The Bethesda System For Reporting Thyroid Cytopathology Research Articles

Diagnostic Accuracy of Bethesda Classification of Thyroid Nodules at a Kenyan Hospital: A Retrospective Study

Background: The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) was developed to standardize the reporting of thyroid nodule fine-needle aspiration cytology (FNAC) results. The adoption of TBSRTC is based on the implied risk of malignancy per category, but this has shown wide variation in different regions worldwide. Aim: The aim of this study is to determine the diagnostic accuracy of the Bethesda classification of thyroid nodules in a Kenyan hospital. Methods: A retrospective longitudinal study examined FNAC and histopathology data of thyroid gland nodules at a Kenyan hospital from 2010 to 2019; specimens from 347 patients were found. An analysis was performed to determine the diagnostic accuracy of the Bethesda classification in detecting malignancy among these patients. Results: The malignancy rate was 16.1%. The risk of malignancy as per the Bethesda category was as follows: non-diagnostic— 19.6%, benign—6%, atypia of undetermined significance—20%, follicular neoplasm—16.7%, suspicious for malignancy—80%, and malignant—85.7%. The diagnostic properties of FNAC defining “malignant” and “suspicious for malignancy” categories as malignant were as follows: sensitivity—64.7%, specificity—97.6%, and accuracy—92.7%. Conclusion: The Bethesda classification had high diagnostic accuracy, with the risk of malignancy consistent with the Bethesda findings. Classifying malignancy as “malignant” and “suspicious for malignancy” yielded the most favorable diagnostic properties for FNAC.

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

ABSTRACT 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.

Prevalence of malignancy in thyroid nodules with AUS cytopathology: A retrospective cross-sectional study.

Category III (AUS; Atypia of Undetermined Significance) of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) was established to describe thyroid nodule features that are neither benign nor cancerous. This study aims to evaluate the rate of thyroid malignancy in patients diagnosed with AUS at the Armed Forces Hospital Southern Region (AFHSR), Saudi Arabia. The patients (508) diagnosed with AUS in their thyroid nodules underwent fine-needle aspiration cytology (FNAC). Data were collected through a chart-based approach, reviewing patients' medical records and relevant information. Among the cases, the majority were females (84.6%). Among the different age groups, individuals between 40 and 50 years had the highest prevalence of thyroid nodules (32.5%). Approximately 27% of patients exhibited tumor sizes larger than 4 cm. FNAC results revealed 16.5% benign, 26% AUS, and 22.4% follicular neoplasm cases. Histopathology indicated 54.1% of benign and 37.2% of malignant cases. Papillary carcinoma accounts for 80.4% of all malignant cases. A significant correlation was observed between FNAC and postoperative histopathology (P value < 0.05). Hypoechoic nodules exhibited 33.9% of malignant cases, and calcification was observed in 25% of the cases. A significant association was found between malignancy and echogenicity and between malignancy and calcification (P value = 0.003 and 0.001, respectively). The findings of this study identify malignancy in thyroid nodules with AUS cytopathology, particularly in the Southern region of Saudi Arabia. The correlation between pre-surgery FNAC and postoperative histopathology supports FNAC's diagnostic value. Additionally, echogenicity and calcification can potentially contribute to predicting nodule malignancy.

The Bethesda System for Reporting Thyroid Cytopathology in theAfrican American population: A tertiary centre experience.

The reported risk of malignancies (ROM) remains controversial for fine needle aspiration (FNA) of thyroid nodules in the African American (AA) population. Herein, the ROM along with frequency was assessed for each of the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) diagnostic categories. The electronic pathology archive of a large academic hospital was retrospectively searched for cytopathology reports of thyroid nodules in AA patients (2010-2019) and Non-African American (NAA) control cases. The patients' demographic, thyroid nodule characteristics, FNA results using TBSRTC and surgical diagnoses were recorded, whenever available. Three hundred ninety-one cases were identified, 317 females (81.1%) and 74 males (18.9%) with median age 50.0 (SD = 14.4). The mean size of the nodules was 2.1 cm (SD = 1.4). The Bethesda categories were: 5.4% (I), 35.0% (II), 35.3% (III), 7.7% (IV), 3.3% (V) and 13.3% (VI). The overall ROM of thyroid nodules was 43.8% (89/203) on surgical follow-up (203/391). The ROM in each Bethesda categories were: 33.3% (I), 11.6% (II), 35.2% (III), 15.8% (IV), 83.3% (V) and 100% (VI) on surgical follow-up. The frequency of thyroid nodules was higher in AA females; however, the ROM was higher in AA males (48.3%) compared with AA females (41.2%). The ROM in Categories I, II and III was higher than those reported in the TBSRTC while being similar in Categories IV, V and VI. The overall risk of thyroid malignancy in our AA patient population was higher than those in the literature. The overall ROM of thyroid nodules in AA males was higher than of AA females.

Individual Ultrasonographic Characteristics of Thyroid Nodules and Their Cytopathological Correlation to Determine Malignancy Risk.

Background Ultrasonographic evaluation of thyroid nodules is challenging due to their high frequency and low malignancy rate. The risk stratification system developed by the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) focuses on addressing the primary contemporary objectives for these lesions, aiming to decrease unnecessary biopsies while maintaining a similar specificity compared with other risk stratification systems. Generally, when indicative of malignancy by ultrasound findings, the next best step in management is an evaluation by fine needle aspiration biopsy (FNAB) and cytological analysis with The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) resultsthat determine further evaluation requirements, actions that are based on the risk of malignancy (ROM) of the assigned category, which could include surgical intervention. Objectives To validate and analyze the individual impact of each ultrasonographic finding indicative of malignancy in the ACR TI-RADS guidelines based on their respective correlation with results obtained by TBSRTC. Materials and method Reports for 212 thyroid ultrasound-guided FNABs from 2018 to 2020 were assessed. Only 117 had both ACR TI-RADS and TBSRTC reports available and were analyzed. Nodules were divided into two groups: ROM < 5% (Bethesda 1, 2; n = 58), and ROM > 5% (Bethesda 3, 4, 5, 6; n = 59).Statistical analysis was performed using the x2 test and bivariate logistic regression model for each characteristic included in ACR TI-RADS. Results Individual ultrasound characteristics with a more pronounced distribution towards the Bethesda > 5% malignancy group were: solid or almost completely solid composition (n=53, 62.3%), very hypoechoic echogenicity (n=3, 75%), wider-than-tall shape (n=50, 50.5%), lobulated or irregular margin (n=23, 65.7%), punctate echogenic foci (n=18, 72%), and thyroid isthmus location (n=6, 75%). Statistically significant individual ultrasonographic characteristics indicative of malignancy included solid or almost completely solid (p = 0.005), very hypoechoic echogenicity (p = 0.046), margin lobulated or irregular (p = 0.031), and punctate echogenic foci (p = 0.015). No significant association was found in the taller-than-wide shape for differentiating malignant from benign lesions (p = 0.969). Conclusions Specific ultrasound characteristics identified in the ACR TI-RADS system demonstrate a stronger correlation with an increased risk of malignancy when compared with cytologic evaluation results. These characteristics include a solid composition, lobulated or irregular margins, punctate echogenic foci, and very hypoechoic echogenicity. Our findings revealedthat the scale points for the taller-than-wide characteristic do not adequately represent its true influence on the risk of malignancy.

Correlation Between the Thyroid Imaging Reporting and Data System and Bethesda System of Cytology in Thyroid Nodule Evaluation

Background: Accurate diagnosis of thyroid nodules is important for avoiding unnecessary surgeries and allowing timely treatment. Ultrasound and fine needle aspiration cytology (FNAC) are the most commonly used diagnostic procedures. Objective: To correlate ultrasonography with the FNAC report findings using the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) and the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) in differentiating malignant from benign thyroid nodules. Patients and Methods: A prospective study conducted from January 2021 to January 2024 assessed 103 cases of thyroid nodules who underwent ultrasound examination and fine needle aspiration. Ultrasonography findings were analyzed and correlated with FNA cytology reports based on ACR-TIRADS and BSRTC. Results: Patients were predominantly female, n = 87 (84.4%). Most of the patients were in the 31–40 year group (n = 55, 53.39%). Most of the patient nodules had TIRADS 3 (n = 59, 57.28%), followed by TIRADS 2 (n = 20, 18.44%). When comparing the ACR TI-RADS scoring system with the TBSRTC, the percentage of malignancy for TR1, 2, 3, 4, and 5 was 0, 0, 1.6, 80, and 89%, respectively. In our study, the overall sensitivity and specificity of the TIRADS score were 94.11% and 96.51%, respectively. PPV: 84.21%; NPV: 98.80%; and accuracy: 96.11%. In addition, there was a significant association between TIRADS and the Bethesda system of classification (P &lt; 0.001). Conclusion: ACR-TIRADS scoring is highly sensitive and accurate for diagnosing thyroid malignant nodules. It is a sensitive tool and could be used alone to determine the nature of thyroid nodules. Keywords: Thyroid malignancies, Ultrasonography, Yemen

Correlation Between the Thyroid Imaging Reporting and Data System and Bethesda System of Cytology in Thyroid Nodule Evaluation

Background: Accurate diagnosis of thyroid nodules is important for avoiding unnecessary surgeries and allowing timely treatment. Ultrasound and fine needle aspiration cytology (FNAC) are the most commonly used diagnostic procedures. Objective: To correlate ultrasonography with the FNAC report findings using the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) and the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) in differentiating malignant from benign thyroid nodules. Patients and Methods: A prospective study conducted from January 2021 to January 2024 assessed 103 cases of thyroid nodules who underwent ultrasound examination and fine needle aspiration. Ultrasonography findings were analyzed and correlated with FNA cytology reports based on ACR-TIRADS and BSRTC. Results: Patients were predominantly female, n = 87 (84.4%). Most of the patients were in the 31–40 year group (n = 55, 53.39%). Most of the patient nodules had TIRADS 3 (n = 59, 57.28%), followed by TIRADS 2 (n = 20, 18.44%). When comparing the ACR TI-RADS scoring system with the TBSRTC, the percentage of malignancy for TR1, 2, 3, 4, and 5 was 0, 0, 1.6, 80, and 89%, respectively. In our study, the overall sensitivity and specificity of the TIRADS score were 94.11% and 96.51%, respectively. PPV: 84.21%; NPV: 98.80%; and accuracy: 96.11%. In addition, there was a significant association between TIRADS and the Bethesda system of classification (P &lt; 0.001). Conclusion: ACR-TIRADS scoring is highly sensitive and accurate for diagnosing thyroid malignant nodules. It is a sensitive tool and could be used alone to determine the nature of thyroid nodules.

Highlights of the 2023 Bethesda System for Reporting Thyroid Cytopathology, 3rd Edition

The Bethesda System for Reporting Thyroid Cytopathology (TBSRCT) is crucial for cytopathologists to use a standardized, category-based reporting system for thyroid fine needle aspirations and is effective for clear communication with the referring physicians. The new Bethesda System for Reporting Thyroid Cytopathology, the third edition in 2023, provides several key updates. The most important update is the assignment of only single name for each of the six diagnostic categories: (I) nondiagnostic; (II) benign; (III) atypia of undetermined significance; (IV) follicular neoplasm; (V) suspicious for malignancy; and (VI) malignant. An implied risk of malignancy (ROM) for each of six categories has been updated based on extensively published data since the second edition of TBSRTC in 2017 and offers both an average ROM for each category and the expected range of cancer risk. Estimated final ROM after excluding “Noninvasive Follicular Thyroid Neoplasm with Papillary Like Nuclear Features (NIFTP)” for each of six categories has been updated based on the reported mean decreases in the ROM if excluding NIFTP. For atypia of undetermined significance (AUS) category, the subcategorization is simplified and more formalized into 2 subgroups, AUS-nuclear atypia or AUS-other, based on the implied ROM and molecular profiling. For the pediatric thyroid disease, pediatric ROMs and management algorithms are newly added for the same six reporting categories for this age group. New or revised disease nomenclatures including high-grade follicular-derived carcinoma has been updated according to the recently published 2022 World Health Organization Classification of Thyroid Neoplasms. Brand new two chapters are added including clinical perspectives and imaging studies (Chap. 13) and the use of molecular and other ancillary tests (Chap. 14). The atlas is updated with new images to illustrate more effectively for new disease entity and diagnostic criteria.

The Incidence of Thyroid Cancer in Bethesda III Thyroid Nodules: A Retrospective Analysis at a Single Endocrine Surgery Center.

Fine-needle aspiration cytology (FNAC) is widely used to diagnose and monitor thyroid nodules. The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) is the standard for interpreting FNAC specimens. The risk of malignancy in Bethesda III nodules, also known as Atypia of Undetermined Significance (AUS), varies significantly throughout several studies published worldwide. This retrospective study examines the risk of cancer in thyroid FNAC categorized as Bethesda III as identified in the final histopathology of thyroidectomy specimens at a single endocrine surgery center. This retrospective cohort analysis included 1038 consecutive patients who underwent elective thyroid surgery with complete follow-up data between January 2020 and March 2024. Preoperative data on clinical and pathological characteristics have been collected. The final histopathology report from the thyroidectomy specimen was compared to the results of the preoperative FNAC on nodules that were judged to be Bethesda category III. Statistical methods were performed using SPSS version 29. A total of 670 ultrasound-guided FNACs (64.5%) performed during the study period were included in the final analysis. The study population was predominantly female, represented by 79.6% of patients with a mean age of 42.5 (SD 12.1), while 20.4% were male and significantly older with mean age of 45.13 years (p = 0.02). The FNAC inadequacy rate was 5.1%, which was associated with a high risk of malignancy (6 out of 34; 17.6%). Out of the total sample size of 170 patients classified as group III, 57 were found to have malignancies in final surgical histopathology, representing 33.5% of the cases within this category. The secondary gender-related outcome analysis showed that female patients classified under the Bethesda II category had a significantly higher risk of malignancy, with a rate of 21.2%, compared to males who had a malignancy rate of 3.4% in the same Bethesda category (p = 0.001, chi-square test). However, the female patients exhibited prognostically superior non-invasive tumors compared to male individuals (p = 0.02, chi-square test). This study's results indicate that Bethesda categories II and III are associated with a higher risk of malignancy in comparison to the reports of the first and third editions of the TBSRTC, particularly for female patients classified under category II.

Diagnostic interobserver agreement for thyroid fine-needle aspirates: Effects of reviewer experience and molecular diagnostics.

Few cytologically indeterminate thyroid fine-needle aspirations (FNAs) harbor BRAF V600E. Here, we assess interobserver agreement for The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) category III (atypia of undetermined significance [AUS]) FNAs harboring BRAF V600E and contrast their features with those harboring non-BRAF V600E alterations, with attention to cytopathology experience. Seven reviewers evaluated 5 AUS thyroid FNAs harboring BRAF V600E. To blind reviewers, cases were intermixed with 19 FNAs falling within other TBSRTC categories and in which genetic alterations other than BRAF V600E had been identified (24 FNAs total). Interobserver agreement against both "index" and most popular ("mode") diagnoses was calculated. Four additional BRAF V600E cases were independently reviewed. Reviewers included 3 trainees and 3 American Board of Pathology (board)-certified cytopathologists. Board-certified cytopathologists, whose experience ranged from 2 to more than 15 subspecialty practice years, had known AUS rates. BRAF V600E was identified in 5 of 260 (2%) AUS FNAs. Interobserver agreement was higher among cytopathologists with more experience. Mode diagnosis differed from index diagnosis in 6 of 11 cases harboring RAS-like alterations; mode diagnosis was AUS in 4 of 5 BRAF V600E FNAs. Atypia of undetermined significance of thyroid FNAs harboring BRAF V600E is uncommon yet relatively reproducible, particularly among pathologists with experience. It is advisable to sequence BRAF across V600 in such cases.

Atypia of undetermined significance and ThyroSeq v3-positive call rates as quality control metrics for cytology laboratory performance.

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) recommends an upper limit of 10% for atypia of undetermined significance (AUS). Recent data suggest that this category might be overused when the rate of cases with molecular positive results is low. As a quality metric, the AUS and positive call rates for this facility's cytology laboratory and each cytopathologist (CP) were calculated. A retrospective analysis of all thyroid cytology cases in a 4.5-year period was performed. Cases were stratified by TBSRTC, and molecular testing results were collected for indeterminate categories. The AUS rate was calculated for each CP and the laboratory. The molecular positive call rate (PCR) was calculated with and without the addition of currently negative to the positive results obtained from the ThyroSeq report. A total of 7535 cases were classified as nondiagnostic, 7.6%; benign, 69%; AUS, 17.5%; follicular neoplasm/suspicious for follicular neoplasm, 1.4%; suspicious for malignancy, 0.7%; and malignant, 3.8%. The AUS rate for each CP ranged from 9.9% to 36.8%. The overall PCR was 24% (range, 13%-35.6% per CP). When including cases with currently negative results, the PCR increased to 35.5% for the cytology laboratory (range, 13%-42.6% per CP). Comparison analysis indicates a combination of overcalling benign cases and, less frequently, undercalling of higher TBSRTC category cases. The AUS rate in the context of PCR is a useful metric to assess cytology laboratory and cytopathologists' performance. Continuous feedback on this metric could help improve the overall quality of reporting thyroid cytology.

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 criteriaoutlined 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.

A Comprehensive Approach to the Thyroid Bethesda Category III (AUS) in the Transition Zone Between 2nd Edition and 3rd Edition of The Bethesda System for Reporting Thyroid Cytopathology: Subcategorization, Nuclear Scoring, and More

Significant interobserver variabilities exist for Bethesda category III: atypia of undetermined significance (AUS) of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC). Thus, subcategorization of AUS including AUS “nuclear” and AUS “other” is proposed in the recent 3rd edition of TBSRTC. This study investigated the impact of the nuclear features/architectural features/nuclear score (NS) (3-tiered)/subcategories and subgroups on risk of malignancy (ROM) in thyroid fine-needle aspirations (FNA). 6940 FNAs were evaluated. 1224 (17.6%) cases diagnosed as AUS were reviewed, and 240 patients (initial FNAs of 260 nodules and 240 thyroidectomies) were included. Subcategories and subgroups were defined according to TBSRTC 2nd and 3rd editions. Histological diagnostic groups included nonneoplastic disease, benign neoplasm, low-risk neoplasm, and malignant neoplasm. Overall, ROM was 30.7%. ROM was significantly higher in FNAs with nuclear overlapping (35.5%), nuclear molding (56.9%), irregular contours (42.1%), nuclear grooves (74.1%), chromatin clearing (49.4%), and chromatin margination (57.7%), and these features were independent significant predictors for malignancy. FNAs with NS3 had significantly higher ROM (64.2%). Three-dimensional groups were significantly more frequent in malignant neoplasms (35.7%). ROM was significantly higher in AUS-nuclear subcategory (48.2%) and in AUS-nuclear and architectural subcategory (38.3%). The highest ROM was detected in AUS-nuclear1 subgroup (65.2%). ROM was significantly higher in the group including AUS-nuclear and AUS-nuclear and architectural subcategories, namely “high-risk group” than the group including other subcategories, namely “low-risk group” (42.0%vs 13.9%). In conclusion, subcategorization may not be the end point, and nuclear scoring and evaluation of architectural patterns according to strict criteria may provide data for remodeling of TBSRTC categories.

Differentiated high grade thyroid carcinomas: Diagnostic consideration and clinical features

BackgroundDifferentiated high-grade thyroid carcinomas (DHGTCs) are a new diagnostic entity most recently defined in the 2022 World Health Organization's (WHO) Classification of Endocrine and Neuroendocrine Tumors. This new entity has been minimally described in the literature, and additional cases classified as such are missing. Materials and methodsCases of DHGTCs diagnosed at our institution from 2012 to 2022 were identified, and the following were reviewed: cytologic and histologic diagnoses, ancillary testing, immunohistochemical staining, treatments, and patient outcomes. Immunohistochemical staining for Ki67 was performed on selected cases lacking this immunostain. A systematic literature review of the English literature on DHGTCs from 2013 to 2023 was performed using PubMed and Embase. ResultsCase cohort included 32 cases of DHGTCs, with an average age of 52.6 years (range 17–84 years) and a male:female ratio of 1.3:1. All cases underwent fine needle aspiration (FNA) and were categorized by The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) as follows: 14 cases as malignant (43.8 %), 10 as follicular neoplasm (31.3 %), 5 as atypia of undetermined significance (15.6 %), 2 as suspicious for malignancy (6.2 %), and 1 as non-diagnostic (3.1 %). The average tumor size was 5.15 cm, and most were papillary thyroid carcinoma (28, 87.5 %), with classic subtype being the most common. Twenty-one cases revealed tumor necrosis and the mitotic activity in lesions without necrosis averaged to 5.5 mitoses per 2 mm2 (range 0–7). The average Ki67 proliferative index was 5.6 %. Extrathyroidal extension was seen in 17, angioinvasion in 21, lymphatic invasion in 7, and perineural invasion in 1 case. Foci of solid or trabecular growth were identified in five cases. Lymph node metastases at the time of diagnosis were noted in 10 cases and 7 demonstrated distant metastases or locoregional recurrence. To date, 25 patients are alive, and one has died from disease. ConclusionsOur institutional experience demonstrates that DHGTC is a rare, but aggressive thyroid tumor subtype that requires consideration in the setting of a well-differentiated thyroid neoplasm to appropriately assess for possible disease recurrence and determination of patient prognosis.

Thyroid nodules and the risk of cancer based on fine-needle aspiration using Bethesda classification in Riyadh, Saudi Arabia

Background: The presence of thyroid nodules is common and can only be diagnosed through radiographic examination. Fine needle aspiration is an essential technique to identify the type of nodules and their malignancy categorization. This study aims to evaluate the effectiveness of the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) method in the Security Force Hospital, Riyadh, Saudi Arabia, and to estimate the frequency of Bethesda categorization in reporting fine needle aspiration sampling and predicting the malignancy risk in Riyadh. Methods: This is a retrospective chart review that included records of patients with sonographic thyroid nodules and an indicator for fine needle aspiration based on the American Thyroid Association guideline recommendations. The results of FNA were then classified based on the Bethesda system. Data analysis was executed through the Statistical Package for the Social Sciences (SPSS) version 26. Results: This study included 519 patients over three years. The average age was 49.71±12.4. 74.4% were asymptomatic, 50.7% had a thyroid nodule, while 33.9% had a multinodular goiter. 30.6% of the nodules had a size between 1 to 1.49 cm. 42% had smooth borders. The nodules most commonly had a low suspicion of malignancy by sonography, and 22.7% of the patients underwent thyroid surgery; of them, 54.2% had malignancy. Higher Bethesda classes and a sonographic pattern of intermediate suspicion were common predictors associated with a significantly higher risk of malignancy (p-value &amp;lt; 0.001). Conclusion: Thyroid malignancy is commonly detected by thyroid surgery; the use of Bethesda classification is a predictor of thyroid malignancy, and its application in Saudi hospitals should be improved.

UTILITY OF THE 2023 BETHESDA SYSTEM AUS SUBCATEGORIZATION ON THYROID ASPIRATES.

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) is widely used for the standardized reporting of thyroid fine-needle aspiration (FNA) cytology. The 2023 revision of TBSRTC introduced specific subcategories for the classification of atypia of undetermined significance (AUS). This study tests the association between AUS subtypes and malignant diagnoses, namely AUS-nuclear atypia and AUS-other, in archived thyroid - FNA specimens with atypia from 2018-2022 at King Abdulaziz University Hospital. A total of 104 thyroid - FNA specimens with AUS were re-evaluated cytologically and correlated with subsequent surgical outcomes, along with a discussion of discrepant cases.

Chapter 11: Pediatric Differentiated Thyroid Cancers

ABSTRACT The document discusses pediatric differentiated thyroid cancer (DTC), focusing on papillary thyroid carcinoma (PTC), which is increasingly prevalent globally, including in India. Despite a more aggressive initial presentation in children, the long-term prognosis is generally positive. Key differences between pediatric and adult DTC are highlighted, such as a higher risk of malignancy in children with thyroid nodules and common RET/PTC gene rearrangements. There is a debate on the age cutoff for defining pediatric DTC, but the document suggests that 18 years is considered appropriate in the Indian context. Diagnostic methods, including ultrasonography-guided fine needle aspirate (FNA) and the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC), are emphasized. The importance of genomic analysis for indeterminate cytology is also proposed. Treatment approaches involve total thyroidectomy due to higher multifocality in children, with consideration of potential complications. Post-operative risk stratification, utilizing the TNM staging system, is seen as crucial and correlates with disease-free survival. Post-operative staging includes TSH-stimulated thyroglobulin (Tg) and anti-thyroglobulin antibody (ATg) levels, along with a diagnostic whole-body 131I scan to assess surgical completeness. Radioactive iodine therapy (RAI) is recommended for iodine-avid persistent/metastatic disease, with an empirical activity of 30 mCi for remnant ablation and adjustments based on age or weight. Regular follow-ups include monitoring TSH-suppressed Tg, Anti-Tg levels, and neck ultrasound. Dynamic risk stratification at 2 years refines risk based on treatment responses. Genetic considerations reveal prevalent RET fusion oncogene and less common BRAF mutations, which are associated with RAI refractoriness. In summary, the document provides a comprehensive understanding of pediatric DTC, emphasizing the need for tailored guidelines in the Indian context. It covers various aspects of diagnosis, surgery, and post-operative care, with a focus on age-appropriate management and ongoing research in this specialized field.

Comparison of diagnostic accuracy of conventional method and Bethesda system for reporting thyroid cytopathology in the diagnosis of various lesions of the thyroid: Experience from a tertiary care center of northeastern India

Background: Fine-Needle Aspiration Cytology (FNAC) is a valuable, minimally invasive diagnostic tool for discerning benign and malignant thyroid lesions. In the realm of thyroid cytopathology, both the traditional approach and the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) are widely utilized for diagnosing and categorizing these lesions. Aims and Objectives: This study aims to classify thyroid cytology smears using both the conventional method and the Bethesda system and to compare their findings with histopathological diagnoses. Method and Materials: A hospital-based cross-sectional study was conducted over one year, spanning from February 1, 2022, to January 31, 2023. We included 191 cases of FNAC thyroid lesions and categorized them following the guidelines of both the conventional system and the Bethesda system for reporting thyroid cytopathology. Sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy for both systems were calculated, with histopathology serving as the gold standard for comparison. Furthermore, we calculated the Risk of Malignancy (ROM) for each category within the Bethesda system. Results: The Bethesda system exhibited a notably high sensitivity of 83.33%, surpassing the conventional method's sensitivity of 50%, while both systems shared the same specificity of 90%. The diagnostic accuracy of the Bethesda system, at 89.13%, outperformed that of the conventional method, which stood at 84.78%. Conclusion: This study demonstrates a strong positive correlation with histopathology, indicating high sensitivity, specificity, and accuracy when employing TBSRTC, in contrast to the conventional method.

Non-papillary thyroid carcinoma diagnoses in The Bethesda System for Reporting Thyroid Cytopathology categories V and VI: An institutional experience

BackgroundThe non-papillary thyroid carcinoma (PTC) subgroups of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) categories V (Suspicious for malignancy) and VI (Malignant) are rare, and specific tumor typing is difficult. We aimed to analyze histologic outcomes and to investigate the points of caution. MethodsWe reviewed the electronic database and identified 12,215 cases of thyroid fine-needle aspiration cytology between 2013 and 2022. In total, 2783 patients were diagnosed with TBSRTC V or VI. Of these, 51 patients with non-PTC diagnosis were identified. Histological outcomes were analyzed with the cytologic findings. ResultsThe subgroups of non-PTC diagnoses in TBSRTC category V or VI consisted of medullary thyroid carcinoma (MTC) (13/51, 25.5 %), anaplastic thyroid carcinoma (3/51, 5.9 %), lymphoma (2/51, 3.9 %), metastatic tumor (4/51, 7.8 %), and malignant, not otherwise specified (NOS) (29/51, 56.9 %). The concordance rate of the histological outcomes was 30 % (12/40), predominantly comprising MTC cases. The obscuring factors for specific tumor typing in the suspicious for malignancy/malignant NOS cytology diagnosis group was mixed pattern of well differentiated thyroid carcinoma and less differentiated carcinoma cells (9/24, 37.5 %), low cellularity (7/24, 29.2 %) and a history of non-thyroid organ malignancy (6/24, 25 %). The less differentiated carcinoma component in mixed pattern consisted of 2 poorly differentiated thyroid carcinomas, 2 anaplastic thyroid carcinomas, 4 high-grade PTCs and 1 high-grade MTC. ConclusionThe high-grade feature of PTC or MTC cytology is a noteworthy obscuring factor in specific tumor typing of non-PTC cytology diagnosis.

Stratifying Indeterminate Cytology Thyroid Nodules by Combining Thyroid Imaging Reporting and Data Systems (TI-RADS) and The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC)

Objective: To determine the risk of malignancy of Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) indeterminate Thyroid Nodules (Bethesda III, IV and V) by combining cytologic (TSBRTC) and Thyroid Imaging Reporting and Data Systems (TI-RADS) ultrasonographic features based on final histopathology. Methods:Design: Retrospective review of recordsSetting: Tertiary Private Training HospitalParticipants: 551 recordsResults: Among 81 eligible participants, 59 out of 84 nodules (70.24%) wer malignant on histopathology. The malignancy risk of Bethesda classification was 60.87% (28 out of 46) for Bethesda III, 57.14% (8 out of 14) for Bethesda IV and 95.83% for Bethesda V. The malignancy risk for TI-RADS categories was 0 % (0/1) for TI-RADS 2, 50% (10 out of 20) for TI-RADS 3, 71.05 % for TI-RADS 4 and 91.67 % for TI-RADS 5. The highest risk of malignancy (100%) was associated with [Bethesda IV/TI-RADS 1, 2, and 3], [Bethesda V/TI-RADS 1, 2 and 3 [Bethesda IV and V/TI-RADS 1, 2 and 3] and [Bethesda IV/TI-RADS 5]. The lowest risk of malignancy (33.33%) was associated with [Bethesda III/TI-RADS1, 2 and 3]. A high Bethesda classification (Bethesda V) was almost 5x more likely to have a malignant anatomorphology compared with Bethesda III (p = .05) while a TI-RADS 4 or 5 category was almost 5x more likely to have a malignant anatomorphology compared to TI-RADS 1, 2 or 3 (p = .026). Conclusion: This study showed that TI-RADS scoring is a sensitive diagnostic classification in recognizing patients with thyroid cancer and combining Bethesda classification and TI-RADS scoring increases the sensitivity in the diagnosis of malignant thyroid nodules. A higher likelihood of malignancy is associated with higher Bethesda classification and TI-RADS scoring.