predictors of significant LNM, thereby conferring higher risk of recurrence. Risk of LNM based on these patient characteristics should be considered when planning an operative approach.

The Autoantibodies against Tumor-Associated Antigens as Potential Blood-Based Biomarkers in Thyroid Neoplasia: Rationales, Opportunities and Challenges

The Autoantibodies targeting Tumor-Associated Antigens (TAA-AAbs) emerge as a result of a variety of tumor-related immunogenic stimuli and may be regarded as the eyewitnesses to the anti-tumor immune response. TAA-AAbs may be readily detected in peripheral blood to unveil the presence of a particular TAA-expressing tumor, and a fair number of TAAs eliciting the tumor-associated autoantibody response have been identified. The potential of TAA-AAbs as tumor biomarkers has been extensively studied in many human malignancies with a major influence on public health; however, tumors of the endocrine system, and, in particular, the well-differentiated follicular cell-derived thyroid neoplasms, remain understudied in this context. This review provides a detailed perspective on and legitimate rationales for the potential use of TAA-AAbs in thyroid neoplasia, with particular reference to the already established diagnostic implications of the TAA-AAbs in human cancer, to the windows for improvement and diagnostic niches in the current workup strategies in nodular thyroid disease and differentiated thyroid cancer that TAA-AAbs may successfully occupy, as well as to the proof-of-concept studies demonstrating the usefulness of TAA-AAbs in thyroid oncology, particularly for the pre-surgical discrimination between tumors of different malignant potential in the context of the indeterminate results of the fine-needle aspiration cytology.

The Frequency of Intrathyroidal Follicular Helper T Cells Varies with the Progression of Graves’ Disease and Hashimoto’s Thyroiditis

Objective

Autoimmune thyroid diseases (AITD), mainly Graves' disease (GD) and Hashimoto's thyroiditis (HT), are common organ-specific autoimmune diseases characterized by circulating antibodies and lymphocyte infiltration. Follicular helper T (Tfh) cell dysregulation is involved in the development of autoimmune pathologies. We aimed to explore the role of intrathyroidal and circulating Tfh cells in patients with GD and HT.

Methods

Ultrasound-guided thyroid fine-needle aspiration (FNA) was conducted in 35 patients with GD, 40 patients with HT, and 22 patients with nonautoimmune thyroid disease (nAITD). Peripheral blood samples were also obtained from 40 patients with GD, 40 patients with HT, and 40 healthy controls. The frequencies of intrathyroidal and circulating Tfh cells from FNA and peripheral blood samples were assessed by flow cytometry. Additionally, the correlations between the frequencies of the Tfh cells and the levels of autoantibodies and hormones or disease duration were analyzed.

Results

The frequency of intrathyroidal CD4⁺CXCR5⁺ICOS^high Tfh cells was higher in HT patients than in GD patients. Significant correlations were identified between the percentages of circulating and intrathyroidal Tfh cells and the serum concentrations of thyroid autoantibodies, especially thyroglobulin antibodies (TgAb), in AITD. Intrathyroidal CD4⁺CXCR5⁺ICOS^high Tfh cells were positively correlated with free triiodothyronine (FT3) in HT patients but negatively correlated with FT3 in GD patients. In addition, HT patients with a longer disease duration had an increased frequency of intrathyroidal CD4⁺CXCR5⁺ICOS^high and CD4⁺CXCR5⁺PD-1⁺ Tfh cells. In contrast, in the GD patients, a longer disease duration did not affect the frequency of intrathyroidal CD4⁺CXCR5⁺ICOS^high but was associated with a lower frequency of CD4⁺CXCR5⁺PD-1⁺ Tfh cells.

Conclusions

Our data suggest that intrathyroidal Tfh cells might play a role in the pathogenesis of AITD and they are potential immunobiomarkers for AITD.

Positive Correlation of Thyroid Nodule Cytology with Molecular Profiling-a Single-Center Experience

Despite several reports on the association between molecular profiling, aggressive histology, and clinical outcomes, the association between mutation expression and pre-operative cytology is yet to be demonstrated. Therefore, we performed a retrospective, single-center study, including all patients who underwent molecular profiling of thyroid nodules in Bethesda System for Reporting Thyroid Cytopathology (BSRTC) categories III to VI, between 2018 and 2019. Medical records were reviewed to collect demographics, cytology results according to BSRTC, final pathology (presence of malignancy and its type, as well as presence of aggressive features, including extrathyroidal extension, positive neck lymph nodes, and multifocality), and the identified genetic variants stratified by risk levels, according to the 2015 ATA guidelines. We supplemented this analysis with a systematic review to identify the variant distributions across the literature. We included data on 55 nodules from 48 patients for the final analysis. A significant positive correlation was found between BSRTC categories and the mutation risk level, shown by an increase in the intermediate to high-risk mutation rate in the higher BSRTC categories (Rs = 0.660, p ≤ 0.001). A significant positive correlation was also found between mutation risk levels and the presence of malignancy and aggressive tumor features (Rs = 0.637, p < 0.001 and Rs = 0.459, p = 0.006, respectively). This novel positive and significant correlation between BSRTC categories and the mutation risk level provides additional insight to aid clinicians in the interpretation of BSRTC results and may contribute to the discussion of appropriate management of thyroid nodule with patients.

Cost-Effectiveness Analysis of Ultrasound Screening for Thyroid Cancer in Asymptomatic Adults

Objectives: This study evaluated the long-term cost-effectiveness of ultrasound screening for thyroid cancer compared with non-screening in asymptomatic adults. Methods: Applying a Markov decision-tree model with effectiveness and cost data from literature, we compared the long-term cost-effectiveness of the two strategies: ultrasound screening and non-screening for thyroid cancer. A one-way sensitivity analysis and a probabilistic sensitivity analysis were performed to verify the stability of model results. Results: The cumulative cost of screening for thyroid cancer was $18,819.24, with 18.74 quality-adjusted life years (QALYs), whereas the cumulative cost of non-screening was $15,864.28, with 18.71 QALYs. The incremental cost-effectiveness ratio of $106,947.50/QALY greatly exceeded the threshold of $50,000. The result of the one-way sensitivity analysis showed that the utility values of benign nodules and utility of health after thyroid cancer surgery would affect the results. Conclusions: Ultrasound screening for thyroid cancer has no obvious advantage in terms of cost-effectiveness compared with non-screening. The optimized thyroid screening strategy for a specific population is essential.

The evolution of "atypia" in thyroid fine-needle aspiration specimens

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) provided a standardized framework for resulting thyroid fine-needle aspiration (FNA) specimens and introduced the low-risk category of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS). This indeterminate category has significantly evolved over time with the incorporation of molecular testing, reclassification of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), and a shift toward more conservative management. Despite these refinements, AUS/FLUS remains a challenge, at both the diagnostic and therapeutic level. We review the criteria for AUS/FLUS and the associated controversies in rendering this diagnosis, while highlighting the importance of a multidisciplinary approach to managing atypical thyroid nodules.

The Value of Sonography in Distinguishing Follicular Thyroid Carcinoma from Adenoma

Purpose

Differentiation between follicular thyroid carcinomas (FTCs) and follicular thyroid adenomas (FTAs) is difficult and the sonographic features of FTC are not yet fully established. The purpose of this study is to explore the sonographic features of FTC and the value of sonography in differentiating FTCs from FTAs.

Patients and Methods

A total of 28 pathologically proven FTCs and 53 FTAs in 78 patients who were performed thyroid surgery were included in this retrospective study. The sonographic features of each tumor including an interrupted halo, satellite nodule(s) with or without halo ring, local irregularity of margin and cluster of grapes sign were evaluated. A mode image of FTC halo was built up in our study. The frequencies of the sonographic features were compared by chi-square test or Fisher exact test between FTCs and FTAs. The relative risk of malignancy was assessed by logistic regression analysis.

Results

Logistic regression analysis showed that a thick, irregular and/or interrupted halo with or without satellite nodule(s), hypoechoic or marked hypoechoic echogenicity, a predominantly solid pattern, cluster of grapes sign, micro-or macro-calcifications, rim calcifications correlated with significant increases in relative risk for FTCs (odds ratio 11.48 (1.37-96.56), 6.74 (1.05-43.30), 17.51 (1.78-172.53), 9.55 (1.44-63.46), 9.36 (1.25-70.15) and 17.45 (1.04-292.65), respectively, p<0.05). Two new sonographic features, an interrupted halo and satellite nodule(s) with or without halo ring, can only be found in FTCs.

Conclusion

An interrupted halo and satellite nodule(s) with or without halo ring are specific sonographic features for FTCs. Sonography could play a role in differentiating follicular thyroid carcinoma from adenoma.

Role of fine-needle aspiration cytology in evaluating thyroid nodules. A retrospective study from a tertiary care center of Western region, Saudi Arabia

OBJECTIVES

To evaluate the accuracy and e cacy of ne-needle aspiration cytology (FNAC) in diagnosing thyroid nodules, correlating it with the histopathological findings.

METHODS

A retrospective evaluation of 314 patients was undertaken at a tertiary referral center of King Abdullah Medical City (KAMC), Makkah, Kingdom of Saudi Arabia, between 2010-2019. Patients who presented with thyroid swellings underwent ultrasonography and FNAC. If indicated, surgery was performed. The FNAC findings were compared to the final histopathological reports.

RESULTS

The findings for FNAC from our data set of 314 patients showed a sensitivity value of 79.8%, specificity of 82.1%, accuracy of 74.8%, positive predictive value of 74.8%, and negative predictive value of 85.9%. Conclusion: Our study showed that FNAC has high sensitivity and speci city in the initial evaluation of patients with thyroid nodules. When guided by ultrasonography, the accuracy can be markedly improved. Molecular markers once widely available can improve the diagnostic power of FNAC to be no less than the histopathologic evaluation of thyroid tissue.

The Correlation of Age with Prognosis of Atypia of Undetermined Significance and Follicular Lesion of Undetermined Significance in Thyroid Nodules

Purpose

Although some prognostic variables and risk factors for thyroid cancer (TC) are age-related, the association between age and the risk of TC in patients with thyroid nodules (TNs) assigned to atypia of undetermined significance (AUS) and follicular lesion of undetermined significance (FLUS) is poorly estimated. The aim of this study was to assess the histopathology of AUS/FLUS and the risk of TC according to the age of the patients at the time of AUS/FLUS diagnosis.

Patients and Methods

Among 5021 individuals treated for TNs at one institution from 2008 to 2018, 161 (3.2%) patients with 161 TNs assigned to the AUS/FLUS category (1 nodule per patient) were selected and stratified by age at initial diagnosis: <55 years, 55–75 years and >75 years. Logistic regression analysis was used to estimate the association of age with the risk of TC diagnosis.

Results

Ninety-one (56.52%) patients <55 years old, 58 (36.02%) patients 55–75 years old, and 12 (7.45%) individuals >75 years old were identified. There were 130 (80.7%) females and 31 (19.3%) males with a mean age of 50.6 ± 16.12 years. Among the evaluated TNs, 142 (88.2%) were ultimately diagnosed as benign, and 19 (11.8%) were diagnosed as malignant. Younger age in patients was significantly related to malignancy outcome (p=0.024 for age <55 years). Patients aged 55–75 years had a significantly lower risk of TC than the other age categories (p=0.040). The risks of high vascularity and fast tumor growth were significantly higher in the youngest category than in the other categories (age <55 years old: p=0.045 and p=0.002, respectively).

Conclusion

Although patients with TNs classified as AUS/FLUS by ultrasound-guided fine needle aspiration biopsy (UG-FNAB) are not typically qualified for surgery, it is worth noting that younger patients with an AUS/FLUS diagnosis might be at a higher risk of TC.

Cytological Sub-Classification of Atypia of Undetermined Significance May Predict Malignancy Risk in Thyroid Nodules

BACKGROUND

Atypia/follicular lesion of undetermined significance (AUS/FLUS) carries a malignancy risk reaching up to 50%. Based on the reported malignancy rate in a given population, the clinical practice towards such a category varies. We hereby identify clinical parameters for risk stratification to aid in decision-making for either surgical referral or a clinical follow-up. Our aim is to identify clinical parameters that guided both clinicians and patients at our institutions to reach a clinical decision including atypia types.

METHODS

A retrospective review of patients with Bethesda III category thyroid nodules from tertiary centres in the Emirate of Abu Dhabi during January 2011 through December 2015 was carried out. Malignancy risk in Bethesda category III nodules and repeat FNA utility were calculated. Parameters that guided both clinicians and patients for appropriate referral to surgery were studied.

RESULTS

Two hundred and two cases were included in the study. Of these, 101 cases underwent surgery initially following the first FNA and 10 cases following FNA repeat. Histology confirmed malignancy in (41%) of cases that went initially to surgery and in (40%) of cases that underwent a repeat FNA. Repeat FNA resulted in 17 (44.74%) cases being re-classified into benign category, 10 (26.3%) being AUS/FLUS category, 6 (15.7%) being both suspicious and malignant, and 5 (13.16%) being unsatisfactory. Repeating FNA resulted in a definitive diagnostic utility in 50% of the cases. Eighty percent of malignant cases demonstrated nuclear atypia.

CONCLUSION

The relatively high malignancy rate in our institutions, the suspicious radiographic features, the atypia groups, and the repeat FNA predictive value stratified Bethesda III category nodules for proper malignancy prediction and appropriate management.

Indian experience of AUS/FLUS diagnosis: is it different from rest of Asia and the West?-A systematic review and meta-analysis

Background

Atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) is the most heterogeneous subcategory of the Bethesda system for thyroid cytopathology with laid down permissible limits of frequency and risk of malignancy (ROM). Due to differences in thyroid clinical practice worldwide, variations have been found in frequency, resection rates (RR) and ROM. Therefore, this systematic review and meta-analysis of AUS/FLUS across different regions was conducted and comparison of data from India was done with the rest of Asia and the West.

Methods

We searched PubMed and Google search engines from January 2009-Dec 2019 using terms "AUS Thyroid" and "FLUS Thyroid". Meta-analysis was performed using DerSimonian-Laird method and 95% confidence intervals were calculated using random effects model. Independent samples t-test was used to compare frequency, RR, and ROM of AUS/FLUS between India, rest of Asia and the West.

Results

Out of 15,000 studies on internet, 60 (18 Indian, 12 Asian and 30 Western) were included. Total aspirates were 201,657; 14,279 Indian, 62,448 Asian, 124,930 Western. Pooled estimates were: frequency 7.3% (6.3-8.3%), RR 41.9% (37.4-46.6%), ROM 33.3% (26.8-39.9%). Pooled prevalence of rate did not vary significantly across the three regions. Pooled prevalence of RR was highest in India (52.9%) and lowest in rest of Asia (26.5%); of ROM was highest in Asia (45.9%), lowest in the West (26.3%) (P<0.01). Statistical analysis demonstrated publication bias, limited to Indian and Western studies. Papillary thyroid carcinoma was the most common surgical diagnosis (87.9%; 1,082/1,231).

Conclusions

This meta-analysis showed differences in thyroid clinical practice followed in India, rest of Asia and the West. Although pooled prevalence of rate of AUS/FLUS was similar across the three, pooled RR and ROM varied. AUS/FLUS nodules were more frequently resected in Indian and Western studies than in rest of Asia. ROM was higher than recommended values in all three areas, being intermediate for India.

Are Bethesda III Thyroid Nodules More Aggressive than Bethesda IV Thyroid Nodules When Found to Be Malignant?

The Bethesda classification system for thyroid fine needle aspirate (FNA) is used to predict the risk of malignancy and to guide the management of thyroid nodules. We postulated that thyroid malignancies characterized as Bethesda III on FNA have more aggressive features than those classified as Bethesda IV. A retrospective chart review was performed to identify those who underwent thyroid surgery at a single tertiary hospital setting between 2015 and 2020. Associations between Bethesda category, molecular genetic test results, and histopathologic findings were examined. Out of 628 surgeries that were performed, 199 (54.2%) Bethesda III nodules and 216 (82.8%) Bethesda IV nodules were malignant. Of those that were malignant, 37 (18.6%) and 22 (10.2%) Bethesda III and Bethesda IV nodules showed aggressive features, respectively (p value = 0.014). There was a proportionally increased number of aggressive features in extra-thyroidal extension, lymph nodes metastasis, and all aggressive subtypes of papillary thyroid cancer in the Bethesda III category. Although Bethesda IV nodules are much more likely to be malignant (p value = 0.002), our study suggests that Bethesda III nodules that are resected are more likely to have aggressive features than Bethesda IV nodules, with a statistically significant increase in the solid variant of papillary thyroid cancer and lymph node metastasis.

Practice patterns for surgical management of low-risk papillary thyroid cancer from 2014 to 2019: A CESQIP analysis

BACKGROUND

Patients with low-risk-PTC who undergo thyroid lobectomy (TL) have comparable disease-specific survival with lower morbidity than total thyroidectomy (TT). We aim to describe the surgical management of low-risk-PTC using the Collaborative Endocrine Surgery Quality Improvement Program (CESQIP).

METHOD

CESQIP thyroidectomies of PTC tumors <4 cm were analyzed from 2014 to 2019 (n = 740). Postoperative outcomes were compared. Subgroup analysis examined temporal and institutional trends, and stratified for tumor size. Statistics utilized t-test, ANOVA, and Chi-squared.

RESULTS

TT patients had greater hypoparathyroidism, operative time, and length-of-stay (all p < 0.001). Incidence of TL decreased with increasing tumor size (24.2% for <1 cm, 15.8% for 1-2 cm, 6.1% for 2-4 cm). TL rates increased from 2.0% in 2014 to 21.2% in 2018-19. Completion thyroidectomy was recommended in 12.0% of TL subjects. There was significant variation in TL rate by institution (p < .001).

CONCLUSIONS

For low-risk-PTC, TT remained the most commonly utilized operation. TL rates increased following release of the new ATA guidelines. TT was associated with higher perioperative morbidity. Further insight is needed to understand factors influencing operative approach.

High risk of malignancy in cases with atypia of undetermined significance on fine needle aspiration of thyroid nodules even after exclusion of NIFTP

BACKGROUND

Fine needle aspiration cytopathology (FNAC) is the most reliable tool for evaluating thyroid nodules. However, diagnosing Bethesda category III, atypia/follicular lesion of undetermined significance (AUS/FLUS), is a major limitation. The aim of this study was to evaluate the risk of malignancy (RoM) in AUS/FLUS nodules. A systematic review was also carried out analyzing the largest series.

METHODS

Totally 1750 cases (9%) diagnosed with AUS/FLUS were evaluated retrospectively out of 19 392 cases within last 13 years. All patients undergoing surgery for AUS/FLUS were included into the study. Histopathology results were correlated; the impact of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) diagnosis on RoM is evaluated.

RESULTS

Of the 280 patients (16%) undergoing surgery, neoplasia were detected in 177 (RoN:63.2%) and malignancy in 119 (RoM:42.5%) of these neoplasia. Follicular variant of papillary thyroid carcinoma (FVPTC) was the commonest malignancy (55.5%). Additional 58 (20.7%) nodules were neoplastic, of which 26 (9.3%) were encapsulated follicular tumors with unknown malignancy potential (FT-UMP) and 32 (11.4%) were follicular adenomas. The remaining 103 patients (36.8%) had non-neoplastic nodules. After reevaluation of the encapsulated FVPTC cases, 20 of them were NIFTP and RoM dropped to 35.4% with a relative decrease of 16.7% and an absolute decrease of 7.1%.

CONCLUSION

In our series, 42.5% of nodules with AUS/FLUS were malignant; 63.2% of them were neoplastic. The RoM and RoN for AUS/FLUS nodules are still much higher than the revised expected RoM of international guidelines even after NIFTP cases excluded. Therefore, current recommendations should be reevaluated periodically in view of detailed clinicopathologic studies.

The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Thyroid Disease in Adults

OBJECTIVE

To develop evidence-based recommendations for safe, effective, and appropriate thyroidectomy.

BACKGROUND

Surgical management of thyroid disease has evolved considerably over several decades leading to variability in rendered care. Over 100,000 thyroid operations are performed annually in the US.

METHODS

The medical literature from 1/1/1985 to 11/9/2018 was reviewed by a panel of 19 experts in thyroid disorders representing multiple disciplines. The authors used the best available evidence to construct surgical management recommendations. Levels of evidence were determined using the American College of Physicians grading system, and management recommendations were discussed to consensus. Members of the American Association of Endocrine Surgeons reviewed and commented on preliminary drafts of the content.

RESULTS

These clinical guidelines analyze the indications for thyroidectomy as well as its definitions, technique, morbidity, and outcomes. Specific topics include Pathogenesis and Epidemiology, Initial Evaluation, Imaging, Fine Needle Aspiration Biopsy Diagnosis, Molecular Testing, Indications, Extent and Outcomes of Surgery, Preoperative Care, Initial Thyroidectomy, Perioperative Tissue Diagnosis, Nodal Dissection, Concurrent Parathyroidectomy, Hyperthyroid Conditions, Goiter, Adjuncts and Approaches to Thyroidectomy, Laryngology, Familial Thyroid Cancer, Postoperative Care and Complications, Cancer Management, and Reoperation.

CONCLUSIONS

Evidence-based guidelines were created to assist clinicians in the optimal surgical management of thyroid disease.

Thyroid nodules: diagnostic evaluation based on thyroid cancer risk assessment

Thyroid nodules are extremely common and can be detected by sensitive imaging in more than 60% of the general population. They are often identified in patients without symptoms who are undergoing evaluation for other medical complaints. Indiscriminate evaluation of thyroid nodules with thyroid biopsy could cause a harmful epidemic of diagnoses of thyroid cancer, but inadequate selection of thyroid nodules for biopsy can lead to missed diagnoses of clinically relevant thyroid cancer. Recent clinical guidelines advocate a more conservative approach in the evaluation of thyroid nodules based on risk assessment for thyroid cancer, as determined by clinical and ultrasound features to guide the need for biopsy. Moreover, newer evidence suggests that for patients with indeterminate thyroid biopsy results, a combined assessment including the initial ultrasound risk stratification or other ancillary testing (molecular markers, second opinion on thyroid cytology) can further clarify the risk of thyroid cancer and the management strategies. This review summarizes the clinical importance of adequate evaluation of thyroid nodules, focuses on the clinical evidence for diagnostic tests that can clarify the risk of thyroid cancer, and highlights the importance of considering the patient's values and preferences when deciding on management strategies in the setting of uncertainty about the risk of thyroid cancer.

Use of strain ultrasound elastography versus fine-needle aspiration cytology for the differential diagnosis of thyroid nodules: a retrospective analysis

OBJECTIVE

Fine-needle aspiration cytology is the risk stratification tool for thyroid nodules, and ultrasound elastography is not routinely used for the differential diagnosis of thyroid cancer. The current study aimed to compare the diagnostic parameters of ultrasound elastography and fine-needle aspiration cytology, using surgical pathology as the reference standard.

METHODS

In total, 205 patients with abnormal thyroid function test results underwent ultrasound-guided fine-needle aspiration cytology on the basis of the American College of Radiology Thyroid Imaging-Reporting and Data System classification and strain ultrasound elastography according to the ASTERIA criteria. Histopathological examination of the surgical specimens was performed according to the 2017 World Health Organization classification system. Moreover, a beneficial score analysis for each modality was conducted.

RESULTS

Of 265 nodules, 212 measured ≥1 cm. The strain index value increased from benign to malignant nodules, and the presence of autoimmune thyroid diseases did not affect the results (p>0.05 for all categories). The sensitivities of histopathological examination, ultrasound elastography, and fine-needle aspiration cytology for detection of nodules measuring ≥1 cm were 1, 1, and 0.97, respectively. The working area for detecting nodule(s) in a single image was similar between strain ultrasound elastography and fine-needle aspiration cytology for highly and moderately suspicious nodules. However, for mildly suspicious, unsuspicious, and benign nodules, the working area for detecting nodule(s) in a single image was higher in strain ultrasound elastography than in fine-needle aspiration cytology.

CONCLUSION

Strain ultrasound elastography for highly and moderately suspicious nodules facilitated the detection of mildly suspicious, unsuspicious, and benign nodules.

Conventional ultrasound characteristics, TI-RADS category and shear wave speed measurement between follicular adenoma and follicular thyroid carcinoma

The purpose of the study was to explore the differences of conventional ultrasound characteristics, thyroid imaging reporting and data system (TI-RADS) category and shear wave speed (SWS) measurement between follicular adenoma (FA) and follicular thyroid carcinoma (FTC). Twenty-eight FTCs and 67 FAs proven by surgery were retrospectively included for analysis. Conventional ultrasound and point-shear wave elastography (p-SWE) were performed in all of the included patients. The ultrasound features, American Thyroid Association (ATA) TI-RADS category and American College of Radiology (ACR) TI-RADS category, SWS measurement were compared between the two groups. Receiver operating characteristic (ROC) curve was performed and area under ROC curve (AUC) was obtained for significant features. There were no statistical differences in mean age (46.9±15.7years vs. 48.6±13.6years, P = 0.639), gender (9 males, 32.1% vs. 18 males, 29.0%, P = 0.766) and mean diameter (28.3±16.2 mm vs. 33.8±11.9 mm, P = 0.077) between FTCs and FAs. Hypoechogenicity, lobulated or irregular margin, macrocalcification were more common in FTCs than FAs (all P < 0.05). Mean SWS of FTCs (2.29±0.64 m/s) was slightly higher than that of FAs (1.94±0.68 m/s) (P = 0.023). The AUCs were 0.655, 0.744, and 0.744 with the cut-off SWS≥1.89 m/s, ACR TI-RADS category 4 and intermediate suspicion of ATA TI-RADS category. The sensitivity and AUC were 82.1% and 0.812 with combined ultrasound features of hypoechogenicity, lobulated or irregular margin and macrocalcification. In Conclusion, SWS measurement and TI-RADS categories were useful for the identification of FTCs from FAs.

Thyroid Nodules and Thyroid Cancer in the Pregnant Woman

Thyroid nodules and thyroid cancer are common conditions and may be identified during pregnancy. The comprehensive evaluation of thyroid nodules during pregnancy includes a medical history, physical examination, ultrasound assessment, and (when indicated) an ultrasound-guided fine-needle aspiration biopsy. Most thyroid cancers detected during pregnancy will not grow nor pose significant risk during gestation, and thyroid surgery in pregnant women poses higher risks than in nonpregnant women. Through a balanced and informed approach to the clinical care of this unique population, outcomes can be optimized for both the mother and the fetus.

Subcategorisation of AUS/FLUS thyroid lesions as per the 2017 Bethesda System for Reporting Thyroid Cytopathology: a retrospective study from a tertiary care centre analysing risk of malignancy (ROM) of the different subcategories

Aims

The 2017 Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) recommends subclassification of atypia of undetermined significance (AUS)/follicular lesion of undetermined significance (FLUS) into six subcategories. The present study evaluates the risk of malignancy (ROM) and risk of neoplasm (RON) among these.

Methods

All thyroid aspirates reported as AUS/FLUS over a 4.5-year period, with available histology, were reviewed and subclassified as per TBSRTC. ROM and RON were calculated and compared.

Results

Of 2554 thyroid aspirates, 281 (11.0%) were AUS/FLUS. Eighty-one with available histology were evaluated. ROM was 51.8%. Cytologic and architectural atypia (AUS-C&A) was the most prevalent (62.9%), followed by Hürthle cell type (19.6%), AUS-A (11.1%), AUS-not otherwise specified (NOS) (7.4%), cytologic atypia (AUS-C) (4.9%) and atypical lymphoid cells (1.2%). Papillary thyroid carcinoma (PTC) and adenomatous goitre (AG) were the most common histological diagnoses (27% each). On histology, AUS-C had 2/4 PTC and 2/4 AG on histology. AUS-A had 4/9 follicular neoplasm (FN) and 2/9 non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) while AUS C&A had 18/51 PTC, 13/51 AG, 11/51 NIFTP and 5/51 FN. ROM and RON were similar across subcategories, ROM was the highest for AUS-C&A (58.8%), AUS-C (50%) and AUS-NOS (50%). NIFTP reclassification as non-malignant reduced ROM to 35.8% (absolute reduction of 16% and a relative decrease of 31%) with the greatest relative decrease seen in AUS-A (50%), followed by AUS-C&A (37%), and none in others.

Conclusions

AUS/FLUS subcategorisation helped to indicate risk for the more likely neoplasm, whether PTC or FN. ROM was the highest for cases with cytological atypia but did not differ significantly across different subcategories. NIFTP changed the ROM of AUS-A and AUS-C&A, since both NIFTP and FN have microfollicles.

Comparison between ultrasonographic findings and fine needle aspiration cytology in differentiating malignant and benign thyroid nodules

The purpose of research was comparing the ultrasound (US) features and fine-needle aspiration cytology (FNAC) in detecting the thyroid nodules in clinical practice. A cross-sectional analytical study retrospectively reviewed the US and FNAC findings for a total of 170 thyroid nodules. The US features that we compared included echogenicity, calcifications, shape, halo and Doppler, between 2017 and 2018. Totally, 170 nodules of thyroid were studied, which contained 72 (42.4%) benign and 98 (57.6%) malignant thyroid nodules. The sonographic features were significantly associated with malignancy such as microcalcification (97.0%), hyperechogenicity (91.5%), wider than taller shape (98.0%), absent halo (90.9%) and positive Doppler (78.0%) (P < 0.01). The altogether accuracies of calcification, echogenicity, shape, halo, and Doppler were 0.96, 0.92, 0.97,0.82 and 0.82, respectively. Our data suggest that US features could be a good sonographic criterion for recommending FNA cytology with follow‐up thyroid sonography and FNA.

British Thyroid Association 2014 classification ultrasound scoring of thyroid nodules in predicting malignancy: Diagnostic performance and inter-observer agreement

Objectives

To assess the inter-observer agreement amongst five observers of differing levels of expertise in applying the British Thyroid Association (2014) guidelines for ultrasound scoring of thyroid nodules (BTA-U score) in the management of thyroid cancer, and to assess the U-score diagnostic performance in predicting malignancy.

Method

A total of 73 consecutive patients were included over a two-year period (July 2012 to July 2014), after referral to a tertiary head and neck oncology centre for ultrasound plus fine needle aspiration and cytology. Our five observers retrospectively and independently reviewed static ultrasound images on PACS and scored the thyroid nodules according to BTA-U classification. The observers were blinded to each other's scoring, cytology and histology results. Either the Kappa-statistic or intra-class correlation was used to assess the level of inter-observer agreement, plus agreement between the radiological and cytological diagnoses. The diagnostic performance of U-scoring for predicting final histological diagnosis was assessed with sensitivity, specificity, positive and negative predictive values.

Results

A Kappa-value of 0.73 (95% CI: 0.68-0.77) confirmed substantial inter-observer agreement amongst the five observers. All 17 histology confirmed malignant nodules were correctly classified as potentially malignant by all observers. The sensitivity and negative predictive value of BTA-U score in detecting and predicting malignancy were 100%, whereas the specificity and positive predictive values were 34% and 32%, respectively.

Conclusions

There is good inter-observer agreement in using the BTA-U score amongst different observers at differing levels of expertise. Adhering to BTA-U scoring can potentially achieve 100% sensitivity in selecting malignant nodules for sampling.

The role of prophylactic central compartment lymph node dissection in elderly patients with differentiated thyroid cancer: a multicentric study

BACKGROUND

Prophylactic central neck lymph-nodes dissection is still a topic of major debate in Literature. There is a lack of randomized controlled trials proving advantages in its application in terms of overall survival and local recurrence. Due to the recent rapid increase of elderly population, differentiated tumor carcinoma diagnosis increased in patients over 65 years old. The aim of this study was to compare recurrence rate, complications rate and histological features of tumors in elderly population.

METHODS

A retrospective study was carried out collecting data from 371 patients with differentiated thyroid cancer without clinical evidence of lymph-nodes involvement in three Italian referral centers from 2005 to 2015. All patients were aged ≥ 65 years and were divided in two groups based on the performed surgery (total thyroidectomy alone or associated with central lymph-nodes dissection). Moreover, patients were stratified according to the age between 65 and 74 years old and over 75 years old.

RESULTS

Total thyroidectomy alone was performed in 184 patients (group A) and total thyroidectomy with prophylactic central neck dissection was performed in 187 cases (group B). There was a statistically significant difference in complications between the groups in terms of neck hematoma (0.5% group A vs 3.7% group B), temporary hypoparathyroidism (11.4% group A vs 21.4% group B), and temporary unilateral recurrent nerve injury (1.5% group A vs 6.4% group B). Lymph nodes recurrence rate was 9.2% in group A and 8.5% in group B, with no statistically significant difference. There was a statistically significant difference in patients over 75 years old in terms of temporary hypoparathyroidism (24% group A vs 11% group B), permanent hypoparathyroidism (2,7% group A vs 0,3% group B) and recurrent nerve injury (9,5% group A vs 2% group B).

CONCLUSIONS

The role of prophylactic central neck dissection is still controversial, especially in elderly patients, and an aggressive surgical approach should be carefully evaluated. The Authors reported a similar low recurrence rate between total thyroidectomy and total thyroidectomy associated with prophylactic central neck dissection, with increased postoperative complications in the lymphadenectomy group and in patients over 75 years old, advocating a tailored surgical approach in elderly population.

Does the Bethesda category predict aggressive features in differentiated thyroid cancer?

OBJECTIVE

To analyze the importance of preoperative cytology of thyroid nodules and its relationship with mortality risk, recurrence risk, dynamic stratification, and aggressive characteristics (vascular invasion, aggressive histology, incomplete tumor resection, extrathyroidal extension of the tumor, and presence of lymph node and distant metastases).

SUBJECTS AND METHODS

Retrospective evaluation of 153 patients diagnosed with differentiated thyroid carcinoma (DTC) and following up at the Hospital Universitário Presidente Dutra between January 1999 and December 2016.

RESULTS

In all, 96% of the patients were female, 79.7% had papillary carcinoma and the most common fine-needle aspiration (FNA) result was Bethesda II (29.4%). The mean age was 43.11 ± 12.8 years. Overall, 85% of the patients progressed without any evidence of disease. There was a statistically significant relationship between the presurgical FNA and the presence of extrathyroidal extension, vascular invasion, and lymph node metastasis.

CONCLUSIONS

The preoperative cytology of the nodule may have an impact on the follow-up of patients with DTC. Future studies in a larger population are required to confirm this finding.

Risk of high-grade malignancy in parotid gland tumors as classified by the Milan System for Reporting Salivary Gland Cytopathology

BACKGROUND

The Milan System for Reporting Salivary Gland Cytopathology (Milan System) has previously shown its diagnostic utility by categorizing the seven cytology findings in salivary gland lesions. However, there has been lack of study about the risk of high-grade malignancy in the cytology diagnosis based on the Milan System. Thus, we tried to identify the diagnostic ability of the Milan System for high-grade malignancy and to suggest an improved diagnostic approach for preoperative estimation of high-grade malignancy using the Milan System.

METHODS

A total of 413 patients with parotid gland tumors, who had undergone surgical resection from 2011 to 2015 were included in the present study retrospectively. Cytopathology was reclassified according to the Milan System by two independent reviewers. The outcomes were risk of malignancy and risk of high-grade malignancy. The diagnostic performance of the Milan System category [Malignant] for detecting high-grade malignancy was calculated.

RESULTS

The risk of malignancy was 83.3% and 100% in the Milan System categories [Suspicious for Malignancy] and [Malignant], respectively. Meanwhile, the risk of high-grade malignancy was 16.7% and 55.9% in these two categories. Disease-free survival of patients with high-grade malignancy was significantly worse than those with low- and intermediate-grade malignancy. Union combining the Milan System category [Malignant] with the presence of nodal metastasis suggested high-grade malignancy with an acceptable diagnostic sensitivity (0.889-0.963) and negative predictive value (0.900-0.966).

CONCLUSIONS

The Milan System category [Malignant] with the presence of nodal metastasis suggested parotid gland tumors as high-grade malignancy in a pretreatment setting.

FAM129A regulates autophagy in thyroid carcinomas in an oncogene-dependent manner

We previously proposed that high expression of FAM129A can be used as a thyroid carcinoma biomarker in preoperative diagnostic exams of thyroid nodules. Here, we identify that FAM129A expression is increased under nutrient and growth factor depletion in a normal thyroid cell line (PCCL3), overlapping with increased expression of autophagy-related protein and inhibition of AKT/mTOR/p70S6K. Supplementation of insulin, TSH and serum to the medium was able to reduce the expression of both FAM129A and autophagy-related protein and reestablish the AKT/mTOR/p70S6K axis. To determine the direct role of FAM129A on autophagy, FAM129A was transfected into PCCL3 cells. Its overexpression induced autophagic vesicles formation, evidenced by transmission electron microscopy. Co-expression of FAM129A and mCherry-EGFP-LC3B in PCCL3 showed an increased yellow puncta formation, suggesting that FAM129Ainduces autophagy. To further confirm its role on autophagy, we knockdown FAM129A in two thyroid carcinoma cell lines (TPC1 and FTC-236). Unexpectedly, FAM129A silencing increased autophagic flux, suggesting that FAM129A inhibits autophagy in these models. We next co-transfected PCCL3 cells with FAM129A and RET/PTC1 and tested autophagy in this context. Co-expression of FAM129A and RET/PTC1 oncogene in PCCL3 cells, inhibited RET/PTC1-induced autophagy. Together, our data suggest that, in normal cells FAM129A induces autophagy in order to maintain cell homeostasis and provide substrates under starvation conditions. Instead, in cancer cells, decreased autophagy may help the cells to overcome cell death. FAM129A regulates autophagy in a cell- and/or context-dependent manner. Our data reinforce the concept that autophagy can be used as a strategy for cancer treatment.

Associations between Bethesda categories and tumor characteristics of conventional papillary thyroid carcinoma

PURPOSE

The aim of this study was to investigate the associations of Bethesda categories III, V, and VI with the clinical and pathological features of thyroid nodules surgically confirmed as conventional papillary thyroid carcinomas (PTCs).

METHODS

We analyzed 1,990 consecutive patients diagnosed with conventional PTC at surgery with preoperative Bethesda categories III, V, or VI. We determined the odds ratio (ORs) of the clinical and pathological variables associated with categories III and V, using category VI as the reference.

RESULTS

Category III and V PTCs had a smaller pathological tumor size (OR, 0.934 and OR, 0.969, respectively) and less frequently had central lymph node metastasis (OR, 0.487 and OR, 0.780, respectively) than category VI PTCs. Category III PTCs less frequently showed suspicious ultrasonographic features (OR, 0.296) than category VI PTCs, and category V PTCs less frequently had gross extrathyroidal extension, with borderline significance (OR, 0.643; P=0.059).

CONCLUSION

Conventional PTCs with a preoperative Bethesda category of III or V may less frequently exhibit poor prognostic factors than those with malignant cytology.

Patients with Indeterminate Thyroid Nodules at Cytology and Cancer at Histology Have a More Favorable Outcome Compared with Patients with Suspicious or Malignant Cytology

BACKGROUND

The outcomes of patients with thyroid cancer proven by histology in patients in whom cytology was Thy 3 (indeterminate; Thy 3 patients in this study) based on the Italian consensus classification compared with those in whom cytology was Thy 4 (suspicious for malignancy) or Thy 5 (indicative for malignancy) (Thy 4-5 patients here) remains unclear.

OBJECTIVE

To analyze the outcome of 371 Thy 3 patients versus 269 Thy 4-5 patients homogeneously treated with total thyroidectomy and ¹³¹I activity.

RESULTS

T1 stage was observed in 46.0% of Thy 3 and in 38.8% of Thy 4-5 patients (p = 0.02), N0 in 95.9% of Thy 3 and in 75.5% of Thy 4-5 patients (p < 0.0001). 35/261 (9.6%) Thy 3 and 85/269 (31.5%) Thy 4-5 patients required >30 mCi of ¹³¹I (p < 0.0001). 359/371 (96.8%) Thy 3 and 232/269 (86.2%) Thy 4-5 patients were free of disease at the end of follow-up (p < 0.001). The time required to obtain 50% of patients in remission was 2 years in Thy 3 and 4 years in Thy 4-5 patients (p < 0.001). The most common histological type was the follicular variant of papillary thyroid carcinoma (FV-PTC) in Thy 3 patients (239/371, 64.4%) and the classic variant in Thy 4-5 patients (185/269; 68.8%). The FV-PTC had better prognostic features compared with the other PTC variants: T1 stage was observed in 133/277 (48.0%) FV-PTC patients and in 146/363 (40.0%) patients with the other variants (p < 0.001), N0 was present in 265/277 (96.0%) FV-PTC and in 290/363 (79.8%) patients with the other variants (p < 0.001). Overall, 267/277 FV-PTC patients (96.4%) and 324/363 patients (89.0%) with the other variants were free of disease (p < 0.0008) at the end of follow-up, and the time required to obtain 50% of patients in remission was 2 years in FV-PTC and 4.0 years in the other variants (p < 0.001).

CONCLUSION

Patients with Thy 3 cytology have better outcomes of thyroid cancer compared with patients with Thy 4 or Thy 5 cytology, and indeterminate cytology is commonly associated with the less aggressive FV-PTC.

How to handle borderline/precursor thyroid tumors in management of patients with thyroid nodules

Thyroid carcinomas originating from follicular cells have the prognosis of heterogeneous diseases, but pathologists classify them all as malignant disease. Epidemiologists have issued a stern warning regarding over-diagnosis and overtreatment of patients with indolent thyroid tumors that cause no harm to the patients. Review of the literature revealed that there were several proposals of borderline/precursor tumors to some indolent thyroid carcinomas. Thyroid tumor of uncertain malignant potential (UMP) was first proposed by Williams for encapsulated follicular pattern thyroid tumors to solve problems due to observer variation. Rosai et al. proposed to rename papillary microcarcinoma (PMC) to papillary micro-tumor as the overwhelming majority of them are of no clinical significance. Liu et al. proposed well-differentiated tumor with uncertain behavior (WDT-UB) which covered WDT of UMP (WDT-UMP) and non-invasive encapsulated follicular variant of papillary thyroid carcinoma (EFVPTC). The EFVPTC without invasion was renamed as non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) by an international panel of pathologists. A new prognostic classification of thyroid tumors was proposed by Kakudo et al., in which extremely low risk tumors were grouped in a borderline tumors category. The borderline/precursor thyroid tumors included encapsulated tumors [capsular invasion only follicular carcinoma, encapsulated papillary carcinoma without invasion, WDT-UMP and follicular tumor of UMP (FT-UMP)] and non-encapsulated tumors (PMC). The UMP and NIFTP were incorporated in the 4th edition WHO classification of thyroid tumors as a new tumor entity in chapter 2-2A: other encapsulated follicular patterned thyroid tumors. Their behavior codes were decided to be 1 (borderline or uncertain behavior), and not 0 (benign), 2 (in situ carcinoma) or 3 (malignant). These borderline/precursor thyroid tumors are indolent tumors biologically and should be treated more conservatively than as previously recommended for thyroid follicular cell carcinomas [total thyroidectomy (TTX) followed by radio-active iodine (RAI) treatment] by western clinical guidelines.

Follicular thyroid cancer and Hürthle cell carcinoma: challenges in diagnosis, treatment, and clinical management

Follicular thyroid cancer is the second most common differentiated thyroid cancer histological type and has been overshadowed by its more common counterpart-papillary thyroid cancer-despite its unique biological behaviour and less favourable outcomes. In this Review, we comprehensively review the literature on follicular thyroid cancer to provide an evidence-based guide to the management of these tumours, to highlight the lack of evidence behind guideline recommendations, and to identify changes and challenges over the past decades in diagnosis, prognosis, and treatment. We highlight that correct identification of cancer in indeterminate cytological samples is challenging and ultrasonographic features can be misleading. Despite certain unique aspects of follicular thyroid cancer presentation and prognosis, no specific recommendations exist for follicular thyroid cancer and Hürthle cell carcinoma in evidence-based guidelines. Efforts should be made to stimulate additional research in this field.

Impact of oncogene panel results on surgical management of cytologically indeterminate thyroid nodules

BACKGROUND

The impact of oncogene panel results on the surgical management of indeterminate thyroid nodules (ITNs) is currently unknown.

METHODS

Surgical management of 649 patients consecutively evaluated from October 2008 to April 2016 with a single nodule biopsied and indeterminate cytology (193 evaluated with and 456 without oncogene panels) was assessed and compared. Histological features of 629 consecutively resected ITNs (164 evaluated with and 465 without oncogene panels) were also characterized and compared.

RESULTS

Oncogene panel evaluation was associated with higher rates of total thyroidectomy (45% vs 28%; P = .006), and central lymph node dissection (19% vs 12%; P = .03) without increasing the yield of malignancy or decreasing the rate of completion thyroidectomy. Most malignancies (64%), including 83% of those with driver mutation identified, were low-risk cancers for which a lobectomy could have been sufficient initial treatment.

CONCLUSION

Current oncogene panel results seem insufficient to guide the surgical extent of solitary ITNs.

High suspicion US pattern on the ATA guidelines, not cytologic diagnosis, may be a predicting marker of lymph node metastasis in patients with classical papillary thyroid carcinoma

BACKGROUND

To evaluate the utility of ultrasound (US) patterns based on the 2015 American Thyroid Association (ATA) guidelines and cytologic diagnosis of the Bethesda System for Reporting Thyroid Cytopathology as predicting markers for lymph node metastasis (LNM) in classical papillary thyroid carcinoma (PTC).

METHODS

A retrospective analysis of 657 patients with classical PTC who underwent ultrasound-guided fine-needle aspiration (US-FNA) and surgery were included in this study. The associations between LNM and the US features or the Bethesda System for Reporting Thyroid Cytopathology were evaluated.

RESULTS

Multivariate logistic regression analysis showed that the high suspicion US pattern was independently associated with LNM (odds ratio = 3.081; 95% confidence interval = 1.515-6.262; P = .002). And the Bethesda category was not significantly associated with LNM (P = .056).

CONCLUSIONS

The high suspicion US pattern of the 2015 ATA guidelines, not cytologic diagnosis, could be a predicting marker of LNM in patients with classical PTC.

Shear Wave Elastography in Thyroid Nodules with Indeterminate Cytology: Results of a Prospective Bicentric Study

BACKGROUND

The clinical management of thyroid nodules with indeterminate cytology (IC) remains challenging. The role of shear wave elastography (SWE) in this setting is controversial. The aim of the study was to assess the performances of SWE in terms of prediction of malignancy, reproducibility, and combined analysis with ultrasound (US) examination in thyroid nodules with IC.

METHODS

This prospective study was conducted in two referral centers. Eligible patients had a thyroid nodule ≥15 mm with IC (Bethesda class III-V) for which surgery had been recommended. Patients underwent a standardized US evaluation combined with a SWE exam followed by surgery. SWE parameters included mean (meanEI; kPa) and max (maxEI) elasticity values, and ratio (meanEI nodule/parenchyma).

RESULTS

One hundred and thirty-one nodules (median size 30 mm) in 131 patients were studied. IC was class III in 28%, class IV in 64%, and class V in 8% of cases. After surgery, 21 (16%) nodules were malignant, including nine papillary thyroid cancers (PTC), six follicular thyroid cancers, five poorly differentiated carcinomas, and one large B-cell lymphoma. SWE parameters were similar in benign and malignant nodules, including meanEI (20.2 vs. 19.6 kPa), maxEI (34.3 vs. 32.5 kPa), and ratio (1.57 vs. 1.38). In malignant nodules, meanEI, maxEI, and ratio were higher in the classic PTC variants (n = 4) than in the other PTC variants (n = 5; p < 0.02) and in non-PTC tumors (n = 12; p < 0.005). Intra- and inter-observer coefficients of variations for meanEI in nodules were 23% and 26%, respectively. The French Thyroid Imaging Reporting and Data System score, the American Thyroid Association US classification, and the EU-Thyroid Imaging Reporting and Data System were not associated with malignancy.

CONCLUSIONS

Despite high elasticity values in classic PTC variants, conventional SWE indexes failed to discriminate between benign and malignant tumors in thyroid nodules with IC.