The Bethesda System For Reporting Thyroid Cytology Research Articles

Performance of thyroid fine needle aspiration biopsy in a low- and middle-income country.

Introduction The 6 categories of the Bethesda System for Reporting Thyroid Cytology (TBSRTC) with associated risk of malignancy (ROM) provide evidence-based clinical management guidelines. This study aimed to determine the ROM and accuracy of FNAB in South Africa (SA). Methods Thyroid specimens from 3 pathology laboratories registered between January 2015 and December 2019 were considered for inclusion. ROM was obtained per TBSRTC category by cytohistological correlation and dividing the total number of specimens with malignant histology by the total number of cases operated. Accuracy was calculated based on the Bethesda category and eventual malignant histology. Results Seventeen thousand seven hundred and seventy-three histology and 4 791 cytology cases were identified. Of the 4 791 cytology cases, 931 (19%) underwent surgery. More than a third (333, 35.8%) of cases were confirmed as malignant following histological assessment, with the majority being benign (584, 62.7%). The ROM for the non-diagnostic and benign categories was 24.3% and 20.5%. The highest ROM was for category VI (91.5%), followed by categories V (69.5%), IV (51.9%) and III (38.8%). Thyroid FNAB had a sensitivity of 73%, specificity of 74%, and overall accuracy of 74%. Conclusion Bethesda categories II and IV have a relatively higher ROM in SA compared to findings from other developed countries. The diagnostic accuracy of thyroid FNAB in SA and the high rate of non-diagnostic diagnoses (38%) require further investigation. A national thyroid registry could provide location-specific data to aid the implementation of appropriate local policies and national guidelines for practicing thyroid surgeons.

Evaluation of FNAC Thyroid Smears Using Bethesda System For Reporting Thyroid Cytopathology Nomenclature With Clinicopathological Correlation

Background: The study aimed to interpret thyroid cytology by the Bethesda System for reporting thyroid cytology (TBSRTC) and to analyze the distribution of lesions under various diagnostic categories and subcategories.
 Methodology: This study was conducted as an observational study at tertiary care centre on patients with thyroid lesions. After history taking and detailed local, general and systemic examination, thyroid function tests were conducted. Apart from this, ultrasonography of lesion was done. Patients were subjected to FNAC and after fixation smears were stained with Papanicolaou stain.
 Results: About 53% thyroid lesions were hemorrhagic, followed by 17% blood mixed colloid and 4% colorless serous fluid. Sample adequacy was noted in 93.5% cases in our study. According to Bethesda system of classification, majority of lesions were benign (81.5%) whereas 6.5% lesions were unsatisfactory. Only 6% lesions were categorsied as malignant.
 Conclusion: FNAC is widely accepted as the most accurate, sensitive, specific, and cost- effective diagnostic procedure in the preoperative assessment of thyroid nodules. It is the first line of investigation and can differentiate benign nodules from malignant nodules of the thyroid in 95% cases. Applying a standard reporting system for thyroid cytology may enhance the communication between pathologists and clinicians, assists them to find out the rate of malignancy in each cytological group, and facilitating a more reliable approach for patient management.

Diagnostic Reliability of the American College of Radiology Thyroid Imaging Reporting and Data System in Royal Commission Hospital, Kingdom of Saudi Arabia

BACKGROUND: The American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) classified and predicted the risk of thyroid nodule malignancy with ultrasound scan scoring system. AIM: Hence, we aimed to investigate the value of the combined use of ultrasound ACR TI-RADS scoring and ultrasound-guided thyroid fine needle aspiration cytology (FNAC) based on the Bethesda System for Reporting Thyroid Cytology (TBSRTC) for assessing the accuracy tests of diagnosing low and high-risk thyroid nodules of ACR TI-RADS. METHODS: We enrolled 392 patients with thyroid nodules who underwent ultrasound scanning and scoring using the ACR TI-RADS classification along with ultrasound-guided thyroid FNAC and scoring with TBSRTC. The two methods were grouped as low and high risk of malignancy to evaluate the accuracy of ACR TI-RADS. RESULTS: Three hundred and ninety-two patients were enrolled in the study. The mean (Standard deviation [SD]) age was 46.03 (13.96) years, 332 (84.7%) were females and the mean (SD) of body mass index was 31.90 (22.32) kg/m2 and Vitamin D 17.65 (11.15) nmol/L. The mean (SD) for thyroid function test was 5.37 (44.16) mmol/L for thyroid-stimulating hormone, 1.48 (1.49) ng/dL for free thyroxine (FT4), and 2.69 (0.70) nmol/L for free triiodothyronine (FT3). Most of the participants were euthyroid (63.8%), but 28.6% had hypothyroidism and 7.7% had hyperthyroidism. The accuracy tests of ACR TI-RADS in relation to TBSRTC, were sensitivity (87.8%), specificity (65.2%), positive predictive value (29.8%), and negative predictive value (97%). The area under the curve = 0.590, 95% CI = 0.530–0.650, p ˂ 0.006. CONCLUSION: ACR TI-RADS is a simple, practical, and reliable scoring system for assessing thyroid nodule; it has a better overall diagnostic performance and the ability to exclude unnecessary FNAC with high negative predictive value.

A comparative study between conventional and the Bethesda System for Reporting Thyroid Cytology of 240 cases.

Thyroid nodule is a common disorder of thyroid. Despite their benign nature, they can be associated with multiple pathologic conditions including thyroid cancer. Fine-needle aspiration plays an essential role in evaluating thyroid nodules. The Bethesda System for Reporting Thyroid Cytology (TBSRTC) has attempted to standardize reporting and cytological criteria in aspiration smears. The aim of this study is to compare the conventional and TBSRTC and to compare and correlate the cases with histological findings wherever available. The present study was a retrospective study undertaken in the department of pathology from January 2018 to December 2018 to access the validity of TBSRTC considering histopathology as the gold standard. May Grünwald Giemsa and Papanicolaou stained thyroid FNA smears of 240 patients were collected which were reported by the conventional system for reporting thyroid cytology and also categorized as per current Bethesda nomenclature for thyroid cytology. Diagnosis of both the reporting systems was then compared and correlated with the histological diagnosis wherever possible. A total of 240 cases were examined on cytology, out of which histopathological correlation was possible in 110 cases. For benign thyroid lesions, sensitivity and specificity with conventional system were 69.91% and 40.25%, respectively, while with TBSRTC, sensitivity and specificity were 84.04% and 29.94%, respectively. Sensitivity and specificity of conventional system for malignant thyroid lesions were 58.56% and 69.91%, respectively, while with TBSRTC, sensitivity and specificity were 73.69% and 95.12%, respectively. The Bethesda system found to be highly sensitive for benign thyroid lesions and highly specific for malignant thyroid lesions as compared to the conventional method of reporting of thyroid cytology. Bethesda system was found to be superior for reporting thyroid cytology over the conventional system of reporting for thyroid cytology.

Non-Invasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features Is Not a Cytological Diagnosis, but It Influences Cytological Diagnosis Outcomes: A Systematic Review and Meta-Analysis

Background: A low-risk thyroid tumour, non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) was introduced in 2016. NIFTP criteria require a thorough histological examination to rule out capsular and lymphovascular invasion, which denies the possibility of preoperative cytological diagnosis. Nevertheless, since the adoption of the new entity, the cytology of NIFTP has been a subject of interest. Objectives: The present systematic review and meta-analysis investigate the cytological diagnosis of NIFTP. Method: An online PubMed literature search was conducted between March 1, 2020, and June 30, 2020, for all original articles considering the cytology of histologically proven NIFTP. The studies including data on fine needle aspiration specimens classified by The Bethesda System for Reporting Thyroid Cytology (TBSRTC) categories, risk of malignancy (ROMs) in the TBSRTC categories, and cytomorphological features of NIFTP were included in the meta-analysis. Non-English studies and case reports were excluded. The data were tabulated and statistical analysis was performed with Open Meta-Analyst program. Results: Fifty-eight studies with a total of 2,553 NIFTP cases were included in the study. The pooled prevalence of NIFTP cases was calculated among 25,892 surgically resected cases from 20 studies and the results show that NIFTP consisted 4.4% (95% confidence interval [CI]: 3.5–5.4%) of all cases. Most of the NIFTP cases (79.0%) belonged to the intermediate categories of TBSRTC. The pooled distribution of NIFTP cases in each TBSRTC category was 1.3% (95% CI: 0.8–1.7%) in non-diagnostic (ND), 8.9% (95% CI: 6.9–10.8%) in benign, 29.2% (95% CI: 25.0–33.4%) in atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS), 24.2% (95% CI: 19.6–28.9%) in follicular neoplasm (FN), 19.5% (95% CI: 16.1–22.9%) in suspicious for malignancy (SM), and 6.9% (95% CI: 5.2–8.7%) in malignant. Compared to pre-NIFTP era, the pooled risk differences of ROM were reduced by 2.4% in ND, 2.7% in benign, 8.2% in AUS/FLUS, 8.2% in FN, 7.3% in SM, and 1.1% in the malignant category. The cytomorphological features of NIFTP were similar to follicular variant of papillary thyroid carcinoma (FVPTC) but lesser to papillary thyroid carcinoma (PTC). Conclusions: Based on our results, NIFTP remains a histological diagnosis. Although cytomorphological features cannot be used in differentiating NIFTP from FVPTC, they may guide in separating NIFTP from PTC. Features such as papillae, microfollicles, giant cells, psammoma bodies, and the amount of papillary-like nuclear features should be taken into account when suspicious of NIFTP. NIFTP should not have papillae or psammoma bodies, and giant cells were rarely observed.

A correlation study between thyroid imaging report and data systems and the Bethesda system for reporting thyroid cytology with surgical follow‐up‐ an ultrasound‐trained cytopathologist's experience

Thyroid Imaging Reporting and Data Systems (TI-RADS) including a modified system (M TI-RADS) and American College Radiology (ACR) TI-RADS are introduced. Correlation studies between both TI-RADSs and The Bethesda System for Reporting Thyroid Cytology (TBSRTC) for Ultrasound-guided fine-needle aspiration (US-FNA) cases with surgical follow-up (SFU) are presented. Three hundred and forty six thyroid US-FNA cases performed at the US-FNA clinic of Stony Brook University Hospital by an Ultrasound-trained interventional Cytopathologist between December 1, 2014 to February 28, 2018 were reviewed. All ultrasound images from 346 cases were evaluated and assigned M TI-RADS scores based on ultrasound features present in Table 1. One hundred and fifty four cases from Dcember 1, 2014 to February 28, 2016 were assigned scores using ACR TI-RADS.TBSRTC category along with SFU data was collected and correlated with both TI-RADS scores by using Pearson's correlation coefficient (r). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy for M TI-RADS and TBSRTC were also calculated using SFU diagnosis as a gold standard. McNemar test was applied to evaluate the significance of the difference between M TI-RADS and TBSRTC. Based on 346 thyroid nodules studied, the overall r-value between M TI-RADS scores and TBSRTC categories is 0.465. The r-values between Composition, Echogenicity, Shape, Margin, Echogenic foci, the summary points, and the converted TR level of ACR TI-RADS and TBSRTC are 0.145, 0.042, 0.259, 0.310, 0.405, and 0.379, respectively. Fifty (14.5%) cases have SFUs. Considering TI-RADS 5&6 and TBSRTC 5&6 as positives, and TI-RADS 2 and TBSRTC 2 as negatives, the Sensitivity, Specificity, PPV, NPV, and accuracy are 96%, 53%, 76%, 89%, 79% for TI-RADS vs 100%, 93%, 96%, 100%, 97% for TBSRTC, respectively (P = .038). The data for indeterminate cases are summarized. Both TI-RADSs could be helpful to a moderate degree. M TI-RADS appeared to correlate to TBSRTC slightly better than that of ACR TI-RADS. TBSRTC is significantly more accurate than M TI-RADS for the majority of determined cases.

The Bethesda System for Reporting Thyroid Cytology (TBSRTC): From look‐backs to look‐ahead

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) was formalized in October 2007 by experts in thyroidology at the National Institute of Health in Bethesda, Maryland. The first edition of the TBSRTC book was published in 2010 and the second edition in 2018. The TBSRTC is widely employed in cytology practices in the United States and has also served as a model for similar tiered classification schemes for reporting thyroid cytopathology specimens. The tremendous success of TBSRTC cannot be underscored, it has provided a diagnostic framework which is well aligned with the present and the future of thyroid nodule management.

Comparison of the Bethesda system classification and postoperative cytology of thyroid nodules: A single center experience

Objective: Recent American Thyroid Association Guideline emphasizes that identifying the institutional malignancy risks for each Bethesda category is mandatory to achieve more accurate preoperative diagnosis in thyroid nodules. Aim of this study is to compare the preoperative fine needle aspiration biopsy (FNAB) and postoperative pathology results in a single institution in the era of the Bethesda System for Reporting thyroid Cytology (TBSRTC). Methods: The data of the patients who underwent FNAB and thyroidectomy between 2012 and 2018 were collected retrospectively. Patients who had available TBSRTC classification were included in the study. The malignancy risk of each TBSRTC classification was calculated. Results: One-hundred and forty-five patients were included. The mean age was 45.9±13.6. Preoperative FNAB categorization was TBSRTC I in 3 (2.1%) patients, TBSRTC II in 47 (32.4%) patients, TBSRTC III 16 (11%) patients, TBSRTC IV in 14 (9.7%) patients, TBSRTC V in 29 (20%) and VI in 36 (24.8%) patients. Postoperative pathology revealed malignancy in 66 (45.5%) of the patients. The malignancy risk was 33.3% in TBSRTC I, 4.3% in TBSRTC II, 31.3% in TBSRTC III, 42.9% in TBSRTC IV, 62.1% in TBSRTC V and 94.4% in TBSRTC VI categories. Conclusion: Our results were conformable with the malignancy risks reported by TBSRTC. Larger studies should be performed to validate and endorse nationwide standardization of the Bethesda system.

Application of American College of Radiology Thyroid Imaging Report and Data System (ACR TI-RADS) and its Correlation with The Bethesda System for Reporting Thyroid Cytology (TBSRTC) - An Interventional Cytopathologist's Experience

Application of American College of Radiology Thyroid Imaging Report and Data System (ACR TI-RADS) and its Correlation with The Bethesda System for Reporting Thyroid Cytology (TBSRTC) - An Interventional Cytopathologist's Experience

Thyroid fine needle aspiration reporting rates and outcomes before and after Bethesda implementation: A single-center experience over 8 years

Aimː To evaluate data from our hospital system before and after the implementation of the Bethesda System for Reporting Thyroid Cytology (TBSRTC) and comparison of our data with the previously published studies. Methods: Seven hundred seventy-one patients with thyroid nodules who underwent fine needle aspiration biopsy (FNAB) and surgery at our institution were analyzed retrospectively. FNAB results were divided into two parts in terms of the period they related to: pre-TBSRTC (between 2005 and 2010) and TBSRTC (between 2011 and 2013). Results: 341 FNAB were applied in the period of TBSRTC. Of the 341 FNAB, 53(16%) were non diagnostic, 82(24%) were benign, 62(18%) were atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS), 28(8%) were follicular neoplasms and/or suspicion of follicular neoplasms (FN/SFN), 95(28%) were suspicion for malignancy (SuspM), and 21(6%) were malignant. Rates of malignancy reported on follow-up histopathological examination were non diagnostic in 11%, benign in 4.9%, AUS/FLUS in 23%, FN/SFN in 32%, SuspM in 44%, and malignant in 95.3%. Conclusions: In this study, the distribution of cases in TBSRTC categories and malignancy rates, differed from, recommended by TBSRTC and some studies. Implementation of TBSRTC did significantly affect our institution’s reporting rates.

Deep neural networks could differentiate Bethesda class III versus class IV/V/VI.

Ultrasound (US) is the most commonly used radiologic modality to identify and characterize thyroid nodules. Many nodules subsequently undergo fine needle aspiration to further characterize the nodule and determine appropriate treatment. The fine needle aspirate is most commonly classified using the Bethesda System for Reporting Thyroid Cytology (TBSRTC). It can sometimes be difficult to differentiate Bethesda class III lesions (atypia of undetermined significance/follicular lesion of undetermined significance) from Bethesda class IV, V and VI (malignant nodules). However, differentiation is important as clinical management differs between the two groups. The purpose of this study was to introduce machine learning methods to help radiologists differentiate Bethesda class III from Bethesda class VI, V and VI lesions. The authors collected 467 thyroid nodules with cytopathology results. US features were summarized using the 2017 ACR (American College of Radiology) Thyroid Imaging Reporting And Data System (TIRADS). Machine learning models [logistic regression, gradient boost, support vector machine (SVM), random forest and deep neural networks (DNN)] were created to classify Bethesda class III vs class IV/V/VI. DNN outperformed other machine learning classifiers and obtained the highest accuracy and specificity to classify thyroid nodules as either Bethesda III or IV/V/VI nodules using multiple US features. Machine learning/deep learning approaches could help differentiate Bethesda III nodules from IV/V/VI using US features which may benefit treatment decisions.

A Correlation Study between Thyroid Imaging Report and Data System (TI-RADS) and The Bethesda System for Reporting Thyroid Cytology (TBSRTC) with ThyroSeq Test and Surgical Follow-Up - An Interventional Cytopathologist's Experience

A Correlation Study between Thyroid Imaging Report and Data System (TI-RADS) and The Bethesda System for Reporting Thyroid Cytology (TBSRTC) with ThyroSeq Test and Surgical Follow-Up - An Interventional Cytopathologist's Experience

The Bethesda System for Reporting Thyroid Cytopathology Explained for Practitioners: Frequently Asked Questions.

The recent update of The Bethesda System for Reporting Thyroid Cytology (TBSRTC) is a very important development in the evaluation of thyroid nodules. Clinical experience and scientific literature both show that practitioners performing thyroid fine-needle aspiration are accustomed to basing the clinical management of patients on reports using TBSRTC. Specifically, clinicians are familiar with the percent risk of malignancy corresponding to each TBSRTC diagnostic category (DC), as well as with the respective recommendation for clinical management. However, most clinicians are much less familiar with the specific considerations that lie between a given DC, on the one end, and the respective risk of malignancy and associated management recommendation, on the other end. A deeper understanding of the system can enlighten the clinician's thinking about the specific nodule under examination and can guide the decision-making process in a more meaningful way. Such an understanding can only be developed via close two-way communication between cytopathologists and clinicians. Through this type of interaction in the authors' tertiary medical center, recurring issues of particular importance for clinical practice were identified, which are reported here in the form of 16 frequently asked questions posed by the clinician to the cytopathologist. For each frequently asked question, an answer is provided based on the literature, the authors' experience, the new version of TBSRTC, and the new World Health Organization classification of tumors of endocrine organs.

A follow-up study on thyroid aspirates reported as atypia of undetermined significance/follicular lesion of undetermined significance and follicular neoplasm/suspicious for follicular neoplasm: A multicenter study from the Arabian Gulf region.

This is a multicenter study which was conducted to evaluate the follow-up on thyroid aspirate cases with atypia of undetermined significance/follicular cells of undetermined significance (AUS/FLUS) and follicular neoplasm or suspicious for follicular neoplasm (FN/SFN) using the Bethesda system for reporting thyroid cytology (TBSRTC). The archival materials of all thyroid fine-needle aspirates over a 5-year period were retrieved from 3 institutions in the Arabian Gulf Region. All cytology slides and follow-up material for cases interpreted as AUS/FLUS and FN/SFN were reviewed. The revised diagnoses and follow-up were recorded. Analysis of risk of malignancy was calculated for the 2 entities. A total number of 2592 thyroid fine-needle aspirates were performed, out of which AUS/FLUS was found in 115 (4.4%) while FN/SFN in 39 (1.5%). Follow-up by surgery or repeat FNA was conducted on 42 (27%) and 10 (7%) patients on these 2 categories, respectively. The risk of malignancy was found to be 29% and 45%, respectively. The risk of malignancy for AUS/FLUS and FN/SFN are 29% and 45%, respectively. This risk of malignancy in our study is on the higher range of that reported in the literature.

The Bethesda System for Reporting Thyroid Cytopathology: proposed modifications and updates for the second edition from an international panel

The Bethesda System for Reporting Thyroid Cytology (TBSRTC) was proposed in 2007 at the National Cancer Institute Thyroid Fine Needle Aspiration State of the Art and Science » Conference held in Bethesda, Maryland. The aim was to address the inconsistent and sometimes confusing reporting terminologies used for thyroid FNA throughout the world. The TBSRTC consists of 6 diagnostic categories, each associated with an implied risk of malignancy that translates directly into a clinical management algorithm. Since the publication of the TBSRTC cytology Atlas in January 2010, considerable experience has been gained regarding its application in cytology practice, clinical impact, and limitations. In conjunction with the International Academy of Cytology (IAC), an international panel composed of sixteen cytopathologists and an endocrinologist with special interest in thyroid cytology, including several co-authors of the 2010 TBSRTC Atlas, was created to: 1) analyze the current worldwide impact of TBSRTC, 2) report on the current state of TBSRTC based upon a review of the published literature, and 3) provide possible recommendations for a future update of TBSRTC. Herein, we summarize the panel's deliberations and key recommendations that our panel hopes will be useful during the preparation of the second edition of TBSRTC.

The impact of using the Bethesda System for reporting thyroid cytology diagnostic criteria on the follicular lesion of undetermined significance category

The Bethesda System for Reporting Thyroid Cytology (TBSRTC) refines the definition of and provides specific diagnostic criteria for the category of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS). This study was conducted to review our institutional experience with thyroid nodules interpreted as FLUS using TBSRTC diagnostic criteria. A SNOMED (Systemized Nomenclature of Medicine) search of the electronic pathology database in our institution for the period of January 2011 to June 2012 was conducted to identify thyroid aspirates previously interpreted as FLUS using TBSRTC diagnostic criteria. Allcases were followed for at least 6 months. Follow-up information including clinical/imaging monitoring, repeat fine-needle aspiration, and/or subsequent surgical intervention, along with the corresponding cytologic diagnosis and/or histologic diagnosis were collected for each case. Cytology-histology concordance was evaluated for aspirates with surgical follow-up. We identified a total of 122 FLUS cases and follow-up information was available in 100 cases. Among the 100 cases, 31 appeared clinically stable and showed no size change on ultrasonographic imaging; 9 were reclassified as benign non-neoplastic by a repeat fine-needle aspiration; and 60 received surgical treatments. The follow-up histology revealed 26.7% (16 of 60) papillary thyroid carcinoma, 25% (15 of 60) follicular adenoma, and 48.3% (29 of 60) non-neoplastic nodules (nodular hyperplasia or lymphocytic thyroiditis). Compared with historical control subjects from our institution, the current study demonstrates that adhering to TBSRTC diagnostic criteria yields a higher prediction of histology-proven neoplasia (25% versus 14.9%) and malignancy (26.7% versus 9.2%) for the FLUS category.

An Audit of Atypical Thyroid FNA Using The Bethesda System for Reporting Thyroid Cytology (TBSRTC) in Regional NSW, Australia

An Audit of Atypical Thyroid FNA Using The Bethesda System for Reporting Thyroid Cytology (TBSRTC) in Regional NSW, Australia

The Bethesda Terminology for Reporting Thyroid Cytopathology: From Theory to Practice in Europe

Objectives: A 2007 conference held at the National Cancer Institute, Bethesda, Md., USA, proposed a new terminology for classifying the results of thyroid fine-needle aspiration (FNA) – The Bethesda System for Reporting Thyroid Cytology (TBSRTC). The need to standardize thyroid FNA terminology was emphasized during the 35th European Congress of Cytology in 2009. An interobserver review study to assess the new terminology for analyzing the results of thyroid FNA was organized by the scientific committee of the European Federation of Cytology Societies. Study Design: Four experts in thyroid FNA examined and classified 116 FNAs according to the 6 levels of TBSRTC which are: nondiagnostic (ND); benign; atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS); follicular neoplasm/suspicious for a follicular neoplasm (FN/SFN), with those of Hürthle cell type reported as follicular neoplasm, Hürthle cell type/suspicious for a follicular neoplasm, Hürthle cell type (FNHCT/SFNHCT); suspicious (SUS), and malignant. Results: The total consensus was 62.1%; the cytopathologists disagreed on 44 cases, including 8 cases of AUS/FLUS and 18 of FN/SFN; 59% of the cases had no consensus. They agreed on 73 and 80% of the cases classified as benign and malignant, respectively, and on 58.3% of the SUS cases. The percentage of no consensus for each expert was between 32 and 39%. Conclusions: Disagreement regarding the use of TBSRTC terminology for classifying the results of thyroid FNA mainly occurred in the most-often criticized categories of AUS/FLUS and FN/SFN.

Atypical Follicular Cells with Equivocal Features of Papillary Thyroid Carcinoma Is Not a Low-Risk Cytologic Diagnosis

Objective: To determine whether or not significant differences in the risk of malignancy exist between subgroups of atypical follicular cells in The Bethesda System for Reporting Thyroid Cytology (TBSRTC) in patients who underwent surgical resection. Study Design: Between 2004 and 2009, consecutive thyroid fine-needle aspirates at our institutions with a cytologic diagnosis of ‘atypical follicular cells’ were retrieved and subclassified using the diagnosis and diagnostic comment as: (1) atypical follicular cells with equivocal features of papillary carcinoma [cannot exclude papillary thyroid carcinoma (PTC)] and (2) atypical follicular cells, other patterns. The risks of malignancy for excised nodules were calculated and comparisons were made between these subgroups. Categorical analysis was performed using a 2-tailed Fisher’s exact test, and p < 0.05 was considered statistically significant. Results: A total of 7,072 thyroid fine-needle aspiration cases were retrieved, with 1,542 (21.8%) having a histologic follow-up. There were 222 (3.1%) cases of ‘atypical follicular cells’, with 127 (57.2%) having a histologic correlation and 33 having confirmed malignancies. Atypical follicular cells, cannot exclude PTC, have a significantly higher risk of malignancy than atypical follicular cells, other patterns (45.8 vs. 13.9%, p < 0.01). Conclusions: Atypical follicular cells with equivocal features of papillary carcinoma is not a low-risk cytologic diagnosis.

The Bethesda System for Reporting Thyroid Cytopathology: Interpretation and Guidelines in Surgical Treatment

(1) The aim of this study is to assess the efficacy of The Bethesda System for Reporting Thyroid Cytology (TBSRTC) in accurate prediction of thyroid lesions on fine needle aspiration (FNA). (2) To appraise the surgeon with guidelines for adequacy of samples, and interpretation of FNA reports with TBSRTC and hence aiding them in surgical decision making. Five hundred and sixty four FNAs were done on patients with thyroid swellings in the department of Pathology and reported using TBSRTC guidelines. In cases where surgery was done, histopathological report was correlated. Using TBSRTC the commonest cytological diagnosis was benign-Hashimotos thyroiditis followed by benign follicular nodule. TBSTRC reduces inter-observer variability in reporting thyroid FNAs and provides good communication between the surgeon and pathologist. It also implicates guidelines for cancer risk and clinical management to the surgeons, thus avoiding unnecessary surgery.