Pattern of thyroid lesions and role of fine needle aspiration cytology (FNA) in the management of thyroid enlargement: a retrospective study from a teaching hospital in Riyadh

The prevalence and associated predictors for Bethesda III-VI for reporting thyroid cytopathology in Royal Commission Hospital, Kingdom of Saudi Arabia

BACKGROUND

Thyroid cancer is increasing globally and is currently the most prevalent endocrine malignancy. Recent data show an increase in the incidence of thyroid cancer in the Kingdom of Saudi Arabia (KSA). Thyroid ultrasound and fine-needle aspiration cytology (FNAC) are the cornerstones in managing thyroid nodules. We conducted this study to evaluate the prevalence and the associated predictors for thyroid nodule Bethesda III-VI in eastern KSA.

METHODS

A retrospective study was conducted between January 2015 and 31 August 2021. The participants were recruited patients who received a thyroid ultrasound and ultrasound-guided thyroid FNAC, using the thyroid imaging reporting and data system (TI-RADS) and the Bethesda Classification, respectively.

RESULT

Three hundred and ten patients who underwent thyroid FNAC were enrolled in the study. The median (interquartile, IQR) age was 47.0 (20.0) years, and 266 (85.8%) of them were females. The median (IQR) body mass index was 30.2 (7.6) kg/m². Out of these participants, 64.8% were euthyroid, 27.4% had hypothyroidism and 7.7% had hyperthyroidism. The ACR TI-RADS-3, 4 and 5 were 51.3%, 46.1% and 2.6%, respectively. The Bethesda outcome of thyroid FNAC I-VI was 5.2%, 63.9%, 15.5%, 5.8%, 3.5% and 6.1%, respectively. The risk for malignancy (Bethesda III-VI) was documented in 31.0% and atypia of undetermined significance was most prevalent (15.5%). A higher ACR TI-RADS score was associated with a higher risk of malignancy: ACR TI-RADS-3 (20.8%), ACR TI-RADS-4 (39.2%) and ACR TI-RADS-5 (87.5%). In a multivariate analysis, only the ACR TI-RADS score was significantly associated with the outcome of thyroid FNAC: ACR TI-RADS-4 [OR = 2.59 (95% CI = 1.54-4.36)] and ACR TI-RADS-5 [OR = 29.03 (95% CI = 3.44-245.07)].

CONCLUSION

There was a high prevalence of Bethesda III-VI and atypia of undetermined significance was most prevalent. A thyroid ultrasound report for TI-RADS was significantly associated with the outcome of thyroid FNAC and is a reliable tool in the absence of molecular testing for thyroid cancer.

The Bethesda System for Reporting Thyroid Cytopathology: A Retrospective Review of its Diagnostic Utility at Johns Hopkins Aramco Healthcare, Saudi Arabia

PURPOSE

Fine needle aspiration (FNA) is the gold standard for assessment of thyroid nodules, with the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) used to predict the malignancy risk of these nodules. Our aim was to evaluate the diagnostic utility of the TBSRTC for a Saudi population, by comparing the malignancy risk based on histopathology to FNA-based diagnosis of each of the TBSRTC categories and to previously published malignancy risk in other population.

MATERIALS AND METHODS

This was a retrospective study of the data of 241 patients who underwent FNA assessment of thyroid nodules and surgical resection with histopathology at John Hopkins Aramco Healthcare, Dhahran, Saudi Arabia, between January 2016 and December 2019.

RESULTS

The malignancy risk for each of the TBSRTC categories was as follows: non-diagnostic, 25%, benign; 5.74%; atypia of undetermined significance, 37%; suspicious for follicular neoplasm, 38%; suspicious for malignancy, 100%; and malignant, 95%. Our finding were comparable to previously published malignancy risks, except for a higher rate of malignancy in the benign category at 18% compared to 0-3%.

CONCLUSION

Our findings validate the diagnostic reproducibility of the TBSRTC for a Saudi population, with the risk of malignancy confirmed by histopathological assessment being consistent with those previously reported for other populations.

Nature and outcome of malignant goiter: a revisit

Introduction

the aim of this retrospective study is to review patients with malignant goiter, as regards their nature, demographic characterization, clinical presentation and preoperative histopathological data.

Methods

the study focused on a period of 4 years from December 2015 to January 2019. Patients´ demographic data, clinical presentation, Intra-operative findings, Pre and postoperative histopathological staging and grading were all recorded. Postoperative follow up whether early or late were also included.

Results

a total of 100% (n = 65) patients underwent surgery. The female to male ratio was found to be 5:1 (48 females and 17 males). Solitary nodule was the main clinical presentation in 80% (n = 52) of cases while 20% (n = 13) were multinodular swellings. Papillary carcinoma was recorded in 80% (n = 52) of patients while in 15.4% (n =10) of patients were having follicular carcinoma. The remaining 4.6% (n = 3) suffered of lymphoma; no medullary or anaplastic tumors were reported.

Conclusion

thyroid cancer is the most commonly encountered endocrinal malignancy at our institute. Fine Needle Aspiration Cytology (FNAC) showed a high percentage of reliability in diagnosing thyroid cancer among our series. It is recommended to adapt this technique in initial screening of goiter patients in our local setting.

The bethesda system for reporting thyroid cytopathology: a five-year retrospective review of one center experience

Fine-needle aspiration (FNA) of the thyroid gland is a widely accepted and accurate method for triaging patients with thyroid nodules. Thyroid FNA suffers from a reporting confusion due to multiplicity of category terminologies. To address this, The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) was recently introduced for unifying the terminology and morphologic criteria along with the corresponding risk of malignancy.

OBJECTIVE

The aim of this study was to report the diagnostic utility of TBSRTC at our institution and report the malignancy risk for FNA of thyroid lesions among Saudi patients using this system at KAUH (King Abdulaziz University Hospital), Jeddah, Saudi Arabia.

MATERIALS AND METHODS

A retrospective study identifying 250 thyroid FNAs performed among Saudi patients between Jan 2005-Dec 2010 was undertaken. Cytology specimen data was collected through a computerized search of our cytopathology archives.

RESULTS

Among the 250 thyroid FNAs, 84 were followed by surgical resection. The overall surgical yield of malignancy was 23.8%. The malignancy rate for the 6 categories was as follows: non diagnostic: 20%, benign: 3.1%, atypia of undetermined significance: 50%, suspicious for follicular neoplasm: 20%, suspicious for malignancy: 80%, malignant: 100%.

CONCLUSION

Retrospective classification of FNAs of thyroid lesions among Saudi patients using TBSRTC at KAAUH, Jeddah, Saudi Arabia, validates the diagnostic reproducibility of this system and yields similar results for risk of malignancy as reported by others. However the associated rates found for non diagnostic (20%) raise the possibility of malignancy risk in this category and validate the past observations that sample inadequacy is a common cause of false negative thyroid FNAs.

Divide and rule: cytodiagnosis of thyroid lesions using pattern analysis: a study of 233 cases

Fine needle aspiration cytology (FNAC) of the thyroid is a simple, accurate, fast, economical and safe method for the diagnosis of thyroid lesions on FNA. The objective of this study was application of pattern analysis in the interpretation of thyroid lesions. Two hundred and thirty three cases of thyroid lesion were reviewed, which had histopathological correlation. Smears were classified based on primary (predominant) and secondary (next dominant) pattern and categorized. The variation between combined and final cytological diagnosis was correlated with the histopathological diagnosis. The sensitivity, specificity and diagnostic accuracy for the diagnosis of malignancy were 90.47, 100 and 99.14%. Our study demonstrates the feasibility and applicability of pattern analysis in diagnosing thyroid lesions, which could be easily reproducible.

Application of pattern analysis in fine needle aspiration of solitary nodule of thyroid

BACKGROUND

Various methods are used to arrive at a conclusive diagnosis of thyroid lesions on fine needle aspiration cytology (FNAC). Systemic pattern analysis is one such that can be used to analyze the lesions and divide them into individual categories.

AIMS

To study the application of pattern analysis in the interpretation of solitary thyroid nodule (STN).

MATERIALS AND METHODS

Two hundred and nineteen cases of fine needle aspiration cytology of STN were reviewed along with histopathological correlation. Smears were classified based on primary and secondary patterns. Predominant pattern (primary) was identified and lesion categorized. This was followed by identifying the next dominant pattern (secondary) and recategorization. Cytological diagnosis based on primary and secondary patterns was correlated with the histopathological diagnosis.

RESULTS

Based on pattern analysis, the study had a sensitivity of 66.7% and specificity of 98.9%. The positive predictive value and negative predictive value were 88.9% and 96% respectively and the overall diagnostic accuracy was 95.4%.

CONCLUSIONS

The present study demonstrates the feasibility and applicability of pattern analysis in diagnosing thyroid lesions by FNAC, which could be easily reproducible.

B-RAF V600E mutational analysis of fine needle aspirates correlates with diagnosis of thyroid nodules

Objective: A mutation of B-type RAF kinase (B-RAF) represents the most common genetic alteration in papillary thyroid cancer (PTC), possibly signifying a more aggressive biology. Fine needle aspiration (FNA) represents the most useful initial diagnostic tool of thyroid nodules. Molecular analysis of the mutation status of B-RAF in thyroid nodule FNAs may provide guidance for treatment planning.

Study Design: Cross-sectional study.

Subjects and Methods: A retrospective chart review was undertaken for clinically relevant data of papillary thyroid cancer (PTC), follicular variant of PTC (FV-PTC), and nonmalignant goiters. After blinded pathologic review, histologic and cytologic samples were analyzed by LightCycler PCR (LCPCR) with allele-specific fluorescent probe melting curve analysis (FMCA) for the V600E mutation of B-RAF.

Results: Of the 45 patient samples analyzed, B-RAF mutation was found to be significantly higher in papillary carcinomas when compared to follicular variant of papillary thyroid carcinomas (55.6% vs 14.3%, P = 0.05). Pathologic B-RAF mutational status significantly correlated with cytologic B-RAF mutational status ( P < 0.0001), cytologic interpretation ( P = 0.012), and histologic diagnosis ( P = 0.011).

Conclusions: Determination of B-RAF V600E mutation of thyroid nodule FNAs by LCPCR may be a useful tool to guide treatment planning. These data support investigating the utility of this molecular marker in a prospective manner.

Reporting thyroid fine-needle aspiration: Literature review and a proposal

Reporting schemes for thyroid fine-needle aspirations in the literature were reviewed and classified according to the number of categories in the scheme and the significance of each category. The sensitivity, specificity, and positive predictive and negative values were determined for each scheme, if possible. A reporting scheme based on the probability of finding carcinoma on histology is proposed.

Benign follicular thyroid lesions versus follicular variant of papillary carcinoma: differentiation by architectural pattern

Differentiation between benign and malignant follicular lesions is one of the difficult diagnostic areas in thyroid fine needle aspiration (FNA). Nuclear criteria are usually used to distinguish between them. In this study the microarchitectural pattern of common benign follicular lesions, namely nodular hyperplasia (NH) and follicular adenoma (FA) were analysed in comparison with those of follicular variant of papillary carcinoma (FVPC) in order to aid in their differentiation. The FNA smears of histologically proven cases of FVPC, NH and FA were reviewed and compared. The microarchitectural features of FVPC, NH and FA were described. Three cytological features--multi-layered rosettes, branching monolayered sheets and balls of thick pinkish colloid--were exclusively observed in FVPC. Hyperplastic papillae with intact follicles and colloid were frequently seen in NH, 83% and 100%, respectively. Albeit less frequently, they were also noted in FVPC, 25% and 75% of cases, respectively. These overlapping features make the distinction between FVPC and NH sometimes difficult; however, assessing the smears for the specific features of FVPC may help in their differentiation. None of the aforementioned microscopic findings with the exception of the seldom presence of colloid were documented in FA. The crowded clusters of follicular cells were seen both in FA and FVPC; however, they were complex and branching in the latter and round to oval in the former. Finally, smears with good recovery of material are indispensable for the identification of these helpful microarchitectural patterns.

The role of FNA in the initial management of thyroid lesions: 7-year experience in a district general hospital

Fine needle aspiration (FNA) cytology plays a major role in the diagnosis of the thyroid lesions in university hospitals and tertiary referral institutions. Our aim was to find out if this was possible in small district hospitals with limited resources. Over a 7-year period, from October 1994 to April 2002, 303 patients with thyroid swellings underwent FNA with an overall adequacy rate of 97.7%. FNAs were performed specifically by the pathologists, so that our inadequacy rate, 2.3% was far lower than 11-29% reported elsewhere. The FNA findings were compared with subsequent histology results in 67 cases. The diagnosis of benign and neoplastic lesions was predicted accurately by FNA in 93% and 94.7% of cases, respectively. The latter reached 100% if results of FNA in follicular neoplasms were excluded. Sensitivity and specificity were 85.6% and 97.6%, respectively, which is comparable with results from tertiary institutions. The commonest thyroid lesions in our hospital were nodular goitre (52.4%), followed by thyroiditis (17.6%) and neoplasia (13.9%). We conclude that, with the availability of appropriate personnel, FNA is feasible as the major modality in district general hospitals. FNA in follicular lesions remains challenging but could be overcome in part by recognizing the criteria to differentiate follicular variant of papillary carcinoma and other follicular proliferations. Aspiration, smearing, staining and interpretation should be left to pathologists or other well-trained personnel to ensure good quality and consistency.