Incidence and malignancy rates of diagnoses in the bethesda system for reporting thyroid aspiration cytology: an institutional experience

Evaluation of the Efficacy of Thyroid Imaging Reporting and Data Systems Classification in Risk Stratification and in the Management of Thyroid Swelling by Comparing It With Fine-Needle Aspiration Cytology and Histopathological Examination

BACKGROUND

Thyroid nodules are a common clinical challenge, with a significant proportion being cancerous. Fine-needle aspiration cytology (FNAC) is widely used for diagnosis but has limitations. Ultrasound has emerged as a promising tool for distinguishing between benign and malignant nodules. This study aims to compare the diagnostic accuracy of ultrasonography (USG) and FNAC in diagnosing malignant thyroid swelling using postoperative histopathological examinations as the gold standard.

METHOD

A diagnostic accuracy study was conducted over 1.5 years at Rajendra Institute of Medical Sciences, Ranchi, India. A total of 132 patients with thyroid swellings were included. Patients underwent USG and FNAC, and 99 patients subsequently underwent surgery and histopathological examination. Statistical analysis was performed to evaluate the performance of USG and FNAC, including sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

The study encompassed 132 patients, predominantly 94 (71.21%) females. Most patients, i.e., 76 out of 132 (57.58%), were aged 30-50 years, with an average age of presentation at 41 years. Socioeconomic status revealed 120 (90.9%) belonging to Classes II and III. USG and FNAC exhibited sensitivities of 77.4% and 90.3%, specificities of 94.1% and 98.5%, and accuracies of 88.9% and 96.0%, respectively. FNAC demonstrated superior diagnostic performance metrics compared to USG, with higher PPV and NPV, indicating its stronger ability to correctly identify true-positive cases. Ultrasound features and FNAC findings showed significant associations with biopsy results, reaffirming their utility in diagnosing thyroid nodules.

CONCLUSION

FNAC emerged as a highly accurate diagnostic tool for distinguishing between benign and malignant thyroid nodules, outperforming USG. Understanding demographic and clinical characteristics can aid in the timely diagnosis and management of thyroid disorders. Further research is warranted to enhance diagnostic algorithms and optimize patient care in resource-constrained settings.

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.

Correlation of Thyroid Fine Needle Aspiration Biopsy With Histopathological Results

Introduction Fine needle aspiration biopsy (FNAB) is an effective method used in the differential diagnosis of thyroid nodules. The Bethesda system has contributed to the determination of clinical approaches by bringing standardization to cytopathology reporting. However, the rate of cytological-histological incompatibility varies between 10% and 30%. Results differ according to clinics in the literature. These results create a need to reevaluate the efficacy and safety of fine needle aspiration biopsy. In this study, we aimed to evaluate the diagnostic accuracy of FNAB of thyroid nodules by correlating the cytopathology results of FNAB with the results of postoperative histopathology. Methods In this retrospective study, thyroid FNAB results and postoperative histopathology results of patients who underwent thyroidectomy operations in our clinic between January 2018 and December 2021 were compared. Accuracy, sensitivity (Sn), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), false positive rate (FPR), and false negative rate (FNR) were calculated. Cases with nondiagnostic FNAB results were excluded from the calculations. FNAB results with a follicular neoplasm/suspicious for a follicular neoplasm (FN/SFN) and suspicious for malignancy were included in the malignant group. Results A total of 304 patients were included in the study. The male/female ratio was 1:3.3. As a result of the study, malignancy was detected histopathologically in 47 (15.46%) patients. The commonest malignancy detected was papillary carcinoma. According to the Bethesda system, the results were evaluated in six categories. The incidence of malignancy in the Bethesda categories were 0%, 4%, 40%, 69.2%, 100%, and 100%, respectively. Accordingly, the specificity and sensitivity of FNAB for detecting malignancy were 98.7% and 66.6%, respectively. The accuracy was 93.5%. The false positive rate, false negative rate, positive predictive value, and negative predictive value were 1.20%, 33.3%, 91.4%, and 93.8%, respectively. Conclusion Thyroid FNAB is an effective method used with satisfactory reliability in the differential diagnosis of malignancies of thyroid nodules. Still, it has some limitations. This article demonstrates higher rates of malignancy in Bethesda categories III and IV. Therefore, clinical approaches are gaining importance in these categories.

Study of Fine Needle Aspiration Cytology (FNAC) of Thyroid Gland According to the Bethesda System

BACKGROUND

 Fine needle aspiration cytology (FNAC) of thyroid gland is a powerful diagnostic tool for thyroid nodules. The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) classifies thyroid FNAC findings into six categories. It is a standardized, simple, and convenient method of reporting which also provides guidelines for management.

AIMS AND OBJECTIVES

 To study the cytomorphology of thyroid lesions and classify them as per TBSRTC. Determine the epidemiology and distribution of various thyroid lesions in our tertiary care hospital. Correlation of cytopathology with histopathological diagnosis in cases which were operated in our hospital.

METHODS AND MATERIAL

 This is a prospective analytical study of 105 patients with clinically enlarged thyroid gland presenting at G.K. General Hospital, Bhuj during July 2018 to August 2020. FNAC smears of these patients were studied and correlated with histopathology wherever available.

RESULTS

 Out of a total 105 cases, 94 were non-neoplastic, eight were neoplastic, and three were unsatisfactory for evaluation. There were 94 cases in the benign category (category II), with colloid goiter being the most common cytological diagnosis (38 cases). There were no cases in categories III and V, respectively. On cytology, two cases in category IV were diagnosed as follicular neoplasm. Category VI had six cases comprising papillary carcinoma of thyroid (five cases) and medullary carcinoma of thyroid (one case). Out of a total 105 cases, 55 patients were operated in our center and hence their cytopathological findings were correlated with histopathological findings. Out of 55 operated cases, 45 cases (81.8%) had benign lesion and 10 cases (18.2%) were malignant. The sensitivity of FNAC was 70% and specificity was 100%.

CONCLUSIONS

 Thyroid cytology proves to be a reliable, simple, and cost-effective first-line diagnostic procedure with high patient acceptance and with rare, usually easily treated and not life-threatening complications. The Bethesda system is very useful for a standardized and reproducible system of reporting thyroid FNAC. It satisfactorily correlates with the histopathological diagnosis and helps in comparing results amongst various institutes.

Reproducibility of Cytomorphological Diagnosis and Assessment of Risk of Malignancy of Thyroid Nodules Based on the Bethesda System for Reporting Thyroid Cytopathology: A Tertiary Cancer Center Perspective

Introduction

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) was introduced for unifying the terminology and morphologic criteria along with the corresponding risk of malignancy, leading to more consistent management approaches. The aim of this study was to study the utility and reproducibility of TBSRTC in reporting thyroid cytology in a referral cancer center.

Methods

The fine-needle aspiration (FNA) of all thyroid nodules were included for a period of 5 years, from January 2016 to December 2021, in this cancer center. They were retrospectively reviewed and recategorized according to TBSRTC by two experienced pathologists. Cytohistopathological correlation was done for the cases which underwent surgical resection.

Results

522 fine-needle aspiration cytology (FNAC) of thyroid swellings were evaluated and categorized according to TBSRTC. There was agreement in the cytological diagnosis of 512 cases, of which 260 (50.78%) were benign lesions, 189 (36.91%) were malignant, 5 (0.97%) were unsatisfactory/nondiagnostic, 41 (8.01%) were follicular neoplasm/suspicious for neoplasm, 13 (2.53%) were suspicious for malignancy, and 4 (0.78%) cases were reported as atypia of undetermined significance. Two cytopathologists were in agreement in 512 cases (98%) of cases. Almost complete concordance was noted in the malignant (99%) and benign categories (98%). Disagreement was seen in 10 cases. Histological follow-up was available in 201 cases with an overall malignancy rate of 62.68% (126/201).

Conclusion

TBSRTC proved to be a very simple and effective reporting system for thyroid FNAC, especially in the setting of a cancer center. This enables proper triaging of cases with thyroid masses into those who require surgical intervention and those who can avoid it, thereby preventing unnecessary morbidity.

The Bethesda System for Reporting Thyroid Cytopathology: Validating at Tribhuvan University Teaching Hospital

Introduction  Fine needle aspiration cytopathology (FNAC) is widely used for the stratification of thyroid nodules.

Objective  The objective of the present study is to validate FNAC reporting based on The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) at our institution and to calculate the risk of malignancy in each category.

Methods  This was a descriptive cross-sectional study conducted jointly at the Department of Ear, Nose and Throat and at the Department of Pathology for a period of 1.5 years (May 2018 to November 2018). All cases presenting with thyroid swelling in the outpatient department were investigated with ultrasonography (USG) of the neck, thyroid function test, and FNAC. All FNAC reporting was done according to TBSRTC.

Results  A total of 134 thyroidectomies were performed during the study period. The female to male ratio was 5.3:1. The age ranged from 11 to 74 years old. with a mean age of 51 years old. The FNAC has a specificity of 84.9%, a sensitivity of 89.4%, a positive predictive value of 86.4%, a negative predictive value of 88.2%, and an accuracy of 87.3% in detecting thyroid cancer. The implied risk of malignancy (ROM) in Bethesda II, III, IV, V and VI is 11.7%, 25%,40%,76.6% & 96%, respectively.

Conclusion  The four studied categories had a ROM comparable to other studies, except for the Bethesda III category. Further studies with larger sample sizes and with the use of USG guidance for the aspiration from the thyroid swelling may give better results by reducing the number of false negative and false positive cases.

Application of the Bethesda system for reporting thyroid cytopathology for classification of thyroid nodules: A clinical and cytopathological characteristics in Bhutanese population

INTRODUCTION

The existence of baseline data on the spectrum of thyroid nodules in Bhutanese patients is unknown. Fine-needle aspiration cytology (FNAC) is regarded as the gold standard diagnostic test for pre-op assessment of thyroid lesions.

MATERIALS AND METHODS

We conducted a retrospective study, involving 765 patients who underwent FNAC of the thyroid gland, at Jigme Dorji Wangchuck National Referral Hospital, Thimphu, between January-2018 to December-2020. We aimed to assess the cytomorphological spectrum of thyroid nodules, classify them as per The Bethesda system for reporting thyroid cytopathology (TBSRTC), assess risk of malignancy (ROM), and evaluate the accuracy of FNAC in diagnosing thyroid malignancy.

RESULTS

Colloid nodule (37.4%) and papillary thyroid carcinoma (4.2%) constituted the majority of benign and malignant cytological diagnoses, respectively. According to TBSRTC, majority of the cases (82.0%) fell under the Bethesda II category. Bethesda III was the least common (1.4%) category. As compared to histopathological diagnosis; the sensitivity, specificity, positive and the negative predictive values of FNAC in diagnosing thyroid malignancy were 90.0%, 93.3%, 93.10%, and 90.32% respectively. The ROM increased concurrently with the grade of the Bethesda category and was more or less close to the ROM reference range, published in the TBSRTC.

CONCLUSION

Benign thyroid nodules (82.0%) constituted a majority of thyroid nodules in Bhutanese patients. FNAC was found to be reliable in detecting thyroid malignancy. From the literature, TBSRTC was found to be a more convenient method for reporting thyroid cytology. Henceforth, as most institutes, we plan to implement TBSRTC for reporting thyroid cytopathology.

The combination of ACR-Thyroid Imaging Reporting and Data system and The Bethesda System for Reporting Thyroid Cytopathology in the evaluation of thyroid nodules-An institutional experience

BACKGROUND

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) is widely utilised by cytopathologists. The American College of Radiology (ACR) has also proposed a thyroid imaging reporting and data system (TIRADS) to classify thyroid nodules and guide their selection for fine needle aspiration (FNA). The current study aimed to analyse the usefulness of TBSRTC in thyroid cytology reporting, to examine its histological correlation with TIRADS, and to compare the management of lesions in each cytological category in our institute to the TBSRTC recommendations.

MATERIALS AND METHODS

A retrospective study was performed on all thyroid FNAs from a 2-year period at a tertiary care centre. Histological correlations of TBSRTC and ACR TIRADS were examined for cases with surgical follow-up, and the risk of malignancy in each TBSRTC category, and sensitivity and specificity of FNA and TIRADS, were calculated.

RESULTS

A total of 337 thyroid FNAs were examined, with histological follow-up in 99 cases. Risk of malignancy in categories I-VI was 9.5%, 2.3%, 0.0, 8%, 87.5% and 100.0%, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of FNA were 60.0%, 99.0%, 85.7%, and 97.5%, respectively, while those values for thyroid ultrasound were 90.3%, 72.2%, 92.9% and 65%, respectively.

CONCLUSION

The study substantiates the usefulness of TBSRTC in arriving at a more precise diagnosis. Hurthle cell lesions with atypia were the common cause of misdiagnosis. The combination of TIRADS and TBSRTC aids in better stratification of thyroid nodules and in decision making for management of lesions.

Validating the 'CUT score' risk stratification tool for indeterminate thyroid nodules using the Bethesda system for reporting thyroid cytopathology

PURPOSE

Managing intermediate thyroid nodules remains challenging. The CUT score is an Italian metanalysis-based cytologic (SIAPEC-IAP) scoring system, designed to assist clinicians. However, it was never evaluated against the Bethesda system for reporting thyroid cytopathology (BSRTC). This study aims to validate its utility for BSRTC III and IV nodules in a non-Italian population.

METHODS

We collected all BSRTC III and IV thyroid nodules with a documented final pathology between 2010 and 2020. We calculated the C + U components of the CUT score using retrospective clinical (C) data collection and reevaluation of preoperative sonography (U) examination. The cytology (T) component which originally referred to the five-tiered SIAPEC-IAP cytologic classification was replaced by the corresponding BSRTC categories. Optimal test performances were calculated using receiver operating characteristic (ROC) curve analysis. Data were analyzed twice with considering of NIFTP as benign and as malignant.

RESULTS

After exclusions, 62 nodules from 61 patients were included (50% BSRTC III, 50% BSRTC IV). Malignant nodules demonstrated a significantly higher C + U score compared with benign in both categories. The C + U cutoff value for BSRTC III was 5.25 (sensitivity and specificity of 69.23% and 66.67%, respectively, AUC = 0.72, p-value = 0.016), and 5.75 for BSRTC IV (sensitivity and specificity of 85.7% and 76.5%, respectively, AUC = 0.84, p-value < 0.001).

CONCLUSION

Our study suggests that the CUT score is applicable for both BSRTC III and IV nodules, and highlights the need for internal validations, since the cutoffs found were higher than previously reported.

Ultrasound-guided fine needle aspiration cytology and ultrasound examination of thyroid nodules in the UAE: A comparison

Background

Thyroid nodules are a common clinical finding and most are benign, however, 5–15% can be malignant. There is limited regional data describing the accuracy of ultrasound-guided fine needle aspiration (FNA) cytological examination compared to ultrasound examination of thyroid in patients who have undergone thyroid surgery.

Methods

A retrospective analysis of ultrasonographic (US) reports, FNA cytology reports and histopathology reports of 161 thyroid nodules presented at the endocrine center at Tawam hospital in Al Ain city, the United Arab Emirates during the period 2011–2019 was performed. US reports and images with FNA cytopathology reports and slides were reviewed by an independent radiologist and pathologist.

Results

In total, 40 nodules were reported as benign by US examination, while very low suspicious, low suspicious, intermediate suspicious and highly suspicious categories were reported in 21, 41, 14 and 45 nodules respectively. In addition, 68 nodules were reported as benign (Bethesda category II), while atypical follicular cells of unknown significance (Bethesda category III), follicular neoplasm (Bethesda category IV), suspicious for malignancy (Bethesda category V), and malignant (Bethesda category VI) categories were reported in 33, 9, 24 and 27 nodules respectively. The risk of malignancy for US benign nodules was 5%, while the risks of malignancy in very low suspicious, low suspicious, intermediate suspicious and highly suspicious nodules were 52%, 36%, 100% and 87%, respectively. The risk of malignancy for Bethesda category II was 3%, while the risks of malignancy in category III, IV, V and VI were 58%, 67%, 96% and 100%, respectively.

Conclusion

Thyroid FNA cytological examination and ultrasonography are key tools in predicting malignancy in thyroid nodules. Thyroid nodules with the diagnosis of Bethesda category III & IV run a high risk of malignancy thus more vigilance is required.

National differences in cost analysis of Afirma Genomic sequencing classifier

CONTEXT

Thyroid nodules of indeterminate cytology can be subjected to molecular testing such as the Afirma Genomic Sequencing Classifier (GSC), thereby minimizing the number of unnecessary diagnostic surgeries.

OBJECTIVE

This work aimed to evaluate and compare the cost of routine GSC testing of indeterminate thyroid nodules in different countries.

DESIGN, PATIENTS AND MAIN OUTCOME MEASURES

The cost of diagnostic hemithyroidectomy of indeterminate thyroid nodules was calculated by performing a Monte Carlo simulation cost analysis on a Markov decision-analytic model and then compared to that of GSC testing in the UK, Australia, USA, and Israel.

RESULTS

Assuming that patients are treated by surgical resection and routine GSC testing is performed for all nodules of indeterminate significance, we found the GSC test to be more cost effective compared with diagnostic hemithyroidectomy when malignancy rates of thyroid nodules are less than 22.6%-37.1%, depending on the country where the test is performed. Given the cost of a thyroidectomy in the UK, Australia and Israel, performing routine GSC tests on all Bethesda IV nodules is more expensive than routine diagnostic hemithyroidectomy and becomes cost effective for Bethesda III when the GSC cost is below 3,031-3,087 USD. In comparison, in the USA, higher cost of thyroidectomy makes the GSC test cost effective for Bethesda III nodules at its current cost, but not for Bethesda IV nodules where it becomes cost effective under the price of 3,031 USD.

CONCLUSIONS

Different molecular testing and surgical costs in different countries should be considered when performing cost analysis. In addition, since different medical centres have different malignancy rates, personalized in-house assessment of cost-effectiveness is warranted.

Incidence, Clinical Characteristics, and Histopathological Results of Atypia of Undermined Significance in a Tertiary Center in UAE

<b><i>Introduction:</i></b> Bethesda classification of thyroid nodules cytology is an agreed upon method of classifying thyroid nodules according to risk of malignancy. Among them, Bethesda class III (Atypia of Undetermined Significance, AUS) has been a topic of great controversy. The reported estimated risk of malignancy associated with it varies in different studies. Our study investigates the associated incidence of malignancy in a single tertiary center in UAE. <b><i>Methodology:</i></b> Data were retrospectively collected over a 10-year period from January 2009 till December 2018 for cytology diagnosis of AUS. Patient charts were reviewed for method of management. Surgical and histopathology records were reviewed to compare findings on cytology versus histopathology. <b><i>Results:</i></b> A total of 180 cases were diagnosed Bethesda III (AUS) with a mean age of 45.09 ± 14.7 years. One hundred cases (55.6%) of them underwent surgical resection, and histopathological diagnosis was obtained. Among the operated cases, 46 were benign and 54 were malignant. Papillary thyroid cancer was the most common malignancy, seen in 39 (72.2%) of cases, and follicular cancer was the second most common, seen in 13 (24.1%) cases. <b><i>Conclusion:</i></b> The findings highlighted in our study suggest a higher incidence of malignancy in Bethesda III category than previously reported. It also puts in question the utility and benefit behind keeping a time gap and repeating FNA as previously recommended.

Thyroid malignancy rates according to the Bethesda reporting system in Israel - A multicenter study

INTRODUCTION

The Bethesda System for Reporting Thyroid Cytopathology was developed in 2007 to facilitate an accurate, reproducible communication of thyroid fine-needle aspiration (FNA) interpretations between clinicians and cytopathologists and to serve as a guide for treatment. Based on large patient series, the system details the risk of malignancy for each category as well as a suggested management for each FNA result. Though this system has been widely adopted, there are only few studies to determine whether results are applicable for Israel.

METHODS

A multicenter, retrospective analysis of medical charts of all patients who underwent thyroid surgery between January 1st, 2012 and December 31st, 2016 in four medical centers in Israel was performed. Data was analyzed for the overall risk of malignancy for the Bethesda system groups as well as comparison between the different laboratories performing the test.

RESULTS

Records of 810 thyroidectomies in which preoperative cytological reports and final pathology were available and reviewed. The malignancy rates according to the Bethesda groups' I-VI for our cohort were: 27.8%, 17.6%, 41.4%, 41.4%, 86.9%, and 98.1% respectively. Similar results were seen when results were analyzed according to the different laboratories performing the tests.

CONCLUSIONS

Post-surgical review of all Bethesda groups had higher malignancy rates than those reported in the original report. These results indicate a difference in the malignancy rates for the different Bethesda system groups in Israel compared to those reported. Physicians are encouraged to use data validated for their own country or patients' community in addition to published values.

Outcomes of the Bethesda system for reporting thyroid cytopathology: Real-life experience

OBJECTIVE

The 2017 revised Bethesda System for Reporting Thyroid Cytopathology (BSRTC) included new malignancy rates for each category as well as new management recommendations. Here, we evaluate the malignancy rate and test performance for BSRTC categories in a middle-sized institution outside the United States (US).

DESIGN

Retrospective single centre case series with chart review.

PATIENTS

All patients who underwent thyroid surgery with a preoperative BSRTC between the years 2010 and 2018 at our institution.

MEASUREMENTS

In order to assess the malignancy rate for each BSRTC, all medical records were reviewed to collect demographics, nodule's size, BSRTC and final pathology.

RESULTS

Three hundred and sixty-four patients were included, with an overall malignancy rate of 34.3%. The malignancy rate for BSRTC categories I-VI was as follows: 13.3%, 5.1%, 25.0%, 24.4%, 91.3% and 95.2%, respectively. The most sensitive test was when BSRTC III-VI were evaluated (91%). Overall best performance (sensitivity, specificity, PPV, NPV and accuracy) was obtained when BSRTC V-VI were grouped together with a substantial decrease when adding BSRTC III-IV (90%, 97%, 94%, 95%, 95% vs, respectively, 91%, 73%, 62%, 95%, 79%, respectively).

CONCLUSIONS

Despite differences from the reported 2017 BSRTC malignancy rates, we demonstrated that the revised 2017 BSRTC management recommendations for thyroid nodules are also valid in smaller non-US centre, supporting its use globally.

Malignancy rates in thyroid nodules classified as Bethesda categories III and IV; a subcontinent perspective

BACKGROUND

Bethesda category III and IV thyroid nodules fall in the indeterminate risk of malignancy category. These nodules have been a relatively elusive entity to manage as previous studies have shown a wide variation in malignancy rates in different regions and institutions across the world. However, data from the subcontinent with regards to this is scarce.

AIM AND OBJECTIVE

This study aimed to determine the characteristics and malignancy rates of cytology proven Bethesda Category III and IV thyroid nodules and its association with clinical, histopathological and laboratory variables, in the regional population.

METHOD

A retrospective search was performed on all patients with thyroid nodules who presented to this hospital, from January 2011 to September 2018. Patients who had cytology proven Bethesda category III and IV thyroid nodules that underwent surgery were included in the study.

RESULTS

Malignancy in Bethesda Category III and Bethesda Category IV thyroid nodules was 29.6% and 47.1%, respectively. There was no significant association determined between malignancy rate and various clinical, histopathological, and radiological characteristics.

CONCLUSION

The malignancy rates in Bethesda category III and IV thyroid nodules in this study are significantly higher than that initially suggested by the Bethesda consensus publication but is comparable to international data present.

Thyroid cytology in Pakistan: An institutional audit of the atypia of undetermined significance/follicular lesion of undetermined significance category

INTRODUCTION

Fine needle aspiration cytology (FNAC), along with thyroid ultrasound, is an important tool in evaluation of thyroid nodules that helps in further management of these patients in making a decision of surgical intervention vs follow-up. The Bethesda System for Reporting Thyroid Cytopathology category III of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) has risk of malignancy (ROM) ranging from 5% to 15%. The aim of the present study was to describe the frequency of AUS/FLUS in thyroid gland FNACs and the surgical outcomes of these cases.

METHODS

The integrated laboratory management system retrieved the thyroid FNACs from 2010 to 2018 and subsequent surgical pathology specimens. For the AUS/FLUS cases, data regarding patient demographics, cytology and histological diagnoses were recorded. The results were tabulated as the overall frequency of AUS/FLUS in thyroid FNACs, cytohistological correlation (benign and malignant) and ROM.

RESULTS

Over a period of 9 years, 256 (10.9%) cases out of 2342 thyroid FNACs were reported as AUS/FLUS at our institution. Mean age was 43.5 years. The majority (70.3%) of patients were female. Seventy-two of 104 resection specimens (69.2%) were reported as benign and 32 cases (30.7%) had malignant diagnosis. Upper-bound ROM was 30.7% (32 cases with malignant diagnosis out of 104 resection specimens). Lower-bound ROM was calculated as 12.5% (32 cases with malignant diagnosis out of 256 total AUS diagnosis).

CONCLUSION

The AUS/FLUS category of thyroid cytology and associated ROM remain an evolving area. Individual institutions should monitor the frequency and include ROM in the dashboard indicators to remain within the recommended range.

Differences in cytopathologist thyroid nodule malignancy rate

OBJECTIVES

The accuracy of a cytological diagnosis obtained by fine needle aspiration is influenced by several factors including the technique used and the experience of both the aspirator as well as the cytologist. In this project we planned to evaluate the interobserver differences of thyroid nodule cytopathology in our medical centre.

METHODS

The study was conducted using retrospective pathology reports from a single academic centre from August 2013 to September 2017. We compared the sensitivity, specificity, negative and positive predictive values, malignancy rates, and accuracy of two cytopathologists who evaluated thyroid nodules.

RESULTS

We included 287 fine needle aspirations of thyroid nodules in the study. Approximately one fifth (18.5%) of patients had surgery and the rate of malignancy was 40%. There was a similar frequency of use of all thyroid Bethesda system (TBS) categories with the exception of TBS 3 (8.0% and 21.2%, P = .01). As a consequence, the malignancy rate was different in TBS 3 category (40% vs 17%, P = .545).

CONCLUSIONS

There are interobserver differences in the evaluation of thyroid nodules. Clinicians should be aware of such differences because they affect the malignancy rate in each TBS category.

Determining whether surgeons perform thyroid fine-needle aspiration as well as radiologists: an analysis of the adequacy and efficiency of ultrasound-guided fine-needle aspiration performed by newly trained head and neck surgeons and radiologists

Background

Ultrasound-guided fine-needle aspiration (FNA) cytology is a crucial diagnostic technique used to assess thyroid nodules. In the past, ultrasound-guided FNA was performed mainly by radiologists. However, many surgeons are increasingly being trained for this procedure now. In this study, we aimed to compare the adequacy and efficiency of ultrasound-guided FNA performed by newly trained head and neck surgeons with experienced radiologists in a single institution. We also assessed the malignancy rates in nondiagnostic nodules and the differences between benign and malignant nodules.

Methods

This is a retrospective study. The data from patients who underwent ultrasound-guided FNA performed by surgeons or radiologists in two consecutive years were collected. Medical records, cytology results, and surgical pathology results were analyzed.

Results

During the study period, a total of 2,405 ultrasound-guided FNAs were performed on 2,163 patients. The head and neck surgeons and radiologists performed 1,132 and 1,273 ultrasound-guided FNA procedures, respectively. The nondiagnostic rate was 14.49% for surgeons and 15.40% for radiologists (P=0.533). There were no differences in patient age, gender, nodule size, and other sonographic characteristics between the groups of patients who were treated by radiologists versus surgeons. The median waiting time from biopsy appointment to performing ultrasound-guided FNA was 0 days for head and neck surgeons, and 6 days for radiologists (P<0.001). Of the 40 patients who had a repeat FNA or surgery, 19 (47.50%) had a malignancy. Preoperative information about age, gender, operator, and characteristics of nodules did not predict the outcome of nodules with Bethesda category I.

Conclusions

The adequacy of ultrasound-guided FNAs performed by head and neck surgeons is similar to that of skilled radiologists, while surgeons are more efficient than radiologists. Nondiagnostic FNA reports should not be considered benign, and repeat FNA or selective surgical treatment is recommended.

The Bethesda System for Reporting Thyroid Cytopathology: A Cytohistological Study

Introduction

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) is a significant step to standardize the reporting of thyroid fine needle aspiration (FNA). It has high predictive value, reproducibility, and improved clinical significance.

Aim

The study was aimed to evaluate the diagnostic utility and reproducibility of "TBSRTC" at our institute. Methods and Material. The study included 646 thyroid FNAs which were reviewed by three pathologists and classified according to TBSRTC. Cytohistological correlation was done for 100 cases with surgical follow-up and the sensitivity, specificity, positive predictive value, negative predictive value, diagnostic accuracy, and risk of malignancy (ROM) were calculated. The interobserver variation among three pathologists was also assessed.

Results

The distribution of cases in various TBSRTC categories is as follows: I-nondiagnostic 13.8%, II-benign 75.9%, III-atypia of undetermined significance (AUS)/follicular lesion of undetermined significance (FLUS) 1.2%, IV-follicular neoplasm (FN)/suspicious for follicular neoplasm (SFN) 3.7%, V-suspicious for malignancy (SM) 2.6%, and VI-malignant 2.8%. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy are 72.4%, 94.3%, 84%, 89.2%, and 87.9%, respectively. The ROM of various TBSRTC categories were II-8.5%; III-66.7%; IV-63.6%; and V and VI-100%. Cohen's Weighted Kappa score was 0.99 which indicates almost perfect agreement among the three pathologists.

Conclusions

Our study substantiates greater reproducibility among pathologists using TBSRTC to arrive at a precise diagnosis with an added advantage of predicting the risk of malignancy which enables the clinician to plan for follow-up or surgery and also the extent of surgery.

McGill Thyroid Nodule Score in Differentiating Thyroid Nodules in Total Thyroidectomy Cases of Indeterminate Nodules

Fine-needle aspiration biopsy (FNAB) is the first-line modality in the evaluation of thyroid nodules. However, the results of indeterminate pathology place the thyroid surgeon in difficult management situations. This study evaluates McGill Thyroid Nodule Score (MTNS) to identify thyroid nodules that harbor malignancy in cases of indeterminate FNABs and to guide surgeon about the need and extent of surgery. We conducted a retrospective chart review of 344 patients who underwent total thyroidectomy between January 2013 and January 2018. Patients with FNAB of indeterminate nodules (Bethesda types III, IV, and V) and calculated MTNS were included in the study. Postoperative histopathology was divided into benign and malignant groups. The median and the mean MTNS, the malignancy rate, and the standard deviations were calculated for each subgroup. Of the 344 patient charts reviewed, 106 (30.8%) had an indeterminate FNA biopsy. Eighty-one (76.4%) patients were females and 25 (23.6%) were males. Final pathology revealed malignancy in 69 patients (65.1%). The mean MTNS of patients with malignant pathology (12.81  ± 3.55) was higher than the mean in the benign group (8.32  ± 2.32). 82.4% of thyroid nodules with median MTNS of less than 8 had a benign pathology, and 91.4% of thyroid nodules with median MTNS equal or more than 11 had a malignant pathology (p = 0.002). The rate of malignancy in our series of indeterminate FNABs was 65.1%. The MTNS can be of value to thyroid surgeons in preoperative decision-making when dealing with an indeterminate thyroid nodule.

Strain Elastography as a Valuable Diagnosis Tool in Intermediate Cytology (Bethesda III) Thyroid Nodules

Fine needle aspiration (FNA) is considered the gold standard in the diagnostic of thyroid nodules. Using the recommended BETHESDA reporting system, up to 20% of results are classified as intermediate cytology. As there is no consensus whether ultrasound evaluation, lobectomy or surgery is the best treatment option, intermediate cytology results are considered a grey zone of the FNA. The main aim of our study was to evaluate the performance of combined advanced ultrasound techniques in the process of diagnosis and evaluation of the intermediate cytology cases after FNA. We evaluated 54 consecutive cases with intermediate cytology on FNA, using conventional B-mode ultrasound (2B), and strain elastography, using a linear multifrequency 6-13 MHz linear probe (Hitachi Prerius Machine, Hitachi Inc, Japan). All nodules were classified with our Thyroid Imaging Report and Data System (TI-RADS) proposed model, considering: vertical appearance, with antero-posterior diameter bigger than the transvers diameter, the so called taller than wide shape, irregular borders, intranodular inhomogeneity, marked hypoecogenicity, micro calcifications, the presence of suspect lymph nodes, and increased stiffness as suspicious for malignancy. The classification outcomes were compared with the pathology results, considered the gold standard diagnosis. The prevalence of cancer was 28.8%, with 13/45 cases having a clear diagnostic of cancer. Six cases were diagnosed with borderline follicular neoplasia, a category with unclear evolution, also considered as malignant in the analysis of the imaging results. In total, 16/19 cancer cases had increased stiffness on elastography. The cancer prevalence increased with TI-RADS category, being 25% in TI-RADS 4b category and 92.8% in TI-RADS 5 category. The AUROC (Area Under Receiver Operating Curve) of elastography alone, in differentiation of malignant thyroid nodules was 74.9%; the combination of elastographic and conventional ultrasound characteristics generated an even better AUROC, of 84.5%. The combined conventional ultrasound and elastography identified thyroid cancer in cases with intermediate cytology with a sensitivity of 89.5% with a specificity of 50%. High risk thyroid nodules, identified by combined high risk conventional ultrasound characteristics and increased stiffness, on strain elastography, are highly predictive for malignancy, in the intermediate cytology cases.

Thyroid Nodules Cytopathology Applying the Bethesda System with Histopathological Correlation

Background

Fine-needle aspiration cytology remains a valuable screening tool for preoperative management of thyroid nodules. However, the rates of false-negative and false-positive diagnosis remain a challenge for pathologists.

Objectives

To assess the value of thyroid fine-needle aspiration as a screening tool and its accuracy of diagnoses relative to final histological diagnoses.

Patients and Methods

A chart review was conducted of all adult patients who underwent fine-needle aspiration of thyroid nodule(s) and were subjected to thyroid surgery at King Abdulaziz Medical City, Jeddah, Saudi Arabia, between January 2007 and June 2014. The fine-needle aspiration results were correlated with final histopathology results.

Results

Of the 408 aspirates from 373 patients, the Bethesda System for Reporting Thyroid Cytology (BSRTC) diagnostic categories were as follows: nondiagnostic in 26 aspirates (6.4%); benign in 128 (31.4%); atypia/follicular lesion of undetermined significance in 52 (12.7%); follicular neoplasm/suspicion for a follicular neoplasm in 83 (20.3%); suspicious for malignancy in 23 (5.6%) and malignant in 96 (23.5%). The comparative histopathological diagnoses were benign in 192 (47.1%) and malignant in 216 (52.9%) aspirates. The calculated risk of malignancy in the fine-needle aspiration categories was 34.6% in diagnostic category (DC) I, 15.6% in DC II, 50% in DC III, 52% in DC IV, 95.7% in DC V and 100% in DC VI. The sensitivity of fine-needle aspiration with BSRTC was 88.9%, specificity was 75.6%, positive predictive value was 79.7%, negative predictive value was 84.4% and accuracy was 81.5%.

Conclusion

The results of this retrospective study demonstrated higher risks of malignancy in DC I, DC II, DC III and DC IV than that of the original BSRTC definition, along with a higher specificity and positive predictive value for cancer diagnosis, and a lower sensitivity and negative predictive value.

Bethesda Classification and Cytohistological Correlation of Thyroid Nodules in a Brazilian Thyroid Disease Center

BACKGROUND

The Bethesda System has been used to classify thyroid cytology in 6 categories besides presenting malignancy rates and respective approaches. Reference centers have validated its use by comparing its proposed malignancy rates with those in in their populations. However, to the best of our knowledge, there has been no corresponding study in Brazil.

OBJECTIVES

To evaluate the performance of the Bethesda classification in a Brazilian thyroid reference center and correlate the results with cytohistological reports in patients referred to surgery.

METHODS

Data records from 980 fine-needle aspiration (FNA) results were retrospectively analyzed, and, in patients who underwent surgery, the results were correlated with the cytohistological findings.

RESULTS

980 FNAs and 585 patients were evaluated. The incidence of each cytological category was: 11% nondiagnostic (ND), 59.6% benign, 7.1% (atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS), 8.5% follicular neoplasm or suspicious for follicular neoplasm (FN/SFN), 5.1% suspicious for malignancy (SM), and 8.3% malignant. The surgery rate was 41.8% (245/585). The malignancy rate in each category was: 6% benign, 12% AUS/FLUS, 20.8% FN/SFN, 72.5% SM, and 97.3% malignant. For ND nodules, the malignancy rate was 25.7% (66.6% multifocal and papillary microcarcinomas), a higher rate than in the literature. In this category, surgery was performed in multinodular goiters presenting with another nodule > 3.0 cm and/or with an FN/SFN, SM, or malignant cytological result.

CONCLUSION

The Bethesda System can be applied to the Brazilian population, since the frequency and malignancy rates of each category were similar to those described by its classification. It is noteworthy that a higher risk of malignancy was observed in the ND cytological category.

Thyroid Fine-Needle Aspiration Cytology Practice in Korea

We reviewed the current status of thyroid fine-needle aspiration cytology (FNAC) in Korea. Thyroid aspiration biopsy was first introduced in Korea in 1977. Currently, radiologists aspirate the thyroid nodule under the guidance of ultrasonography, and cytologic interpretation is only legally approved when a cytopathologist makes the diagnosis. In 2008, eight thyroid-related societies came together to form the Korean Thyroid Association. The Korean Society for Cytopathology and the endocrine pathology study group of the Korean Society for Pathologists have been updating the cytologic diagnostic guidelines. The Bethesda System for Reporting Thyroid Cytopathology was first introduced in 2009, and has been used by up to 94% of institutions by 2016. The average diagnosis rates are as follows for each category: I (12.4%), II (57.9%), III (10.4%), IV (2.9%), V (3.7%), and VI (12.7%). The malignancy rates in surgical cases are as follows for each category: I (28.7%), II (27.8%), III (50.6%), IV (52.3%), V (90.7%), and VI (100.0%). Liquid-based cytology has been used since 2010, and it was utilized by 68% of institutions in 2016. The categorization of thyroid lesions into "atypia of undetermined significance" or "follicular lesion of undetermined significance" is necessary to draw consensus in our society. Immunocytochemistry for galectin-3 and BRAF is used. Additionally, a molecular test for BRAF in thyroid FNACs is actively used. Core biopsies were performed in only 44% of institutions. Even the institutions that perform core biopsies only perform them for less than 3% of all FNACs. However, only 5% of institutions performed core biopsies up to three times more than FNAC.

Proposal for a novel management of indeterminate thyroid nodules on the basis of cytopathological subclasses

Indeterminate thyroid nodules include heterogeneous lesions that could benefit from a differential management. Our aim is to better define the management of the Bethesda System for Reporting Thyroid Cytopathology class III and IV nodules, by identifying cytological subcategories among Bethesda System for Reporting Thyroid Cytopathology class III associated with different clinical risk, by means of ultrasound, repeated FNAB, and BRAFV600E molecular analysis. We also evaluated the outcome of nodules not operated, over a 5-year follow-up. Out of 460 nodules (269 Bethesda System for Reporting Thyroid Cytopathology class III and 191 Bethesda System for Reporting Thyroid Cytopathology class IV), 344 were operated on surgical group and 116 followed-up conservatively (follow-up group). Bethesda System for Reporting Thyroid Cytopathology class III was divided into four subcategories on the basis of cytomorphological features (III-1, III-2, III-3, III-4). Clinical risk was defined on the basis of histological, cytological, and ultrasound data. Malignancy was higher in Bethesda System for Reporting Thyroid Cytopathology class III vs. Bethesda System for Reporting Thyroid Cytopathology class IV (34.4 vs. 26.2 %; p < 0.01). Papillary thyroid carcinoma was the most frequent cancer in each Bethesda System for Reporting Thyroid Cytopathology class (35 %). BRAFV600E diagnostic accuracy was 87 %. Repeated FNAB reclassified as benign nearly 40 % of nodules, selecting patients where surgery could be spared. Significant nodule growth occurred in 13.7 % of nodules, belonging mostly to Bethesda System for Reporting Thyroid Cytopathology class III-2 and Bethesda System for Reporting Thyroid Cytopathology class IV. Overall clinical risk was higher in Bethesda System for Reporting Thyroid Cytopathology III-1, III-4, and IV classes. We propose a differential management of Bethesda System for Reporting Thyroid Cytopathology III and IV classes and related subcategories: surgery may be indicated in Bethesda System for Reporting Thyroid Cytopathology class III-1, III-4, and IV; a conservative follow-up avoiding repeated FNAB may be appropriated in class III-3, while repeated FNAB may be useful in class III-2.

The Use of the Bethesda System for Reporting Thyroid Cytopathology in Korea: A Nationwide Multicenter Survey by the Korean Society of Endocrine Pathologists

Background

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) has standardized the reporting of thyroid cytology specimens. The objective of the current study was to evaluate the nationwide usage of TBSRTC and assess the malignancy rates in each category of TBSRTC in Korea.

Methods

Questionnaire surveys were used for data collection on the fine needle aspiration (FNA) of thyroid nodules at 74 institutes in 2012. The incidences and follow-up malignancy rates of each category diagnosed from January to December, 2011, in each institute were also collected and analyzed.

Results

Sixty out of 74 institutes answering the surveys reported the results of thyroid FNA in accordance with TBSRTC. The average malignancy rates for resected cases in 15 institutes were as follows: nondiagnostic, 45.6%; benign, 16.5%; atypical of undetermined significance, 68.8%; suspicious for follicular neoplasm (SFN), 30.2%; suspicious for malignancy, 97.5%; malignancy, 99.7%.

Conclusions

More than 80% of Korean institutes were using TBSRTC as of 2012. All malignancy rates other than the SFN and malignancy categories were higher than those reported by other countries. Therefore, the guidelines for treating patients with thyroid nodules in Korea should be revisited based on the malignancy rates reported in this study.

Bethesda System for Reporting Thyroid Cytopathology: A three-year study at a tertiary care referral center in Saudi Arabia

AIM

To stratify the malignancy risks in thyroid nodules in a tertiary care referral center using the Bethesda system.

METHODS

From January, 2012 to December, 2014, a retrospective analysis was performed among 1188 patients (15-90 years) who had 1433 thyroid nodules and fine-needle aspiration at Prince Sultan Military Medical City, Saudi Arabia. All thyroid cyto-pathological slides and ultra sound reports were reviewed and classified according to the Bethesda System for Reporting Thyroid Cytopathology. Age, gender, cytological features and histological types of the thyroid cancer were collected from patients’ medical chart and cytopathology reports.

RESULTS

There were 124 total cases of malignancy on resection, giving an overall surgical yield malignancy of 33.6%. Majority of the thyroid cancer nodules (n = 57, 46%) in Bethesda VI category followed by Bethesda IV (n = 25, 20.2%). Almost 40% of the cancer nodules in 31-45 age group in both sex. Papillary thyroid carcinoma (PTC) was the most common form of thyroid cancer among the study population (111, 89.6%) followed by 8.9% of follicular thyroid carcinoma (FTC), 0.8% of medullary carcinoma and 0.8% of anaplastic carcinoma. Among the Bethesda IV category 68% thyroid nodules were PTC and 32% FTC.

CONCLUSION

The malignancy values reported in our research were constant and comparable with the results of other published data with respect to the risk of malignancy. Patients with follicular neoplasm/suspicious for follicular neoplasm and suspicious of malignancy categories, total thyroidectomy is indicted because of the substantial risk of malignancy.

A study of malignancy rates in different diagnostic categories of the Bethesda system for reporting thyroid cytopathology: An institutional experience

Background

The Bethesda system for reporting thyroid cytopathology (TBSRTC) was introduced to standardize the communication of fine-needle aspiration cytology (FNAC) interpretation between clinicians and pathologists. This study was undertaken to evaluate the diagnostic utility of TBSRTC for reporting thyroid FNACs and rate of malignancy in each diagnostic category of TBSRTC.

Methods

A total of 603 thyroid FNAC results were retrieved retrospectively between July 2012 and January 2015 and reclassified according to TBSRTC. Of these, 392 cases had a histopathological follow-up. The FNACs results were compared to the histopathological diagnoses and the malignancy rates of each diagnostic categories of TBSRTC were calculated.

Results

Of the 603 FNACs, nondiagnostic were 16 (2.7%), benign were 393 (65.2%), atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) were 60 (10%), follicular neoplasm/suspicious for a follicular neoplasm (FN/SFN) were 64 (10.6%), suspicious for malignancy (SM) were 32 (5.3%), and malignant were 38 (6.3%). In 392 cases, there was follow-up histopathology. The malignancy rate for nondiagnostic, benign, AUS/FLUS, FN/SFN, SM, and malignant categories were 0%, 0.8%, 24.4%, 28.9%, 70.8%, and 100%, respectively.

Conclusion

Our study validated the efficacy of TBSRTC. In conclusion, the malignancy rate of AUS/FLUS in this study was higher than the risk mentioned in TBSRTC and other published studies. Hence, AUS/FLUS category patients in our setup warrant further workup including ultrasound and/or thyroid scan in addition to immediate repeat FNAC.

Use of supravital toluidine blue staining to improve the efficiency of fine-needle aspiration cytology reporting in comparison to papanicolaou stain

OBJECTIVE

To see the efficiency, adequacy and accuracy of toluidine blue stained smears of FNAC of Breast thyroid and salivary glands swelling with comparison to conventional stained FNAC smears with Papanicolaou.

METHODS

A total of 114 aspirates from various sites were included in the study. The smears were stained with toluidine blue and conventional Papanicolaou stain and the cytomorphology of both the smears were compared. The values were tabulated and statistical tests of significance was applied.

RESULTS

Of the 114 aspirates included in our study the diagnostic accuracy by using papanicolaou was 78%, while it was upto 100% with supravital toluidine blue stained smears. The percentage of inadequacy was reduced to just 25%. The observations were statistically significant. Breast 37/48 (77%) and Salivary glands 11/48 (23%) respectively. The most commonly used categorization of a five-tier system was used for reporting of breast cytology, with categories ranging from insufficient materials (C1), benign (C2), atypical (C3), suspicious of malignancy (C4), or (C5) frankly malignant. Most of breast lesions were benign 25 (67.56%). There were only 9 (24.32%) malignant cases followed by 2 cases of C-4 and one case of C-3. Benign thyroid lesion were more frequent comprising of 51 (72.27%) cases. One case (1.5%) of papillary carcinoma was found while 13 case were follicular lesions. There were 4 (36.4%) cases of pleomorphic adenoma and 3 (27.3) cases of non-specific sialadenitis. There was one case (9%) of each lesion for mucoepidermoid carcinoma, adenoidcytic carcinoma and benign cyst.

CONCLUSION

Toluidine blue stained study of FNAC improves the diagnostic accuracy by minimizing the smearing and drying artifact, loss of cell sample during fixation and staining which influences the diagnostic accuracy.

Value of TIRADS, BSRTC and FNA-BRAF V600E mutation analysis in differentiating high-risk thyroid nodules

The thyroid imaging reporting and data system (TIRADS) and Bethesda system for reporting thyroid cytopathology (BSRTC) have been used for interpretation of ultrasound and fine-needle aspiration cytology (FNAC) results of thyroid nodules. BRAF(V600E) mutation analysis is a molecular tool in diagnosing thyroid carcinoma. Our objective was to compare the diagnostic value of these methods in differentiating high-risk thyroid nodules. Total 220 patients with high-risk thyroid nodules were recruited in this prospective study. They all underwent ultrasound, FNAC and BRAF(V600E) mutation analysis. The sensitivity and specificity of TIRADS were 73.1% and 88.4%. BSRTC had higher specificity (97.7%) and similar sensitivity (77.6%) compared with TIRADS. The sensitivity and specificity of BRAF(V600E) mutation (85.1%, 100%) were the highest. The combination of BSRTC and BRAF(V600E) mutation analysis significantly increased the efficiency, with 97.8% sensitivity, 97.7% specificity. In patients with BSRTC I-III, the mutation rate of BRAF(V600E) was 64.5% in nodules with TIRADS 4B compared with 8.4% in nodules with TIRADS 3 or 4A (P < 0.001). Our study indicated that combination of BSRTC and BRAF(V600E) mutation analysis bears a great value in differentiating high-risk thyroid nodules. The TIRADS is useful in selecting high-risk patients for FNAB and patients with BSRTC I-III for BRAF(V600E) mutation analysis.

Diagnostic accuracy of Bethesda system for reporting thyroid cytopathology: an institutional perspective

Introduction

Thyroid swelling is common problem among South Asian women. Although benign nodules far outnumber cancerous lesions, the risk of malignancy needs to be evaluated preoperatively for which fine needle aspiration cytology (FNAC) is widely used. Bethesda system for reporting thyroid cytopathology (BSRTC) was introduced to streamline the reporting of thyroid aspirates. We aimed to evaluate the disease spectrum of thyroid cytopathology and correlation of BSRTC with final histopathology in our setup.

Methods

The study was conducted at Histopathology department of Liaquat National Hospital, Karachi, involving 528 patients with thyroid swelling who underwent FNAC. Out of these 528 cases, 61 patients subsequently underwent surgical excision. Results of final histopathology were correlated with cytologic diagnosis.

Results

Mean age of the patients included in the study was 39.7 ± 13(14–84) and male to female ratio was 1:3.6. Out of total 528 cases, 403 cases were diagnosed as benign (Bethesda 2) and 67 were Bethesda 3 (follicular lesion of undetermined significance, FLUS) while 22 cases were categorized as either malignant or suspicious for malignancy (Bethesda 6 and 5). Histopathologic correlation was done in 61 cases. For Bethesda 5 and 6 categories, 100% concordance was found, however for Bethesda 2 category, 5 out of 45 cases were found to have malignant diagnosis on final histopathology. The incidence of malignancy in Bethesda categories 2 through 4 were 11.1%, 33.4%, 25%, 100% and 100% respectively. Overall accuracy of FNA cytology was 80.3% with 64.3% sensitivity and 85.1% specificity.

Conclusion

Our study validated the accuracy of BSRTC in our setup. Therefore we recommend routine use of BSRTC for reporting thyroid cytopathology for initial workup of patients with thyroid nodule. However, risk of malignancy was found to be significantly high in Bethesda 3 category to warrant further workup including ultrasound/thyroid scan in addition to repeat FNAC.