The National Cancer Institute Thyroid fine needle aspiration state of the science conference: a summation

Comparison of Cytological Adequacy between 23- and 25-Gauge in Ultrasound-Guided Fine-Needle Aspiration of Thyroid Nodules: A Single-Center Prospective Study

INTRODUCTION

Approximately 15% of fine-needle aspiration (FNA) of thyroid nodules are considered nondiagnostic. Several factors are potentially involved, including clinical and nodule features but also the gauge (G) of the needle used. However, few studies have compared the cytological adequacy obtained with different gauge needles and the data are controversial. We aimed to evaluate cytological adequacy results using 23- or 25-G needles.

METHODS

This study is an observational and prospective study of thyroid nodules submitted to ultrasound-guided FNA. The procedure was performed randomly using 23- or 25-G needles. The samples were reported by different cytopathologists who were blinded to the information of the gauge of the needle used. Statistical analysis was performed to compare cytological adequacy of FNA between the two groups.

RESULTS

A total of 177 thyroid nodules were included - 98 (55.4%) using 23-G and 79 (44.6%) using 25-G needles. The 23-G group presented a higher rate of cytological adequacy (69.4% [68/98] vs. 46.8% [37/79], p = 0.002). No differences were found between the two groups regarding patient or nodule characteristics. On logistic regression, 23-G needles correlated with better cytological adequacy (unadjusted OR 2.57 [95% CI: 1.39-4.77]), even after adjusting for nodule dimension, location, and type of cytology (slides +/- additional liquid-based cytology) (adjusted OR 2.44 [95% CI: 1.23-4.84]).

CONCLUSION

The gauge of the needle used was found to be an independent predictor of cytological adequacy, with 23-G needles providing more adequate samples. Further investigation is needed to confirm our results in order to stablish the optimal diagnosis technique.

Performance of ACR TI-RADS and the Bethesda System in Predicting Risk of Malignancy in Thyroid Nodules at a Large Children's Hospital and a Comprehensive Review of the Pediatric Literature

While thyroid nodules are less common in children than in adults, they are more frequently malignant. However, pediatric data are scarce regarding the performance characteristics of imaging and cytopathology classification systems validated to predict the risk of malignancy (ROM) in adults and select those patients who require fine-needle aspiration (FNA) and possibly surgical resection. We retrospectively reviewed the electronic medical records of all patients 18 years of age or younger who underwent thyroid FNA at our institution from 1 July 2015 to 31 May 2022. Based on surgical follow-up from 74 of the 208 FNA cases, we determined the ROM for the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) ultrasound risk stratification system and The Bethesda System for Reporting Thyroid Cytopathology and added our results to those of pediatric cohorts from other institutions already published in the literature. We found the following ROMs for 1458 cases using ACR TI-RADS (TR): TR1. Benign: 2.2%, TR2. Not Suspicious: 9.3%, TR3. Mildly Suspicious: 16.6%, TR4. Moderately Suspicious: 27.0%, and TR5. Highly Suspicious 76.5%; and for 5911 cases using the Bethesda system: Bethesda I. Unsatisfactory: 16.8%, Bethesda II. Benign: 7.2%, Bethesda III: Atypia of Undetermined Significance: 29.6%, Bethesda IV. Follicular Neoplasm: 42.3%, Bethesda V. Suspicious for Malignancy: 90.8%, and Bethesda VI. Malignant: 98.8%. We conclude that ACR TI-RADS levels imply higher ROMs for the pediatric population than the corresponding suggested ROMs for adults, and, in order to avoid missing malignancies, we should consider modifying or altogether abandoning size cutoffs for recommending FNA in children and adolescents whose thyroid glands are smaller than those of adults. The Bethesda categories also imply higher ROMs for pediatric patients compared to adults.

Adverse events unlikely after fine-needle aspiration biopsies of thyroid nodules in patients on low-dose aspirin: a prospective controlled systematic single center analysis

AIM

Our aim was to test the assertion that in terms of rate or severity level, adverse events (AEs) after fine-needle aspiration biopsies (FNABs) of thyroid nodules are unfazed by daily low-dose (100 mg) aspirin (acetylsalicylic acid, ASA) intake.

METHODS

We selected 268 patients for study, grouped as ASA-treated (P_ASA, n=78) or control (P_Ctrl, n=190) subjects. Controls received no antithrombotic medication. AE rates and severities were then analyzed based on patient- and nodule-related factors. We also compared group rates of non-diagnostic cytology results.

RESULTS

AEs arising after FNABs (P_ASA, 5%; P_Ctrl, 8%) did not differ significantly by group in rate (p=0.4873) or severity level (p=0.3399). All were classifiable as minor incidents, none warranting any intervention.

CONCLUSIONS

The data from the present study suggest, AEs after FNABs of thyroid nodules seldom occur and qualify as minor incidents. Such procedures may be safely conducted in patients taking daily low-dose ASA. There is no evidence to support preemptive therapeutic withdrawal.

Molecular testing in thyroid cancer diagnosis and management

Molecular diagnostic testing has had a profound impact on the diagnosis and management of thyroid nodules and thyroid cancer. Based on the tremendous expansion of knowledge of the genomic landscape of thyroid cancer over the past few decades, tests have been developed, analyzed, modified, and implemented into clinical practice. Genomic testing of thyroid nodules to improve preoperative diagnosis has become an important component supporting decision-making in clinical care, reducing the need for diagnostic surgeries and improving accuracy of cancer risk assessment. In addition, a role for molecular testing of established thyroid cancers to assist in selection of therapeutic options for patients with advanced and/or progressive disease has been established. Research is ongoing to determine if molecular results should affect management of less aggressive forms of thyroid cancer earlier in clinical management. This review will outline the various commercial platforms for molecular diagnostics for nodules emphasizing their performance parameters and indications for use, as well as discuss the use of genomic analysis for progressive thyroid cancer and highlight opportunities for further research.

Cost-effectiveness analysis of molecular testing for cytologically indeterminate thyroid nodules

BACKGROUND

Thyroid nodules affect up to 65% of the population. Although fine needle aspirate (FNA) cytology is the gold standard for diagnosis, 15-30% of results are indeterminate. Molecular testing may aid in the diagnosis of nodules and potentially reduce unnecessary surgery. However, these tests are associated with significant costs. The objective of this study was to evaluate the cost-effectiveness of Afirma, a commercially available molecular test, in cytologically indeterminate thyroid nodules.

METHODS

The base case was a solitary thyroid nodule with no additional high-risk features and an indeterminate FNA. Decision tree analysis was performed from the single payer perspective with a 1-year time horizon. Costing data were collected through micro-costing methodology. A probabilistic sensitivity analysis was performed. The primary outcome was the incremental cost effectiveness ratio (ICER) of cost per thyroid surgery avoided.

RESULTS

Over 1 year, mean cost estimates were $8176.28 with 0.58 effectiveness for the molecular testing strategy and $6016.83 with 0.07 effectiveness for current standard management. The ICER was $4234.22 per surgery avoided. At a willingness-to-pay (WTP) threshold of $5000 per surgery avoided, molecular testing is cost-effective with 63% certainty.

CONCLUSION

This cost-effectiveness analysis suggests utilizing Afirma for indeterminate solitary thyroid nodules is a cost-effective strategy for avoiding unnecessary thyroid surgery. With a $5000 WTP threshold, molecular testing has a 63% chance of being the more cost-effective strategy. The cost effectiveness varies based on the cost of the molecular test and the value of Afirma for patients with indeterminate thyroid nodules depends on the WTP threshold to avoid unnecessary thyroid surgery.

Core Needle Biopsy in Suspicious Malignant Thyroid Nodules with Repeated Nondiagnostic Fine Needle Aspiration

Key message

The clinician could have CNB in mind for thyroid nodules when FNA results were nondiagnostic. Our study would suggest CNB a safe and efficient method for investigating thyroid nodules.

Abstract

Usefulness of preoperative tissue sampling and pathology diagnoses in thyroid tumors were accepted worldwide. We investigate the role of Core needle biopsy (CNB) in the thyroid nodules lesions when FNA results are nondiagnostic. We conducted a cross-sectional study to evaluate twenty-six CNBs results of suspicious malignant thyroid nodules with nondiagnostic repeated fine needle aspiration. 25 from 26 CNBs were diagnostic. Twenty-one needle biopsy reports were papillary thyroid carcinoma, three CNB samples diagnosed medullary thyroid carcinoma and one of them had anaplastic results. All diagnostic needle biopsies results were compatible with final pathology. Our study would suggest CNB a safe and efficient method for investigating thyroid nodules while repeated FNA yielded nondiagnostic results.

Machine Learning-Assisted Diagnostic System for Indeterminate Thyroid Nodules

To develop an ultrasound-based machine learning classifier to diagnose benignity within indeterminate thyroid nodules (ITNs) by fine-needle aspiration, 180 patients with 194 ITNs (Bethesda classes III, IV and V) undergoing surgery over a 5-y study period were analyzed. The data set was randomly divided into training and testing data sets with 155 and 39 ITNs, respectively. All nodules were evaluated by ultrasound using the American College of Radiology Thyroid Imaging Reporting and Data System by manually scoring composition, echogenicity, shape, margin and echogenic foci. Nodule size, participant age and patient sex were recorded. A support vector machine (SVM) model with a cost-sensitive approach was developed using the aforementioned eight parameters with surgical histopathology as the reference standard. Surgical pathology determined 90 (46.4%) ITNs were malignant and 104 (53.6%) were benign. The SVM model classified 14 nodules as benign in the testing data set, of which 13 were correct (sensitivity = 93.8%, specificity = 56.5%). Considering malignancy prevalence by Bethesda group, the negative predictive values of this model for Bethesda III and IV categories were 93.9% and 93. 8%, respectively. The high negative predictive value of the SVM ultrasound-based model suggests a pathway by which surgical excision of Bethesda III and IV ITNs classified as benign may be avoided.

Features and diagnostic accuracy of fine needle aspiration cytology of thyroid nodules: retrospective study from Oman

BACKGROUND

Fine needle aspiration cytology (FNAC) of the thyroid has been a reliable and cost-effective method for diagnosing thyroid disorders. Since FNAC results are usually operator dependent, there is a compelling need to explore FNAC accuracy among Omanis.

OBJECTIVE

Describe cytological features of FNAC and assess FNAC accuracy compared to the postsurgical histopathology report.

DESIGN

Retrospective diagnostic accuracy study SETTING: Tertiary care center.

PATIENTS AND METHODS

Our study included adult Omani adult patients with thyroid nodules who underwent FNAC from 2014 to 2017 and had final pathology results for patients who underwent thyroid surgery. The results were classified according to the UK Royal college of Pathologists 'Thy' categories. Accuracy of FNAC was calculated by determining false and true positive and negative results based on histopathology findings.

MAIN OUTCOME MEASURES

FNAC accuracy (sensitivity and specificity) compared to the postsurgical histopathology.

SAMPLE SIZE

867 patients with 1359 ultrasound guided FNACs of thyroid nodule; 137 underwent surgery.

RESULTS

The mean age of the 867 patients was 43.7 (13.3) years, with a median of 42 years, and 87.8% were females. Out of 1359 FNACs, 1001 (73.7%) were benign (Thy2), 119 (8.8%) were atypia of undetermined significance or follicular lesion of undetermined significance (Thy3a), 31 (2.3%) were follicular neoplasm or suspicious for a follicular neoplasm (Thy3f), 52 (3.8%) were suspicious for malignancy (Thy4), 55 (4%) were malignant (Thy5), 101 (7.4%) as Unsatisfactory (Thy1). Only 137 patients underwent thyroid surgery, and the FNAC reports were compared with their final histopathology reports. The sensitivity, specificity and total accuracy of FNAC were 80.2%, 98.9% and 89.9%, respectively. The positive and negative predictive values of FNAC were 98.6% and 84.3%, respectively.

CONCLUSION

Our study findings confirmed that FNAC of the thyroid is a sensitive, specific, and accurate initial tool for the diagnosis of thyroid lesions. Most of the FNACs were benign with a very low malignancy rate. Due to the minimal chance of false negative results and the slow-growing nature of thyroid malignancy, it is important that patients with benign FNAC should have periodic clinical and radiological follow-up.

LIMITATIONS

Retrospective design and single-center study, and thyroid nodule size unavailable.

CONFLICT OF INTEREST

None.

Diagnosis of thyroid nodules

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

Epidemiological, Clinical, Ultrasonographic and Cytological Characteristics of Thyroid Nodules in an Afro-Caribbean Population: A Series of 420 Patients

Simple Summary

This study describes the epidemiological, clinical and ultrasound characteristics of malignancy in thyroid nodules and evaluates the value of cytology in the diagnosis of malignancy in an Afro-Caribbean population. Our results revealed that none of the standard ultrasound criteria of malignancy were significantly predictive of cancer, but hypoechogenicity and central vascularity were frequently found in malignant nodules. These results could increase awareness and guide practitioners in their diagnostic approach and management of thyroid nodules in Afro-Caribbean populations. Bethesda system-based cytology revealed low sensitivity in analyzing the risk of malignancy in this population. The high prevalence of papillary microcarcinomas may explain the inconclusive ultrasound and cytological results.

Abstract

The incidence of thyroid cancer is increasing worldwide. The aim of this study is to describe the epidemiological, clinical and ultrasound characteristics of malignancy in thyroid nodules and to evaluate the predictive value of the Bethesda system for thyroid cytology in the diagnosis of malignancy in an Afro-Caribbean population. We conducted a retrospective study in Martinique involving 420 patients with a diagnosis of thyroid nodules between 2011 and 2014. Of the 192/420 (45.7%) patients operated on for thyroid nodules, 9% had thyroid cancer. All patients with thyroid cancer were obese women with a mean age of 50 years. The final histological examination revealed papillary microcarcinomas in 61% of cases and papillary carcinomas in 39% of cases. Thyroid cytology alone had a low sensitivity (22.2%) and positive predictive value (15.4%) for the diagnosis of malignancy, with a good specificity (91.1%) and negative predictive value (94.2%). None of the standard ultrasound criteria of malignancy were significantly predictive of cancer, but hypoechogenicity and central vascularity were frequently found in malignant nodules. These epidemiological, clinical and ultrasound results could increase awareness and guide practitioners in their diagnostic approach and management of thyroid nodules in an Afro-Caribbean population. Bethesda system-based cytology revealed lower sensitivity in analyzing the risk of malignancy in this population. The high prevalence of papillary microcarcinomas may explain the inconclusive ultrasound and cytological results.

Long-term Follow-up of Cytologically Indeterminate Thyroid Nodules Found Benign on Molecular Testing: A Validation Study

Objective

Molecular testing has revolutionized management of indeterminate thyroid nodules (Bethesda categories III and IV). Few studies have attempted to validate the negative predictive value of molecular tests. Using long-term observation as a surrogate for surgical resection, we sought to examine the false-negative rate of “benign” indeterminate thyroid nodules on molecular testing.

Study Design

Case series with retrospective data collection and chart review.

Setting

Large community-based practice with multiple satellite offices.

Methods

All patients with thyroid nodules that underwent ultrasound-guided fine-needle aspiration biopsy between 2013 and 2019 were evaluated through retrospective analysis. Cytologically indeterminate nodules reflexively underwent molecular testing to guide clinical management. Observation was recommended for lesions with benign molecular testing, and these nodules were followed clinically and by ultrasound.

Results

A total of 2011 nodules underwent fine-needle aspiration, of which 280 (14%) were indeterminate thyroid nodules. Of those 280 nodules, 100 (36%) were benign on molecular testing. Three samples were excluded from analysis due to patient deaths from unrelated causes. Surgical resection was recommended in 16 of the 97 nodules (17%), with the majority due to size and compressive symptoms. Histopathology was available in 14 nodules that underwent surgery, with 1 demonstrating minimally invasive follicular carcinoma.

Conclusion

While molecular testing is safe to use in guiding management of indeterminate thyroid nodules, consideration of individualized clinical factors and close long-term follow-up remains paramount.

Acute transient swelling of the thyroid following fine-needle aspiration: A case series

Acute transient swelling (ATS) of the thyroid is a rare complication following fine-needle aspiration (FNA) of thyroid nodules. We present 31 cases with 35 nodules encountered at our institute and reported in the literature, to provide further information. The incidence rate in our institute was 0.46%. Of these nodules, 74.3% (26/35) were solid, 65.7% (23/35) exhibited hypervascularity, and 77.2% (27/35) were benign or follicular neoplasms. Although most cases (87.1%, 27/31) occurred within 2 h after FNA, four patients experienced delayed ATS after 7 h to 2 days. Therefore, awareness of this complication, especially its delayed occurrence, should be raised.

A Bibliometric Analysis of 8271 Publications on Thyroid Nodules From 2000 to 2021

INTRODUCTION

Thyroid nodules (TNs) are a common clinical condition. The probability of thyroid nodules being malignant is 7-15%. However, in recent decades, a number of publications on TNs have not been well summarized and discussed. The aim of this study was to summarize and sort out medical publications on TNs over the past 2 decades using a bibliometric method.

MATERIALS AND METHODS

Medical publications from January 1^st, 2000, to November 1^st, 2021, were searched in the Web of Science Core Collection database using the Medical Subject Heading (MeSH) term "thyroid nodule". Full associated data were downloaded, and detailed information was extracted using the bibliometric analysis platform VOSviewer.

RESULTS

A total of 8271 publications related to TNs from the last 2 decades were found and included in this study. An increasing trend was presented in the annual number of publications. The United States, China and Italy contributed the most publications. Carcinoma, management, ultrasound, and fine-needle aspiration were the most popular subjects in the field of TNs. The topics of the studies could be stratified into four clusters. The first cluster was using ultrasound to evaluate the nodules, including the thyroid imaging reporting and data system (TI-RADS), elastography and benign features. The second cluster was the fine-needle aspiration method, including the Bethesda system, cytology and BRAF mutations. The third cluster was the management of nodules, including radiofrequency and thermal ablation, surgery, and consensus statements. The last cluster was carcinoma, which is correlated with all three clusters described above. The preoperative diagnosis of cytologically indeterminate nodules was particularly highlighted in the top 10 most cited publications in recent years.

CONCLUSION

How to diagnose thyroid nodules as malignant or benign, especially in cytologically indeterminate nodules, is still the most concerning topic in TN research. Although the fine-needle aspiration method and gene-expression classifiers show promising results, there is still a crucial need for translations from fundamental studies to clinical applications.

Comparative Study of ACR TI-RADS and ATA 2015 for Ultrasound Risk Stratification of Thyroid Nodules

OBJECTIVE

To study the adoption rate of the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) scoring system over a 3-year period in a community setting and compare its performance with that of the American Thyroid Association 2015 (ATA 2015) ultrasound risk scoring system.

STUDY DESIGN

Case series with prospective data collection and retrospective chart review.

SETTING

Large community-based practice with multiple satellite offices and a dedicated thyroid ultrasound clinic.

METHODS

All patients referred to the thyroid clinic between January 2018 and December 2020 for ultrasound-guided fine-needle biopsy were assigned an ATA 2015 risk score in a prospective manner immediately prior to biopsy. ACR TI-RADS scores were recorded through retrospective chart review of the radiologist report. Performance of the 2 systems was compared with cytology as the gold standard.

RESULTS

A total of 949 nodules underwent biopsy, of which 236 had available data for both scoring systems. There was a 33.8% increase in adoption of the ACR TI-RADS over the 3-year study period. The ATA 2015 guidelines yielded sensitivity and specificity of 81.6% and 54.5%, respectively, as opposed to 73.7% and 27.0% for the ACR TI-RADS.

CONCLUSION

In our community, there has been a gradual increase in adoption of the ACR TI-RADS, although the ATA 2015 risk scoring system has performed better.

Evaluation of the American College of Radiology Thyroid Imaging, Reporting and Data System (Thyroid imaging reporting) scoring in thyroid Bethesda category on atypia and follicular lesion of uncertain significance patients

OBJECTIVE

Treatment and follow-up are controversial in patients whose thyroid fine needle aspiration biopsy (FNAB) is reported as atypia of undetermined significance and follicular lesion of uncertain significance (AUS/FLUS). We aimed the efficacy of the American College of Radiology Thyroid Imaging, Reporting and Data System (ACR TI-RADS) in preventing unnecessary thyroidectomies in patients with FNA cytology results as AUS/FLUS.

METHODS

In Bolu Abant Izzet Baysal University General Surgery Clinic, case series between 2017 and 2020 were analyzed with thyroid operated. Grouping was made according to the result of postoperative pathology: those with benign results after postoperative pathology were classified as Group 1, and those with malignant results after postoperative pathology were classified as Group 2.

RESULTS

As a result, 66 patients were found to be AUS/FLUS. A total of 28.8% of AUS/FLUS patients have been determined with cancer. In the statistical analysis of the ACR TI-RADS score between the groups, the ACR TI-RADS score in Group 1 patients (3.36) (SD 0.87) was significantly lower than that in Group 2 patients (4.11) (SD 1.04) (p=0.003). The distribution of the ACR TI-RADS scores of the patients in Group 2 was TR2: 2 (15.4%) patients, TR3: 3 (25%) patients, TR4: 5 (16.1%), TR5: 9 (90%) patients, respectively.

CONCLUSION

The ACR TI-RADS score was statistically significant in predicting malignancy in AUS/FLUS patients whose follow-ups and treatments are controversial, and the ACR TI-RADS has a limited role in preventing unnecessary thyroidectomies in patients with AUS/FLUS.

Improving Malignancy Prediction in AUS/FLUS Pediatric Thyroid Nodules with the Aid of Ultrasound

INTRODUCTION

The standard workup of thyroid nodules concerning for malignancy includes fine-needle aspiration (FNA). In 2015, the American Thyroid Association (ATA) guidelines for the management of pediatric thyroid nodules recommended that all nodules with a Bethesda III cytology undergo surgical resection.

OBJECTIVES

To correlate a Bethesda III cytology with histologic and clinical outcomes to determine the relevance of the ATA recommendations, and to evaluate whether Thyroid Imaging Reporting and Data System (TI-RADS) scoring could identify Bethesda III nodules at a lower risk of malignancy.

METHODS

A retrospective chart review of patients who had undergone thyroid nodule FNA from 2008 to 2018 was performed. Malignancy rates were determined for each Bethesda category. The reference standard was histopathology or 2-year follow-up of imaging outcomes for nonoperative cases. Ultrasound exams of Bethesda III nodules were reviewed and TI-RADS scores assigned.

RESULTS

A total of 143 FNA samples from 128 patients were identified. The mean age was 14.9 years (range 7-22). Twenty-two (15%) of the FNA samples were Bethesda III; the malignancy rate was 38%. A TI-RADS score was assigned in 20 of the 22 Bethesda III nodules. ROC analysis found an optimal cut-off for malignancy prediction of ≥7 points (risk category TR5). The negative predictive value was 85.7% (95% CI 35.9-99.6) and the positive predictive value was 83.3% (95% CI 57.2-98.2).

CONCLUSION

Although, at baseline, thyroid nodules with a Bethesda III classification carry a moderate risk of malignancy in the pediatric population, TI-RADS scoring can identify nodules with a lower risk within this group. If validated by larger studies, this can inform decision making and reduce unneeded surgery.

Preoperative Molecular Testing of Thyroid Nodules: Current Concepts

Robust molecular testing is commercially available for adjuvant assessment of cytologically indeterminate thyroid nodules. Testing has been developed and optimized for fine needle aspiration biopsy collections of thyroid nodules typically under ultrasound evaluation. These assays use a combination of gene expression and/or DNA and RNA assessments for molecular alterations to stratify indeterminate thyroid nodules as benign with risk level similar to benign cytologic read or suspicious with increased risk of malignancy. Guidelines for when to consider adjuvant molecular testing will be discussed.

Evaluation of thyroid lesions by fine-needle aspiration cytology based on Bethesda system for reporting thyroid cytopathology classification among the population of South Bihar

Background:

Fine-needle aspiration (FNA) of the thyroid gland has proven to be an important and widely accepted, cost-effective, simple, safe, and accurate method triaging patients with thyroid nodules. Awareness and understanding of wide spectrum thyroid disorders are of great value because most lesions are treatable by medical or surgical management.

Aim:

The aim of this study is to determine the accuracy of FNA cytology (FNAC) in the diagnosis of thyroid lesion using the Bethesda system for reporting thyroid cytopathology nomenclature (BSRTC) and to correlate these with histopathological findings.

Materials and Methods:

FNA was performed in 238 patients from January 2014 to October 2015 at a Tertiary Teaching Hospital in Bihar presenting with the thyroid swelling and its histopathological correlation was done in 105 patients.

Results and Observations:

Out of 238 patients with thyroid swelling, majority were females (196) and in younger age group (n = 104 [43.6%], 21–40 years). In 224 cases, adequate smears for cytological interpretation were obtained. Among them, colloid goiter was the most common lesion. Of these, 105 cases were surgically treated, and tissue was submitted for histopathological examination, which showed 97 nonneoplastic lesions and eight neoplastic lesions.

Conclusion:

FNAC is rapid, simple, safe, and cost-effective diagnostic modality in the investigation of thyroid disease with high sensitivity, specificity, and accuracy. It can be used as an excellent first-line method for investigating the nature of lesion. Bethesda system is very useful as it is simplified, systematic, standardized system for reporting thyroid cytopathology, which provides better communication between cytopathologist and clinicians, leading to more consistent management approach.

Comparison of Ultrasound-Guided Fine-Needle Cytology Quality in Thyroid Nodules with 22-, 23-, and 25-Gauge Needles

Objective

To compare the cytology quality of ultrasound-guided fine-needle biopsy in thyroid nodules with 22-, 23-, and 25-gauge (G) needles prospectively.

Methods

A total of 240 consecutive nodules underwent ultrasound-guided fine-needle aspiration (USG-FNA) and 240 nodules underwent ultrasound-guided fine-needle capillary (USG-FNC) were included in this prospective study from October 2014 to February 2016. Each nodule was sampled using 22 G, 23 G, and 25 G needle according to designed orders, and 1240 smears were finally obtained. Cytology quality was scored by a cytologist blinded to needle selection.

Results

In USG-FNA, the average scores and standard deviations were 5.50 ± 2.87 for 25 G needles, 4.82 ± 2.95 for 23 G needles, and 5.19 ± 2.81 for 22 G needles. In USG-FNC, the average scores and standard deviations of each group were 5.12 ± 2.69 for 25 G, 4.60 ± 2.90 for 23 G, and 4.90 ± 2.90 for 22 G needles. The specimen quality scores of 25 G group were significantly higher than that of 23 G group (P < 0.017) in both USG-FNA and USG-FNC. However, the differences were not statistically significant in nondiagnostic rate using different gauge of needles (P > 0.017 for all).

Conclusions

25 G needles obtained the highest scores of sample quality in thyroid FNA and FNC comparing with 22 G and 23 G needles. 25 G needle should be first choice of thyroid FNA and FNC in routine work.

Hydrodissection: A Novel Approach for Safe Core Needle Biopsy of Small High-Risk Subcapsular Thyroid Nodules

PURPOSE

To evaluate the safety and effectiveness of core needle biopsy (CNB) under the assistance of hydrodissection (HDS).

MATERIALS AND METHODS

Of 2325 patients requiring biopsy of thyroid lesions, 21 high-risk patients with subcapsular nodules smaller than 10 mm were recruited into this study. All patients underwent HDS with 0.9% saline solution followed by ultrasound (US)-guided CNB with an 18-gauge semi-automated biopsy needle. The separation success rate (SSR) of the HDS, technical success rate (TSR) of CNB, histopathologic success rate (HSR), and complications were assessed.

RESULTS

Both the SSR of HDS and TSR of CNB were 100% (21/21). The HSR of the thyroid nodules was 85.7% (18/21). No major complications were recorded.

CONCLUSION

HDS before CNB can successfully lead to safe biopsy of small subcapsular thyroid nodules.

LEVEL OF EVIDENCE

Level 4, Case Series.

Clinical and pathologic features for predicting malignancy in thyroid follicular neoplasms

Background

The cytologic findings of follicular neoplasm do not distinguish between benign follicular adenoma and follicular thyroid carcinoma (FTC). The objective of this retrospective study was to identify clinical and cytologic/pathologic features to predict malignancy in patients preoperatively diagnosed with follicular neoplasms.

Methods

In total, 416 patients with follicular neoplasms who underwent thyroidectomy were reviewed at Seoul St. Mary's Hospital (Seoul, Korea) from January 2010 to June 2018. Clinicopathological features were analyzed retrospectively by complete medical chart review and pathologic slide review.

Results

Thyroid malignancy/noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) was diagnosed in 209 patients (50.2%). In total, 59 patients (14.2%) were diagnosed with FTC, 55 patients (13.3%) were diagnosed with follicular variant papillary thyroid carcinoma (fvPTC). The number of patients with PTC-related nuclear changes was higher in the malignancy/NIFTP group than in the benign group (16.3% vs. 1.9%, P<0.001). Multivariate analysis indicated that the significant risk factors for the diagnosis of malignancy/NIFTP include cytologic or pathologic diagnosis with PTC-related nuclear changes, NRAS mutation, and male sex.

Conclusions

The prevalence of malignancy in patients with a preoperative diagnosis of follicular neoplasm was much higher in our study than in previous reports. Cytologic or pathologic PTC-related nuclear changes is a useful predictor of the presence of malignancy. Further studies must be conducted to support our results.

Ultrasound-guided fine-needle aspiration biopsy of thyroid nodules

Fine needle aspiration biopsy (FNAB) remains crucial in the evaluation of thyroid nodules with suspicious clinical findings or ultrasound (US) features suggestive of malignancy. The use of US-guidance for FNAB allows real-time visualization of the needle, but is also highly operator-dependent. Physicians from many specialties (endocrinologists, otolaryngologists/endocrine surgeons, nuclear medicine physicians, radiologists, and pathologists) are involved in the diagnostic workup of thyroid nodules and a standardized and meticulous technique for US-FNAB is essential for lowering the yield of nondiagnostic specimens and false-negative results. This video, therefore, demonstrates a well-proved technique and technical tips to increase the diagnostic results from US-FNAB.

Raman-based cytopathology: an approach to improve diagnostic accuracy in medullary thyroid carcinoma

Medullary thyroid carcinoma (MTC) is a rare form of thyroid malignancy that can be diagnostically challenging on fine needle aspiration (FNA) cytology. Ancillary tests such as elevated serum or immunohistochemical positive calcitonin have been helpful, yet they can occasionally provide false positive results. In search for an alternative method to improve diagnostic accuracy (DA), we applied hyperspectral Raman spectroscopy to characterize the biochemical composition of single cells from MTC and compared their spectral information to cells from other types of thyroid nodules. Hyperspectral Raman images of 117 MTC single cells from digested tissue were obtained with a line-scan hyperspectral Raman microscope and compared to 127 benign and 121 classic variant of papillary thyroid carcinoma (CVPTC) cells. When principal component analysis and linear discriminant analysis were used to classify the spectral data, MTC cells were differentiated from benign and CVPTC cells with 97% and 99% DA, respectively. In addition, MTC cells exhibited a prominent Raman peak at 1003 cm^-1, whose intensity is 84% and 226% greater on average than that observed in benign and CVPTC cells, respectively. When specifically utilizing only this peak as a spectral marker, MTC cells were separated from benign and CVPTC cells with 87% and 95% DA, respectively. As this peak is linked to phenylalanine, which is known to be associated with calcitonin release in thyroid parafollicular cells, the increased intensity further suggests that this Raman peak could potentially be a new diagnostic marker for MTC. Furthermore, preliminary data from MTC cells (n=21) isolated from a simulated FNA procedure provided similar Raman signatures when compared to single cells from digestion. These results suggest that "Raman-based cytopathology" can be used as an adjunct technique to improve the diagnostic accuracy of FNA cytopathology at a single cell level.

Cytopathologic criteria and size should be considered in comparison of fine-needle aspiration vs. core-needle biopsy for thyroid nodules: results based on large surgical series

PURPOSE

To evaluate and compared the diagnostic performances of FNA and CNB using various cytopathologic criteria and size subgroups to see how the comparison results differ accordingly.

METHODS

From May 2012 to May 2019, 8187 thyroid nodules in 8139 patients who had undergone preoperative US-guided FNA or CNB at outside clinics were included in this retrospective study (mean size: 11.9 ± 9.5 mm). Preoperative US-FNA was performed in 7496 (91.6%) nodules and US-CNB was performed in 691 (8.4%) nodules. Propensity score matching was used to compare the sensitivities between FNA and CNB in diagnosis of malignancy and neoplasm according to different cytologic test criteria.

RESULTS

Of the 8187 thyroid nodules, 7833 (95.7%) were malignant and 354 (4.3%) were benign. Mean size of the thyroid nodules in the CNB group was significantly larger than the FNA group, 15.7 ± 12.7 mm vs. 11.6 ± 9.0 mm, respectively (P < 0.001). After matching, sensitivity in the CNB group were significantly higher in the total population, and in subgroups <10 mm for criteria 1 and 2 (all P < 0.05, respectively). No significant differences were seen between the sensitivities of FNA and CNB for nodules ≥10 mm regardless of criteria in diagnosis of malignancy or neoplasm (all P > 0.05, respectively).

CONCLUSIONS

Results comparing sensitivities between FNA and CNB differ according to the different cytopathologic criteria used for calculation. CNB has significantly higher sensitivity to FNA in subcentimeter nodules when using criteria 1 or 2. Diagnostic sensitivities did not show significant differences for nodules ≥10 mm regardless of the cytopathologic criteria used, that should be considered in selecting biopsy methods.

Radial Basis Function Artificial Neural Network for the Investigation of Thyroid Cytological Lesions

Objective

This study investigates the potential of an artificial intelligence (AI) methodology, the radial basis function (RBF) artificial neural network (ANN), in the evaluation of thyroid lesions. Study Design. The study was performed on 447 patients who had both cytological and histological evaluation in agreement. Cytological specimens were prepared using liquid-based cytology, and the histological result was based on subsequent surgical samples. Each specimen was digitized; on these images, nuclear morphology features were measured by the use of an image analysis system. The extracted measurements (41,324 nuclei) were separated into two sets: the training set that was used to create the RBF ANN and the test set that was used to evaluate the RBF performance. The system aimed to predict the histological status as benign or malignant.

Results

The RBF ANN obtained in the training set has sensitivity 82.5%, specificity 94.6%, and overall accuracy 90.3%, while in the test set, these indices were 81.4%, 90.0%, and 86.9%, respectively. Algorithm was used to classify patients on the basis of the RBF ANN, the overall sensitivity was 95.0%, the specificity was 95.5%, and no statistically significant difference was observed.

Conclusion

AI techniques and especially ANNs, only in the recent years, have been studied extensively. The proposed approach is promising to avoid misdiagnoses and assists the everyday practice of the cytopathology. The major drawback in this approach is the automation of a procedure to accurately detect and measure cell nuclei from the digitized images.

TCR-Seq Identifies Distinct Repertoires of Distant-Metastatic and Nondistant-Metastatic Thyroid Tumors

CONTEXT

Malignant thyroid tumor with distant metastasis is associated with poor outcome. Early detection of distant metastasis is of great clinical importance.

OBJECTIVE

Thyroid tumor infiltrated with T cells can serve as a biomarker for monitoring metastasis.

DESIGN

A retrospective analysis was performed of patient clinical samples collected between 2012 to 2018, using T-cell receptor sequencing (TCR-seq) for clinical exploration.

SETTING

This study took place at Zhejiang Cancer Hospital.

PATIENTS

Sixty-eight patients with papillary thyroid cancer (PTC) (distinct metastatic status) and 21 patients with benign nodules were enrolled. All patients had not received any treatment before surgery.

MAIN OUTCOME MEASURE

The characteristics of TCRβ complementary-determining region 3 (CDR3) for each patient were determined by high-throughput sequencing.

RESULTS

The TCRβ diversity of malignant tumors is significantly higher than benign nodules both in blood and tumor samples (Shannon index, blood, P < .01; tumor, P < .001). The malignant tumors with distant metastasis or invasiveness showed lower TCRβ diversity than nonmetastasis (Shannon index, P < .01) or noninvasive (Shannon index, P < .01) malignant tumors. Analysis of the Morisita-Horn similarity index indicated significant TCRβ repertoire similarity between tumor and blood in distant-metastatic patients (comparison with nonmetastasis, P < .05). According to the discrepancy of the CDR3 among patients with different clinicopathological status, the classifier was constructed to discriminate distant-metastatic individuals. A promising area under the curve value of 83.8% was obtained with the number of overlapping CDR3 clonotypes.

CONCLUSION

The availability and reliability of TCR-seq render it prospective to translate these intrinsic attributes into clinical practice for monitoring distant metastasis in PTC patients.

Should we wait 3 months for a repeat aspiration in non-diagnostic/indeterminate thyroid nodules? A cancer centre experience

INTRODUCTION

The Bethesda System recommends repeat fine needle aspiration (rFNA) as a management option for nodules classified under the non-diagnostic (ND) and atypia of undetermined significance (AUS/FLUS) categories. We evaluated the impact of an rFNA in diagnostic resolution and the role of early (≤3 months) vs delayed (more than 3 months) rFNA of nodules initially diagnosed as ND and AUS/FLUS.

METHODS

We retrospectively collected all thyroid FNA performed in a 4-year period with repeat aspiration. For cases initially signed out as ND or AUS/FLUS, diagnostic resolution was defined as a change to a Bethesda System category other than these two on rFNA. Comparison and regression models were fitted to identify the impact of time of rFNA on diagnostic resolution.

RESULTS

In total, 184 cases were initially assigned as ND and 143 as AUS/FLUS, with overall diagnostic resolution rates for the reassessment of these nodules calculated at 70.1% and 62.9%, respectively. For ND cases, time of rFNA was not significantly associated with diagnostic resolution (P > .05). For AUS/FLUS nodules, however, repeat aspiration performed in more than 3 months after the initial diagnosis was 2.5 times more likely to achieve a resolution in diagnosis than early rFNA (P = .024).

CONCLUSIONS

Repeat aspiration of ND and AUS/FLUS nodules helped define diagnosis for the majority of cases, being highly effective in determining correct patient management. For AUS/FLUS nodules, repeat aspiration performed more than 3 months after the initial diagnosis was associated with a higher diagnostic resolution.

Cost effectiveness of intraoperative pathology in the management of indeterminate thyroid nodules

Objective This study aims to determine the cost effectiveness of rapid frozen section (RFS) for indeterminate thyroid nodules. Materials and methods A retrospective chart review was conducted between January 2009 and June 2013 at a tertiary care institution. Main outcomes were number needed to treat, RFS efficacy, and cost-savings of avoiding second completion thyroidectomy. Cost-effectiveness was estimated using 2015 Medicare reimbursement rate. Results Out of 1,114 patients undergoing thyroid surgery, 314 had preoperative AUS/FLUS cytopathology and subsequent thyroid lobectomy with RFS. RFS identified 13 of the 32 patients with malignancy resulting in a total thyroidectomy. 19 of the 29 malignancies not detected by RFS were papillary microcarcinomas. Conclusions Completion thyroidectomy was avoided in 1 out of every 24 patients resulting in cost-savings of $ 80.04 per patient. In the era of outpatient thyroid surgery, intraoperative RFS for indeterminate thyroid nodules is cost-effective.

A Bethesda-like system for breast cytopathology: A retrospective assessment two decades on

Fine-needle aspiration biopsy (FNAB) has been used for many decades in the investigation of breast lesions. Originally, cases were signed out using the categories benign and malignant. The benign category contained specimens showing fibrocystic change as well as benign neoplasms such as fibroadenoma. The malignant category contained carcinomas, lymphomas, and phyllodes tumors with specific diagnoses often given in place of the term malignant. Categorization was less clear when the cytopathologists could not definitively separate benign from malignant. This led to the use of terms, such as atypical, suspicious for malignancy, and atypical suspicious with variable definitions and utilization among cytopathologists. In 1997, a uniform approach to breast FNAB was proposed with well-defined diagnostic categories and criteria. This system foreshadowed the recent International Academy of Cytology Standardized Reporting System for Breast Fine-Needle Aspiration Biopsy. These two systems are compared and contrasted.

Is thyroid core needle biopsy a valid compliment to fine-needle aspiration?

Fine-needle aspiration (FNA) has long been considered the first and an important diagnostic tool in the evaluation of thyroid nodules. The advantages of FNA include simplicity, safety, cost-effectiveness, high diagnostic accuracy, and low complication rate. Nevertheless, limitations associated with FNA include a substantial rate of inconclusive results and indeterminate interpretations. Therefore, core needle biopsy (CNB) of the thyroid gland has been proposed as a complementary or even alternate diagnostic method to evaluate thyroid nodules. Although controversial, a growing number of researchers have reported CNB to be an effective and safe sampling method for thyroid nodules, especially for cases with inadequate or indeterminate FNA yields. Skeptics highlight local pain and bleeding risk. Supporters highlight the potential likelihood of overcoming FNA limitations by obtaining a larger amount of tissue and using architecture and cellular details to guide possible ancillary testing. This review evaluates the indications, advantages, and disadvantages of CNB as compared with FNA of the thyroid gland.

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

OBJECTIVE

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Malignancy rates for Bethesda III and IV thyroid nodules: a retrospective study of the correlation between fine-needle aspiration cytology and histopathology

BACKGROUND

Fine-needle aspiration cytology (FNAC) has become a well-established modality in the diagnosis, staging and follow-up of thyroid nodules. FNAC outcomes are routinely classified using the Bethesda System for Reporting Thyroid Cytopathology (BSRTC), facilitating appropriate clinical management. Bethesda categories III and IV encompass varying risks of malignancy. This retrospective study established a possible association between these cytological categories and malignancy rates in patients treated at a single institution.

METHODS

Over a 6-year period, 11,627 FNAC procedures were performed on thyroid nodules. Of these, 814 (59.63%) patients were submitted to thyroidectomy. The nodules of 108 patients were classified as Bethesda category III and 47 patients as Bethesda category IV. Patient data were reviewed to establish a correlation between the FNAC results and the final histopathological analyses.

RESULTS

The rates of malignancy among patients who underwent surgery were 25% for category III and 27.6% for category IV, with no significant differences between categories (p = 0.67). The pathological parameters of malignant nodules, namely tumour type, size, encapsulation, invasion into the thyroid capsule, extrathyroidal extension and lymphovascular invasion did not significantly differ between the groups (p > 0.05).

CONCLUSIONS

This paper provides a more precise correlation of malignancy rates with thyroid nodules classified as Bethesda categories III and IV, as our findings are comparable to the literature, giving malignancy rates ranging from 10 to 30% for category III and 25-40% for category IV. Use of the BSRTC is heterogeneous across institutions, and there is some degree of subjectivity in the distinction between categories III and IV; therefore, it is crucial to estimate the rates of malignancy at each institution. Molecular assays are of increasing importance in determining the need for surgical intervention for thyroid lesions. Gene expression assays using FNAC material may demonstrate a high predictive value for cytologically indeterminate thyroid nodules diagnosed as Bethesda classes III and IV.

Diagnostic accuracy of preoperative palpation- versus ultrasound-guided thyroid fine needle aspiration cytology: an observational study

BACKGROUND

Thyroid fine needle aspiration (FNA) is the mainstay for diagnosis of malignancy, and is an integral part of current thyroid nodule assessment. The present study analyzes the diagnostic accuracy of palpation-directed versus ultrasound guided fine-needle aspiration in patients who underwent surgery for thyroid nodules.

METHODS

A retrospective chart review of all consecutive patients who had FNA biopsy (palpation or ultrasound guided) of thyroid nodules and underwent thyroid gland surgery between 1998 and 2014 was conducted. The FNA findings of the palpation-guided and ultrasound-guided groups were compared for baseline characteristics. Moreover, the diagnostic accuracy of FNA findings and surgical histopathology results were analyzed.

RESULTS

A total of 1174 patients were included in the study with a mean age of 46.3 ± 11.7 years and the majority were females (75.5%). Among the study population, 392 (33.4%) patients underwent US-guided FNA; 570 (48.6%) had palpation-guided FNA in clinic and no FNA was done in 212 (18%) cases. Patients underwent US-guided FNA were more likely to have suspicion of malignancy (p = 0.001), and had indeterminate findings (p = 0.001). On the other hand, palpation-guided FNA group had significantly higher frequency of benign cytology (p = 0.001). With respect to the suspicion for malignancy as well as malignancy, the US-guided group had a similar diagnostic accuracy in comparison to the palpation group. The proportion of malignancy finding on US-guided FNA (8.9%) was higher than the palpation-guided FNA (6.4%) that had been confirmed on postoperative histopathological examination (p = 0.95).

CONCLUSION

The present study demonstrates higher sensitivity of US-guided thyroid FNA biopsies over palpation-guided FNA for the suspicion of malignancy; however, the accuracy is comparable. Moreover, both groups showed more postoperative malignancy in the benign and unsatisfactory categories than predicted in the Bethesda system. Further prospective studies are needed to underpin a realistic correlation between FNA and final histopathology reports.

2019 Practice guidelines for thyroid core needle biopsy: a report of the Clinical Practice Guidelines Development Committee of the Korean Thyroid Association

Ultrasound-guided core needle biopsy (CNB) has been increasingly used for the pre-operative diagnosis of thyroid nodules. Since the Korean Society of the Thyroid Radiology published the ‘Consensus Statement and Recommendations for Thyroid CNB’ in 2017 and the Korean Endocrine Pathology Thyroid CNB Study Group published ‘Pathology Reporting of Thyroid Core Needle Biopsy’ in 2015, advances have occurred rapidly not only in the management guidelines for thyroid nodules but also in the diagnostic terminology and classification schemes. The Clinical Practice Guidelines Development Committee of the Korean Thyroid Association (KTA) reviewed publications on thyroid CNB from 1995 to September 2019 and updated the recommendations and statements for the diagnosis and management of thyroid nodules using CNB. Recommendations for the resolution of clinical controversies regarding the use of CNB were based on expert opinion. These practical guidelines include recommendations and statements regarding indications for CNB, patient preparation, CNB technique, biopsy-related complications, biopsy specimen preparation and processing, and pathology interpretation and reporting of thyroid CNB.

Comparison of Number of Passes and Cytopathological Specimen Adequacy for Thyroid Fine-Needle Aspiration Biopsy in the Absence of an On-Site Pathologist

AIM

Ultrasound-guided fine-needle aspiration biopsy (FNAB) is a reliable, minimally invasive diagnostic method with high sensitivity and specificity in the evaluation of thyroid nodules. Our aim in this retrospective study was to determine if there was a difference in the adequacy ratio based on the number of needle passes in the thyroid FNABs in the absence of rapid on-site evaluation (ROSE) by the pathologist and to determine the optimal needle pass number for FNAB.

METHODS

Between November 2018 and February 2019, thyroid FNABs of 121 (99 female, 22 male) patients were evaluated retrospectively. Samples for each biopsy were numbered according to the order of retrieval, and 4 pairs of slides were prepared by the radiologist without on-site microscopic evaluation. Cytological results were determined according to the Bethesda classification.

RESULTS

The rate of adequacy in the first, second, third, and fourth passes were 76.0, 82.6, 77.7, and 71.2%, respectively. No statistically significant difference was found between these four groups in terms of adequacy (p = 0.21). The adequacy rates of the 1st, 1st+2nd, 1st+2nd+3rd, and cumulative evaluation of all four biopsies were 76.0, 87.6, 90.1, and 91.7%, respectively (p = 0.001). A statistically significant difference was found in the comparison of the 1st biopsy and the cumulative 1st+2nd biopsy in terms of adequacy rates (p = 0.019). However, there was no statistically significant difference between the cumulative 1st+2nd biopsy and the cumulative 1st+2nd+3rd biopsy in terms of adequacy rates (p = 0.54).

CONCLUSIONS

In cases where ROSE cannot be performed, we recommend a minimum of 2 and a maximum of 3 needle entries for FNAB adequacy with the right technique and preparation.

Risk of malignancy in the various categories of the UK Royal College of Pathologists Thy terminology for thyroid FNA cytology: A systematic review and meta-analysis

BACKGROUND

The UK Royal College of Pathologists Thy terminology for reporting thyroid fine-needle aspiration cytology (FNAC), first published in 2009 is used throughout the United Kingdom and Ireland, in some parts of Italy and Switzerland and elsewhere. There is no review of the literature or meta-analysis of the risk of malignancy (ROM) in the various categories of the UK Thy terminology. The goal of this study was to establish the published ROM for each Thy category and compare the results with other existing terminology systems for which similar meta-analyses are available.

METHODS

A comprehensive literature search of online databases was conducted in May 2019 to examine the ROMs for histologically proven nodules with preoperative FNAC classified according to the UK Thy terminology.

RESULTS

Twenty-five articles were identified that showed results of both cytology and histology. Twelve of these articles were excluded to prevent a selection bias because they showed data in just 1 Thy category. In the remaining 13 articles, the pooled ROMs were as follows: Thy1, 12% (95% confidence interval [CI], 5%-22%); Thy2, 5% (95% CI, 3%-9%); Thy3, 22% (95% CI, 18%-26%); Thy3a, 25% (95% CI, 20%-31%); Thy3f, 31% (95% CI, 24%-39%); Thy4, 79% (95% CI, 70%-87%); and Thy5, 98% (95% CI, 97%-99%).

CONCLUSIONS

This meta-analysis shows results comparable to those of meta-analyses of other internationally recognized reporting terminologies for the pooled ROMs for surgically excised nodules in the various Thy reporting categories. There is comparatively little difference (only 6%) between the pooled ROMs of Thy3a and Thy3f surgically excised nodules.

Evaluation of thyroid nodules classified as Bethesda category III on cytology and their malignancy rate: An institutional experience

Background:

Thyroid gland nodules are common and fine-needle aspiration (FNA) is the gold standard for screening those nodules. The Bethesda system for reporting thyroid cytolopathology standardized reporting thyroid nodules aspirations, but atypia of undetermined significance or follicular lesion of undetermined significance (Bethesda category III) was the most controversial category. The aim of our study is to review our institutional experience and analyze the clinical implications of making a diagnosis of AUS/FLUS (Bethesda category III).

Methods:

This is a retrospective study of an 889 thyroid FNAs from 825 patients in Salmaniya Medical Complex, during (January 2013–December 2017).

Results:

The most common cause for designating cases as AUS/FLUS (Bethesda category III) was the presence of features suggestive of papillary thyroid carcinoma, but not quite fulfilling the criteria for such diagnosis. Ninety-six cases were diagnosed as AUS/FLUS (10.7%), in which 26 (27%) patients underwent surgery without repeating the FNA, 25 (26%) underwent a second FNA and 43 (44.7%) patients were followed up by ultrasound. On repeating the FNA, 1 (4%) was unsatisfactory, 13 (52%) were benign, 10 (40%) were AUS/FLUS, and only 1 (4%) was categorized as malignant. Thirty cases were surgically excised, in which 4 (13.3%) were diagnosed as follicular adenoma, 2 (6.6%) as Hurthle cell adenoma, 9 (30%) as multinodular goiter, 5 (16.6%) as multinodular goiter with Hashimoto thyroiditis, 1 (3.3%) as colloid nodule with Hashimoto thyroiditis, and 9 (30%) as papillary thyroid carcinoma. Among all the cases diagnosed initially as AUS/FLUS (Bethesda category III), 9 (9.3%) cases were diagnosed as papillary thyroid carcinoma.

Conclusion:

Diagnostically, we almost meet the international standards of designating cases with AUS/FLUS (Bethesda category III) and approximate the risk of malignancy. However, the clinical management's guidelines should be followed to decrease the risk of unnecessary surgeries and their complications. There is a statistically significant correlation between the age and gender with the final histopathology report, respectively.

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

Objectives

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

Method

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

Results

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

Conclusions

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

Core needle biopsy in the management of thyroid nodules with an indeterminate fine-needle aspiration report

Ultrasonography (US)-guided fine-needle aspiration biopsy (FNAB) cytology is widely used but is limited due to its pathologically indeterminate results in diagnosing thyroid nodules. Recently, US-guided core-needle biopsy (CNB) was introduced as an effective and safe technique for diagnosing indeterminate thyroid nodules. Using CNB, information about architectural histologic structure such as nodule capsule or more immunochemical staining can be obtained which lead to a more accurate diagnosis. Up to 98% of indeterminate thyroid lesions can be classified as malignant or benign when CNB is used for follow-up analysis. Other evidences revealed the effectiveness of CNB in reducing inconclusive results and improving the diagnostic performance of thyroid nodules initially diagnosed as AUS/FLUS by FNAB. In this review, we investigate how to deal with indeterminate thyroid nodules diagnosed by FNAB and determine how CNB has a role in diagnosing these indeterminate thyroid nodules.

Risk of Malignancy According to the Sub-classification of Atypia of Undetermined Significance and Suspicious Follicular Neoplasm Categories in Thyroid Core Needle Biopsies

The objective of this study was to evaluate the risk of malignancy (ROM) associated with atypia of undetermined significance (AUS) and suspicious follicular neoplasm (SFN) core needle biopsy (CNB) categories after further sub-classification. Data from 2267 thyroid nodules evaluated by ultrasound-guided CNB, from January to December 2015, were retrospectively reviewed. AUS nodules (n = 556) were sub-classified as follows: (1) architectural atypia (AUS-A; n = 369, 66.4%), (2) cytologic atypia (AUS-C; n = 35, 6.3%), (3) cytologic/architectural atypia (AUS-C/A; n = 85, 15.3%), or (4) oncocytic atypia (AUS-O; n = 67, 12.1%). SFN nodules (n = 172) were sub-classified as follows: (1) architectural atypia only (SFN-A; n = 110, 64%), (2) cytologic/architectural atypia (SFN-C/A; n = 24, 14%), or (3) oncocytic atypia (SFN-O; n = 38, 22%). Diagnostic surgery was performed in 162 (30.2%) AUS cases and 105 (61%) SFN cases. The ROM of each sub-category was evaluated. The overall ROM was 15.3-52.5% in AUS nodules and 35.5-58.1% in SFN nodules. The ROM was higher in the AUS-C (22.9-88.9%) and AUS-C/A (32.9-90.3%) groups than AUS-A (11.9-40%) and AUS-O (7.5-41.7%). In the SFN category, ROM in the SFN-C/A group was also higher than SFN-A or SFN-O (37.5-75%, 40-57.9%, and 21.1-47.1%, respectively). Our study shows that the ROM was higher in AUS or SFN sub-categories with cytologic atypia than those without cytologic atypia. Because of the heterogeneous nature of AUS and SFN categories, sub-classification may be a more effective approach for risk stratification, allowing optimal management of patients with thyroid nodules.

Thyroid nodules: diagnosis and management

Thyroid nodules are common. Their importance lies in the need to assess thyroid function, degree of and future risk of mass effect, and exclude thyroid cancer, which occurs in 7-15% of thyroid nodules. There are four key components to thyroid nodule assessment: clinical history and examination, serum thyroid stimulating hormone (TSH) measurement, ultrasound and, if indicated, fine-needle aspiration (FNA). If the serum TSH is suppressed, a thyroid scan with ⁹⁹Tc can distinguish between a solitary hot nodule, a toxic multinodular goitre or, less commonly, thyroiditis or Graves' disease within a coexisting nodular thyroid. Scintigraphically cold nodules are evaluated in the same way as in the setting of normal or elevated serum TSH levels. Thyroid ultrasonography should be performed only for palpable goitre and thyroid nodules and by specialists with expertise in thyroid sonography. Routine thyroid cancer screening is not recommended, except in high risk individuals, as the detection of early thyroid cancer has not been shown to improve survival. FNA may be performed for nodules ≥ 1.0 cm depending on clinical and sonographic risk factors for thyroid cancer. FNA specimens should be read by an experienced cytopathologist and be reported according to the Bethesda Classification System. Molecular analysis of indeterminate FNA samples has potential to better discriminate benign from malignant nodules and thus guide management. Surgery is indicated for FNA findings of malignancy or indeterminate cytology when there is a high risk clinical context. Surgery may also be indicated for suspicion of malignancy; larger nodules, especially with symptoms of mass effect; and in some patients with thyrotoxicosis.

Clinical Diagnostic Evaluation of Thyroid Nodules

The presence of a thyroid nodule may be recognized by the patient or the clinician on palpation of the neck or it may be an incidental finding during an imaging study for some other indication. The method of detection is less important, however, than distinguishing benign lesions from more aggressive neoplasms. This article outlines the diagnostic algorithm for the evaluation of thyroid nodules including biochemical testing, imaging, and, when appropriate, fine-needle aspiration. In addition, the authors review the natural history of benign nodules, follow-up strategies, and indications for repeat aspiration.

The Current Histologic Classification of Thyroid Cancer

Thyroid cancers of follicular cell derivation provide excellent phenotype-genotype correlations. Current morphologic classifications are complex and require simplification. Benign adenomas have follicular or papillary architecture and bland cytology. Well-differentiated thyroid carcinomas exhibit follicular architecture, expansile growth, and variable cytologic atypia and invasiveness; low-risk tumors have excellent prognosis after surgical resection whereas widely-invasive and angioinvasive tumors warrant total thyroidectomy and radioablation. Papillary carcinoma is less differentiated; indolent microcarcinomas can be managed by active surveillance, whereas clinical lesions with local or distant spread require therapy. Progression gives rise to poorly differentiated and anaplastic carcinomas that are less common but far more aggressive.

Optimal needle size for thyroid fine needle aspiration cytology

Concerning the needle size for thyroid fine needle aspiration cytology (FNAC), 25-27-gauge needles are generally used in Western countries. However, in Japan, the use of larger needles (21-22-gauge needles) is common. The aim of our study was to determine the optimal needle size for thyroid FNAC. We performed ultrasound-guided FNAC for 200 thyroid nodules in 200 patients using two different-sized needles (22 and 25 gauge). For each nodule, two passes with the different-sized needles were performed. The order of needle sizes was reversed for the second group of 100 nodules. The second aspiration was more painful than the first, regardless of the needle size. An association with more severe blood contamination was more frequently observed with the use of 22-gauge needles (32.0%) than with the use of 25-gauge needles (17.5%) and in the second aspiration (37.5%) than in the initial aspiration (12.0%). The initial aspiration samples were more cellular than the second aspiration samples. Regarding the unsatisfactory and malignancy detection rates, there was no statistical difference between the needles. In three of seven markedly calcified nodules, it was difficult to insert 25-gauge needles into the nodules. In terms of the diagnostic accuracy and pain, either needle size can be used. We recommend using 22-gauge needles for markedly calcified nodules because 25-gauge needles bend more easily in such cases. We demonstrated that the initial aspiration tended to obtain more cellular samples and to be less contaminated. Thus, the initial aspiration is more important and should be closely attended.

Pathological diagnosis of thyroid nodules based on core needle biopsies: comparative study between core needle biopsies and resected specimens in 578 cases

BACKGROUND

Pathological diagnosis based on core needle biopsy (CNB) should be different from a resected specimen because it is difficult to apply the histological criteria established for resected specimens to CNB due to sampling limitations. A pathological classification for thyroid nodule on CNB was first proposed by the Korean Group in 2015. The objective of this study was to test the reliability and clinical value of this proposal.

METHODS

According to the Korean proposal, the CNB diagnoses were categorized into unsatisfactory, benign, indeterminate, follicular neoplasm, suspicious for malignancy and malignant. A comparative study between the diagnoses of CNB and resected specimens was performed.

RESULTS

The consistency was moderate (κ = 0.448). Combined indeterminate, suspicious for malignancy and malignant into a single group collectively referred to as "malignant" with the remaining merged into "others", CNB demonstrated a 95.93% sensitivity, 97.30% specificity, 62.07% accuracy, 99.81% positive predictive value (PPV) and 62.07% negative predictive value (NPV) for preoperative malignancy evaluation.

CONCLUSIONS

The Korean proposal for pathological classification of thyroid nodules on CNB is objective, operable and highly valuable.

Malignancy rate of atypia of undetermined significance/follicular lesion of undetermined significance in thyroid nodules undergoing FNA in a suburban endocrinology practice: A retrospective cohort analysis

BACKGROUND

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) was created to establish a standard terminology regarding thyroid nodules that can be shared between endocrinologists, pathologists, radiologists, and surgeons. Since its inception and use in 2009, multiple large hospitals and academic institutions have performed retrospective studies to compare their classification rates, specifically those of atypia of undetermined significance (AUS) and follicular lesion of undetermined significance (FLUS), with the recommended rates created by the National Cancer Institute. The current study compared AUS/FLUS rates at a private suburban endocrine practice with those of previous publications from large institutions and the rates established by the National Cancer Institute.

METHODS

Charts from 893 patients with fine-needle aspiration (FNA) performed in 2015 were reviewed. Data specific to thyroid aspirates classified as AUS/FLUS were organized into whether patients underwent surgery, underwent subsequent repeat FNA, or required continued observation. These results then were calculated to reveal the rate of malignancy in the AUS/FLUS category with surgical pathology in the study institution.

RESULTS

A total of 893 patients underwent FNA, with 43 patients (4.82%) shown to have AUS/FLUS. A total of 21 patients proceeded to undergo thyroidectomy or lobectomy, with 7 patients (33.3%) found to have papillary or follicular thyroid carcinoma.

CONCLUSIONS

The rate of use of the AUS/FLUS category for thyroid nodules examined at the study institution was found to be within the recommended range set forth by TBSRTC. However, the malignancy rates on histopathology in the study institution were found to be higher than the new proposed malignancy rates from TBSRTC published in 2017. This finding is comparable to those of multiple other community and academic institutions performed prior to and after institution of the new guidelines.