Histopathological Review of Diagnostic Categories of the Bethesda System for Reporting Thyroid Cytopathology - An Institutional Experience of 5 Years

Hemithyroidectomy, does the indication influence the outcome?

PURPOSE

Hemithyroidectomies are mainly performed for two indications, either therapeutically to relieve compression symptoms or diagnostically for suspicious nodule(s). In case of the latter, one could consider the approach to be rather extensive since the majority of patients have no symptoms and will have benign disease. The aim of this study is to investigate the complication rates of diagnostic hemithyroidectomy and to compare it with the complication rates of compressive symptoms hemithyroidectomy.

METHODS

Data from patients who had undergone hemithyroidectomy either for compression symptoms or for excluding malignancy were extracted from a well-established Scandinavian quality register (SQRTPA). The following complications were analyzed: bleedings, wound infections, and paresis of the recurrent laryngeal nerve (RLN). Risk factors for these complications were examined by univariable and multivariable logistic regression.

RESULTS

A total of 9677 patients were included, 3871 (40%) underwent surgery to exclude malignancy and 5806 (60%) due to compression symptoms. In the multivariable analysis, the totally excised thyroid weight was an independent risk factor for bleeding. Permanent (6-12 months after the operation) RLN paresis were less common in the excluding malignancy group (p = 0.03).

CONCLUSION

A range of factors interfere and contribute to bleeding, wound infections, and RLN paresis after hemithyroidectomy. In this observational study based on a Scandinavian quality register, the indication "excluding malignancy" for hemithyroidectomy is associated with less permanent RLN paresis than the indication "compression symptoms." Thus, patients undergoing diagnostic hemithyroidectomy can be reassured that this procedure is a safe surgical procedure and does not entail an unjustified risk.

Correlation of ultrasound-based TIRADS and the Bethesda system for reporting of thyroid cytopathology: A study in a tertiary care centre

BACKGROUND

The age-standardised incidence rate of thyroid cancer in India is 1 in 416 in the general population. This increased incidence has mainly been attributed to improved detection methods for small thyroid lesions. Two such methods are the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TIRADS) and the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC).

AIMS AND OBJECTIVES

To study the correlation between ACR TIRADS and TBSRTC, and between each system and the final histopathological report.

MATERIALS AND METHODS

Thyroid cytopathology cases were retrieved for the period January 2019 to July 2022. For each case, the TIRADS score and Bethesda category were noted. Histopathology specimens were also traced.

RESULTS

The study comprised 1100 cases, with 955 female and 145 male patients (M:F = 1:6.59), and ages ranging between 7 and 85 years. The TIRADS scoring was available for 1036 cases. Histopathology was available for 231 cases. There was a significant correlation between TIRADS and TBSRTC, with a p-value of 0.000 and a substantial Kappa agreement of 0.688. Both TIRADS and TBSRTC also had significant correlations with the histopathology data, with a p-value of 0.000 for each. The sensitivity values for TBSRTC and TIRADS were 69.4% and 65.8%; specificity, 99.3% and 96.5%; positive predictive value (PPV), 98.3% and 91.8%; and negative predictive value (NPV) 84.7% and 84.4%, respectively. The risk of malignancy (ROM) was also calculated and was found to be high, especially for TBSRTC II, III, IV and V (11.3%, 20%, 61.5%, 97.4% respectively) and TIRADS 2 and 3 (10.3% and 29.6% respectively).

CONCLUSION

The TIRADS and TBSRTC systems of categorisation of thyroid lesions are concordant and could help improve the overall survival rate of patients with thyroid malignancies.

Nitric oxide, thyroglobulin, and calcitonin: unraveling the nature of thyroid nodules

Background

Thyroid nodules (TN) are localized morphological changes in the thyroid gland and can be benign or malignant.

Objective

The present study investigates the relationships between biochemical markers in serum (s) and their homologs in washout (w) after fine-needle aspiration biopsy (FNAB) of the TN of interest and their correlation with cytology specimen findings.

Methods

We investigated the relationships between serum biochemical markers nitric oxide (NO), thyroglobulin (TG), and calcitonin (CT), their homologs in washout after FNAB of the TN of interest, and cytology findings of biopsy samples classified according to the Bethesda system for thyroid cytopathology in this study, which included 86 subjects.

Results

Washout TG (TGw) level positively correlates with the cytology finding of the biopsy. A higher level of TGw correlates with higher categories of the Bethesda classification and indicates a higher malignant potential. The levels of serum NO (NOs), serum TG (TGs), serum CT (CTs), and washout CT (CTw) do not correlate with the cytology finding of the biopsy, and the higher levels of washout NO (NOw) correspond to the more suspicious ultrasound findings.

Conclusion

The findings of our study suggest that TGw and NOw could be used as potential predictors of malignancy in TN.

Incidence and Malignancy Rates in Thyroid Nodules in North-East Indian Population by Bethesda System: A Single Institutional Experience of 3 Years

Suvamoy ChakrabortyIntroduction  Goiter is one of the most common conditions encountered clinically (up to 60% of population) with thyroid malignancy being one of the most common endocrine malignancies. The American Thyroid Association has advocated the need for validation of the Bethesda system of fine needle aspiration cytology (FNAC) in each center. The risk of malignancy (ROM) for Bethesda categories in the Indian population is limited. Objective  As there are variations in the effectiveness of FNAC, this study aims to study the role of FNAC in evaluating thyroid nodules, estimating the risk of malignancy in thyroid nodules in the North-East Indian population, and correlating the FNAC findings with HPE (histopathological examination). Materials and Methods  A total of 110 patients with thyroid nodules had visited the Department of Otorhinolaryngology during 2017-2020. Case records were retrieved, out of which only 66 patients had both FNAC and HPE reports. The FNAC of 66 patients were studied. Statistical Analysis  Data were analyzed using STATA V14. Fischer's exact test was used to determine the association of Bethesda system in diagnosing thyroid malignancy. The percentage agreement between the FNAC and HPE was calculated using the Kappa statistics. The diagnostic validity of FNAC in the diagnosis of malignant thyroid nodule was reported. Results  The sensitivity, specificity, PPV, and NPV of FNAC in diagnosing thyroid malignancy were 52%, 94.3%, 89%, and 69% respectively. The risk of malignancy (ROM) for Bethesda I to VI categories in our study was 20%, 25%, 67%, 40%, 78%, and 100% respectively ( p -value < 0.001, Fischer's exact test). Conclusion  A specificity of 94.3% and PPV of 89% of FNAC makes it a good reliable tool in ruling in malignancy in our population. The higher ROM in indeterminate categories necessitates the need to consider thyroidectomy with or without intraoperative frozen section analysis in our population. Similar higher ROM has been reported in a few other Indian studies. These findings may suggest an increased ROM for Bethesda categories III and IV in the Indian population; however, the statement needs further validation from large multicentric studies with research to find the reason for the increased risk.

The diversities in thyroid cytopathology practices among Asian countries using the Bethesda system for reporting thyroid cytopathology

Background

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) has been adopted and widely used among Asian countries. This study aims to investigate the application of TBSRTC in thyroid cytology practice among Asian countries.

Methods

We searched electronic databases including PubMed and Web of Science from 2010 to 2019. Meta-analysis of proportion and their 95% confidence intervals (CIs) were calculated using the random-effect model. Meta-regression and subgroup analysis were used to search for heterogeneity origins.

Results

We included 42 Asian studies with 84.953 fine-needle aspirations. Among six categories, benign was the most commonly diagnosed category. The resection rate (RR) and risk of malignancy (ROM) were highest in malignant and SM categories, and lowest among benign nodules. Thyroid cytology practice in Asia was characterized by a low RR and high ROM in patients with indeterminate thyroid nodules. There was a significant amount of heterogeneities of TBSRTC outputs (frequency, resection rate, and malignancy risk) among Asian countries. Meta-regression showed that the sources of heterogeneity might stem from the differences in study origin and the application of molecular testing. We highlighted the usefulness of preoperative molecular testing to select patients for surgery.

Conclusions

Our study provided insight regarding thyroid cytology practice among Asian countries. Active surveillance is commonly used in Asian practice resulting in a low RR and high ROM for indeterminate nodules. There are still variations in general thyroid cytology practice in Asia. Future guidelines and consensus regarding the application of TBSRTC in thyroid cytology practice among Asian countries are required.