Thyroid incidentalomas.

Thyroid nodules are very common. Most of them are benign non-secerning incidentally found nodules - thyroid incidentalomas. Ultrasound (US) is an essential initial diagnostic tool in thyroid nodules management. Based on the US character, thyroid nodules should be classified to one of the US risk categories (TIRADS - Thyroid Imaging Reporting and Data System). Based on the US risk category and size, some nodules should be referred to fine needle aspiration with cytological evaluation of the sample (FNAC), some should be followed just by US, and some require no follow-up. Further management depends on the FNAC (Bethesda category) and US risk category. In most nodules (Bethesda category II, repeatedly Bethesda category I, some of the nodules of Bethesda category III), just defensive management is recommended (US and/or clinical follow-up, or no follow-up). Usually, only few cases require diagnostic (Bethesda categories III, IV and V) or therapeutic (Bethesda V and VI) surgery. In decision-making of management of nodules Bethesda category III and V, molecular testing for mutations associated with thyroid cancer and serum calcitonin could be useful.

Review of a single institution's fine needle aspiration results for thyroid nodules: Initial observations and lessons for the future.

OBJECTIVE: Our objective was to evaluate the disease spectrum of thyroid cytopathology and correlation of the Bethesda reporting system with final histopathology in our medical centre. METHODS: This retrospective study was conducted from histopathology reports from Galilee Medical Center between August 2013 and September 2017. RESULTS: A total of 287 thyroid fine needle aspirations were included in the study. The majority (55.1%) of these were benign (B2). Surgery was performed on 53 cases and the total malignancy rate was 39.6%. Our study had a favourable accuracy rate of 70%. A B4 Bethesda category had a higher malignancy rate (50%) than previously reported. CONCLUSION: We found a higher malignancy rate (50%) based on the Bethesda B4 category of the fine needle aspirations in our series, yet it is based on a small sample. The differences in malignancy rates between centres have an important impact on clinical decisions.

High Serum Thyrotropin Concentrations within the Reference Range: A Predictor of Malignancy in Nodular Thyroid Disease.

OBJECTIVE: This study assessed whether or not a simple biochemical parameter, serum thyrotropin (TSH), within the reference range can predict the likelihood of thyroid malignancy in subjects undergoing fine-needle aspiration biopsy (FNAB) for thyroid nodules. SUBJECTS AND METHODS: This cross-sectional study evaluated 236 patients without overt thyroid dysfunction who were not on levothyroxine therapy. They underwent FNAB of the thyroid nodules at the Clementino Fraga Filho University Hospital between 2011 and 2012. The reference range and serum TSH quartiles were determined according to age-specific values for serum TSH and then compared between the cases with benign thyroid nodular disease and differentiated thyroid carcinoma (DTC) based on surgical pathology reports. RESULTS: Of the 236 patients, 201 (85.1%) underwent a surgical procedure (thyroidectomy) and 89/236 (44.3%) had DTC. The mean TSH concentrations were 2.09 ± 1.15 mU/L in benign patients versus 2.73 ± 1.33 mU/L in cases of DTC (p < 0.01). As TSH increased from quartiles 1 to 4, the frequency of a malignant diagnosis also increased progressively from 22% in quartile 1 to 65% in the last quartile (p ≤ 0.001). CONCLUSION: Thyrotropin levels were positively associated with the diagnosis of DTC in thyroid nodules.

Thyroid nodules classified as atypia or follicular lesions of undetermined significance deserve further research: Analysis of 305 surgically confirmed nodules.

OBJECTIVE: The objective of the present study was to determine the malignancy risk for nodules categorised as atypia or follicular lesions of undetermined significance atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) and to investigate the predictors of malignancy. METHODS: All nodules diagnosed as AUS/FLUS on fine needle aspiration (FNAs) performed between January 2011 and December 2015 were retrospectively reviewed. Clinical data, ultrasonographic features, follow-up data and the final pathological results were recorded. After further exclusion, only nodules that underwent surgical excision were included in the final analysis. The malignancy rate and the range of malignancy rates were calculated. Clinical and ultrasound features were examined to determine the predictors of malignancy. RESULTS: During the study period, FNA was performed on 9938 nodules, and 1019 (10.2%) nodules were diagnosed as AUS/FLUS. After further exclusion, 976 nodules were evaluated. After the initial diagnosis of AUS/FLUS, 139 (14.2%) patients underwent surgery, 518 (53.1%) had repeated FNAs. A total of 305 (31%) had undergone surgical excision at different time points. For surgically confirmed nodules, the malignancy rate after the initial FNA was 34.5% (the lower and upper thresholds for the malignancy rate were 19.3% and 66.3%, respectively), and 37.9% after the repeated FNA. No ultrasound feature was determined as a predictor, whereas age (>55 years) was a predictor for malignancy. CONCLUSIONS: The overall malignancy rate for nodules diagnosed as AUS/FLUS and the malignancy rate for nodules that underwent repeated FNA after AUS/FLUS were higher than the expected malignancy rates of the National Cancer Institute. It is, therefore, suggested that the current recommendations should be reconsidered.

The contemporary utility of intraoperative frozen sections in thyroid surgery.

PURPOSE: To determine the accuracy of intraoperative frozen section analysis on thyroidectomy specimens stratified by the Bethesda classification scheme and its utility for intraoperative decision-making. STUDY DESIGN: Retrospective chart review. METHODS: A retrospective review was performed on all patients who underwent thyroidectomy or thyroid lobectomy with intraoperative frozen sections at a tertiary care academic center from 2009 to 2015. RESULTS: There were 74 total patients who underwent partial or total thyroidectomy with intraoperative frozen section analysis of a thyroid nodule whom had previously undergone a thyroid fine needle aspiration of the nodule. The sensitivity, specificity, positive predictive value, and negative predictive value for a thyroid frozen section with respect to its prediction for malignancy was 81%, 95%, 98%, and 66%, respectively, with a diagnostic accuracy of 85%. For 37 patients with an indeterminate cytologic diagnosis on fine needle aspiration (Bethesda categories III-V), the sensitivity, specificity, positive predictive value, and negative predictive value for a thyroid frozen section was 81%, 91%, 95%, and 67%, respectively, with a diagnostic accuracy of 84%. False positives and false negatives resulted in 1 completion thyroidectomy for benign pathology and 3 reoperations for malignancy not discovered on frozen section. CONCLUSION: While intraoperative frozen sections on thyroid specimens may be helpful if positive, the false negative rate remains high. There appears to be limited value in routine frozen sections to guide clinical management and decision-making in the era of the Bethesda system.

[Management of patients with thyroid nodules: American Thyroid Association guidelines in the setting of Czech Republic]. / Diagnostika a dalsí péce o pacienty s tyreoidálními uzly: doporucení American Thyroid Association 2015 modifikované pro podmínky Ceské republiky.

Thyroid nodules are common finding. Most of them are of benign origin without thyroid dysfunction. Diagnosis is based on evaluation of thyroid function by assessment of serum thyroid stimulating hormone, and ultrasound for the purpose to identify the nodules which should be referred to fine needle aspiration biopsy (FNAB). The nodule size, ultrasound pattern and clinical risk factors should be considered before the FNAB is performed. The FNAB results should be categorized based on the risk of malignancy to improving a standardization of the patients management and minimizing number of false negative and false positive FNAB results. The most appropriate categorizing system seems to be Bethesda classification, although it is not completely optimal mainly because of controversial Bethesda III category.

Thyroid FNA cytology: Impact of the COVID-19 pandemic and vaccination in a Brazilian series.

BACKGROUND: The coronavirus disease 2019 pandemic prompted changes in medical practice, with a reduction in cytopathology volumes and a relative increase in the malignancy rate during lockdown and the initial postlockdown period. To date, no study has evaluated the impact of these changes on the volume of rapid on-site evaluation (ROSE) or on the frequency of cases according to The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) categories after vaccination. METHODS: Ultrasound-guided thyroid fine-needle aspiration (FNA) and ROSE assessments performed from January 2019 to May 2022 were evaluated retrospectively according to TBSRTC categories for three periods: prepandemic (period 1), from transmission to expansion (period 2), and after vaccination (period 3). RESULTS: There were 7531 nodules from 5815 patients. FNA cases increased throughout the pandemic despite a drop during lockdown. The frequency of TBSRTC categories changed. Nondiagnostic cases had an increase of 18.1% in period 2 and 76.2% after vaccination compared with prepandemic levels. Malignant cases increased from 2.3% to 4.2% in period 2 and to 5.1% in period 3, representing increases of 83.1% and 121.2%, respectively, compared with period 1. Data corrected by time showed increases in categories IV, V, and VI and a decrease in benign nodules during the two pandemic periods. ROSE was performed in 787 cases during the prepandemic period, and there were decreases of 29.4% and 22.8% in periods 2 and 3, respectively. The ROSE-to-category I ratio was reduced significantly after vaccination. CONCLUSIONS: Increased volume with sustained lower benign rates and higher malignant rates before and after vaccination indicate better selection of patients for FNA. A worse adequacy rate was correlated with a decrease in the number of ROSE assessments.

Diagnostic accuracy of Afirma gene expression classifier, Afirma gene sequencing classifier, ThyroSeq v2 and ThyroSeq v3 for indeterminate (Bethesda III and IV) thyroid nodules: a meta-analysis.

Objective: The management of thyroid nodules with indeterminate cytology (ITN) is still a challenge. To evaluate the performance of commercial molecular tests for ITN, we performed this comprehensive meta-analysis. Methods: We performed an electronic search using PubMed/Medline, Embase, and the Cochrane Library. Studies assessing the diagnostic accuracy of Afirma gene expression classifier (GEC), Afirma gene sequencing classifier (GSC), ThyroSeq v2 (TSv2), or ThyroSeq v3 (TSv3) in patients with ITN (only Bethesda category III or IV) were selected; Statistical analyses were performed by using Stata. Results: Seventy-one samples (GEC, n = 38; GSC, n = 16; TSv2, n = 9; TSv3, n = 8) in 53 studies, involving 6490 fine needle aspirations (FNAs) with ITN cytology with molecular diagnostics (GEC, GSC, TSv2, or TSv3), were included in the study. The meta-analysis showed the following pooled estimates: sensitivity 0.95 (95% CI: 0.94-0.97), specificity 0.35 (0.28-0.43), positive likelihood ratio (LR+) 1.5 (1.3-1.6), and negative likelihood ratio (LR-) 0.13 (0.09-0.19), with the best performance for TSv3 (area under the ROC curve 0.95 (0.93-0.96), followed by TSv2 (0.90 (0.87-0.92)), GSC (0.86 (0.82-0.88)), and GEC (0.82 (0.78-0.85)); the best rule-out property was observed for GSC (LR-, 0.07 (0.02-0.19)), followed by TSv3 (0.11 (0.05-0.24)) and GEC (0.16 (0.10-0.28), and the best rule-in was observed for TSv2 (LR+, 2,9 (1.4-4.6)), followed by GSC (1.9 (1.6-2.4)). A meta-regression analysis revealed that study design, Bethesda category, and type of molecular test were independent factors. Conclusion: We showed that in patients with ITN, TSv3 has the best molecular diagnostic performance, followed by TSv2, GSC, and GEC. As regards rule-out malignancy, GSC, and rule-in, TSV2 is superior to other tests.

Molecular Genetics Augment Cytopathologic Evaluation and Surgical Planning of Pediatric Thyroid Nodules.

PURPOSE: Molecular genetic testing in conjunction with cytopathology may improve prediction of malignancy in thyroid nodules, particularly those with indeterminate cytology (Bethesda III/IV). Though now commonplace in adults, pediatric data are limited. This study examines molecular genetics of pediatric nodules with correlation to cytologic and histologic classification at time of surgery and the distribution of mutations. METHODS: Retrospective chart review of 164 patients <22 years who underwent surgical resection of a thyroid nodule between 2002 and 2020 with molecular testing on fine-needle aspiration biopsy (FNA) or final histopathology. RESULTS: 85 (52 %) of 164 patients undergoing thyroid resection had available molecular genetic testing. BRAF V600E testing was performed on the FNA samples of 73 (86 %) patients and on 15 (18 %) surgical specimens; 31 (37 %) were positive. Of the remaining 54 patients, 21 had additional mutation/fusion testing. In 17 (81 %) cases, an alternate mutation/fusion was identified including 8 gene fusions, 3 DICER1 mutations, 4 NRAS mutations, one BRAF variant, and one unknown variant. BRAF, DICER1 mutations, and gene fusions predicted malignancy. Greater than 95 % of BRAF mutations were in Bethesda V/VI lesions and associated with classic variant PTC whereas fusions and DICER1 mutations clustered in Bethesda IV nodules. Bethesda III nodules harbored BRAF and NRAS mutations. In Bethesda IV nodules, a gene fusion or DICER mutation altered the surgical decision-making (upfront thyroidectomy rather than lobectomy) in 70 % of nodules submitted for genetic testing. CONCLUSION: Expanded molecular genetic testing on FNA of pediatric thyroid nodules, particularly Bethesda III/IV, may improve prediction of malignancy and augment surgical decision-making. LEVEL OF EVIDENCE: III.

Comparison of Fine-Needle Aspiration Cytopathology with Histopathological Examination of the Thyroid Gland in Patients Undergoing Elective Thyroid Surgery: Do We Still Need Fine-Needle Aspiration Cytopathology?

BACKGROUND: The thyroid gland is responsible for various functions, but it is susceptible to pathologies. The gold standard for preliminarily diagnosing thyroid abnormalities is fine-needle aspiration cytology (FNAC), although it has some limitations; thus, postoperative histopathological examination confirms the diagnosis. The aim of the present study was to compare preoperative FNAC results with postoperative histopathological examination. METHODS: This study is a retrospective study based on FNAC and postoperative histopathology examination, which were compared and analyzed. RESULTS: This study included 344 patients between 18 and 86 years old (mean age: 53.06 ± 13.89), comprising 274 females and 70 males (mean ages 52.72 ± 13.86 and 54.39 ± 14.05, respectively) with a 3.9:1 female-to-male ratio. Statistical significance between the FNAC and histopathology results was observed (p = 0.0000), and 86 (25.00%) patients were found to have been diagnosed incorrectly based on FNAC. The sensitivity of FNAC was 92.31%, and its specificity was 82.08%, with positive and negative predictive values of 68.57% and 96.08%, respectively. CONCLUSIONS: Due to many factors, FNAC may lead to over- or under-diagnosis, increasing the chances of complications associated with the selected treatment. However, we do not have any other more accurate tools; therefore, FNAC should still remain as the gold standard of preliminary examination.

Prevalence of malignancy in thyroid nodules with AUS cytopathology: A retrospective cross-sectional study.

Background: Category III (AUS; Atypia of Undetermined Significance) of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) was established to describe thyroid nodule features that are neither benign nor cancerous. Objectives: This study aims to evaluate the rate of thyroid malignancy in patients diagnosed with AUS at the Armed Forces Hospital Southern Region (AFHSR), Saudi Arabia. Method: The patients (508) diagnosed with AUS in their thyroid nodules underwent fine-needle aspiration cytology (FNAC). Data were collected through a chart-based approach, reviewing patients' medical records and relevant information. Results: Among the cases, the majority were females (84.6%). Among the different age groups, individuals between 40 and 50 years had the highest prevalence of thyroid nodules (32.5%). Approximately 27% of patients exhibited tumor sizes larger than 4 cm. FNAC results revealed 16.5% benign, 26% AUS, and 22.4% follicular neoplasm cases. Histopathology indicated 54.1% of benign and 37.2% of malignant cases. Papillary carcinoma accounts for 80.4% of all malignant cases. A significant correlation was observed between FNAC and postoperative histopathology (P value < 0.05). Hypoechoic nodules exhibited 33.9% of malignant cases, and calcification was observed in 25% of the cases. A significant association was found between malignancy and echogenicity and between malignancy and calcification (P value = 0.003 and 0.001, respectively). Conclusion: The findings of this study identify malignancy in thyroid nodules with AUS cytopathology, particularly in the Southern region of Saudi Arabia. The correlation between pre-surgery FNAC and postoperative histopathology supports FNAC's diagnostic value. Additionally, echogenicity and calcification can potentially contribute to predicting nodule malignancy.

The Incidence of Thyroid Cancer in Bethesda III Thyroid Nodules: A Retrospective Analysis at a Single Endocrine Surgery Center.

BACKGROUND: Fine-needle aspiration cytology (FNAC) is widely used to diagnose and monitor thyroid nodules. The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) is the standard for interpreting FNAC specimens. The risk of malignancy in Bethesda III nodules, also known as Atypia of Undetermined Significance (AUS), varies significantly throughout several studies published worldwide. This retrospective study examines the risk of cancer in thyroid FNAC categorized as Bethesda III as identified in the final histopathology of thyroidectomy specimens at a single endocrine surgery center. METHODS: This retrospective cohort analysis included 1038 consecutive patients who underwent elective thyroid surgery with complete follow-up data between January 2020 and March 2024. Preoperative data on clinical and pathological characteristics have been collected. The final histopathology report from the thyroidectomy specimen was compared to the results of the preoperative FNAC on nodules that were judged to be Bethesda category III. Statistical methods were performed using SPSS version 29. RESULTS: A total of 670 ultrasound-guided FNACs (64.5%) performed during the study period were included in the final analysis. The study population was predominantly female, represented by 79.6% of patients with a mean age of 42.5 (SD 12.1), while 20.4% were male and significantly older with mean age of 45.13 years (p = 0.02). The FNAC inadequacy rate was 5.1%, which was associated with a high risk of malignancy (6 out of 34; 17.6%). Out of the total sample size of 170 patients classified as group III, 57 were found to have malignancies in final surgical histopathology, representing 33.5% of the cases within this category. The secondary gender-related outcome analysis showed that female patients classified under the Bethesda II category had a significantly higher risk of malignancy, with a rate of 21.2%, compared to males who had a malignancy rate of 3.4% in the same Bethesda category (p = 0.001, chi-square test). However, the female patients exhibited prognostically superior non-invasive tumors compared to male individuals (p = 0.02, chi-square test). CONCLUSION: This study's results indicate that Bethesda categories II and III are associated with a higher risk of malignancy in comparison to the reports of the first and third editions of the TBSRTC, particularly for female patients classified under category II.

Follow-up of atypia and follicular lesions of undetermined significance in thyroid fine needle aspiration cytology.

OBJECTIVE: To report our experience of atypia of undetermined significance (AUS)/follicular lesion of undetermined significance (FLUS) rate and outcome. METHODS: Among 7658 patients with 19 569 nodules, 524 (2.7%) nodules were diagnosed as AUS/FLUS on fine needle aspiration (FNA). After exclusion of patients with simultaneous nodules that were suspicious for follicular neoplasm or malignancy or that were malignant, 368 (4.8%) patients were diagnosed as AUS/FLUS. The outcome of 146 patients who had undergone surgery or repeated fine needle aspirate at the time of preparation of this study was evaluated. The original FNAs were matched to repeated FNAs and thyroidectomy or diagnostic lobectomy specimens. RESULTS: Seventy-two (19.6%) of the 368 patients had directly undergone surgery, either a lobectomy or a thyroidectomy: of these, 27 (37.5%) had neoplastic nodules (21 were malignant). Seventy-four (20.1%) of the 368 patients had repeat FNA. On second FNA, 47 of 74 (63.5%) were benign, three were suspicious for follicular neoplasm, one was malignant and 23 (31.1%) were non-diagnostic. Four patients had a third FNA: two were AUS/FLUS, one was malignant and one non-diagnostic. One patient had a fourth FNA, which was diagnosed as AUS/FLUS. Sixteen (21.6%) of 74 patients with repeat FNA had surgery: three of these had neoplastic nodules (two were malignant). Overall, 88 of the 368 (23.9%) patients had a thyroidectomy of which 30 (34.1%) were neoplastic and 23 (26.1%) malignant. The neoplastic rate for patients who were once diagnosed with AUS/FLUS was 8.2% and the malignancy rate 6.3%. The malignancy rate for patients on follow-up at the time we prepared the study was 15.7% (23/146); 222 remained on follow-up without surgery or repeat FNA or were managed elsewhere. CONCLUSIONS: Although in this category repeat FNA is expected rather than excision, we suggest evaluation of all AUS/FLUS patients in multidisciplinary meetings to decide management and recommend follow-up of all patients with this diagnosis.

The Role of Frozen Section Examination in Thyroid Surgery.

In endocrine pathology, frozen section (FS) examination is most commonly used for the intraoperative evaluation of thyroid and parathyroid tumors, as well as cervical lymph nodes. In the past, frozen section was considered a fundamental tool in thyroid surgery. However, with advancements in preoperative ultrasound and fine-needle aspiration biopsy (FNAB), there have been increasing queries about its routine use due to the improved preoperative diagnosis. Nowadays, while the use of FS during thyroidectomy has decreased, it is still used as an additional method for different purposes intraoperatively. FS may not always provide definitive results. If FS will alter the surgical plan or extent, it should be applied. Routine FS is not recommended for evaluating thyroid nodules. But in addition to FNAB, if FS results may change the operation plan or extent, they can be utilized. FS should not be applied for thyroid lesions smaller than 1 cm, and the entire lesion should not be frozen for FS. For the assessment of thyroid nodules, the use of FS is recommended based on the Bethesda categories of FNAB. In Bethesda I category nodules, FS may contribute to distinguishing between malignant and benign lesions and guide surgical treatment. In Bethesda II nodules, where the malignancy rate is low, the performance of FNAB and FS can be compared, but it's not recommended due to the lack of a significant contribution to the surgical strategy. The sensitivity of FS in Bethesda III and IV nodules is low; its contribution to the diagnosis is limited, and it does not provide an apparent benefit to treatment; therefore, it is not recommended. In Bethesda V nodules, FS can effectively confirm the malignancy diagnosis, contribute to the surgical strategy, and reduce the possibility of completion thyroidectomy, and accordingly, it is recommended for use. Nonetheless, in Bethesda V nodules with a benign FS report, the malignancy rate remains high, so it should not be used to rule out malignancy. In Bethesda VI nodules, the performance of FS is lower or comparable to FNAB and does not significantly contribute to the treatment strategy; hence, it is not recommended. Particularly in patients with papillary thyroid cancer, intraoperative FS can be effective in detecting extrathyroidal extension and can assist the surgeon in determining the extent of thyroid surgery and central neck dissection. FS has high sensitivity and specificity in evaluating the lymphatic status of the central region intraoperatively and can be used to determine the extent of central compartment node dissection. During thyroidectomy, FS examination can be used in recognizing parathyroid tissue and distinguishing it from fatty tissue, thymus, thyroid, lymph nodes, especially in differentiating metastatic lymph nodes.

TSH level as a risk factor of thyroid malignancy for nodules in euthyroid patients.

Objective: With the increased prevalence of incidental thyroid cancer, determining the predictors of thyroid malignancy has become a source of debate. This study aimed to determine the impact of thyroid stimulating hormone (TSH) levels on rates of thyroid cancer in euthyroid patients. Methods: A retrospective study included 421 patients who underwent thyroidectomy at a tertiary hospital between 2016 and 2020. Patients' demographics, history of cancer, pre-operative workup and final histology reports were obtained. The study sample was divided into two groups based on the final histopathology (benign vs malignant). The two groups were compared using the appropriate statistical tests to determine the predictors of thyroid cancer in euthyroid patients. Results: TSH levels were significantly higher in patients with malignant nodules compared to those with benign nodules (1.94 vs 1.62, p = 0.002). It was 1.54 times more likely for thyroid nodules to be malignant when TSH levels were higher (p = 0.038). Meanwhile, larger nodules (> 4 cm) were significantly more prevalent in benign nodules (43.1%) than in malignant nodules (21.1%). Larger nodules decreased the possibility of thyroid cancer by 24% (OR = 0.760, p-value = 0.004). Conclusions: High TSH levels in euthyroid patients were significantly correlated with the risk of thyroid malignancy. In addition, as Bethesda category proceeded toward malignancy, TSH levels increased. High TSH levels and small nodule diameters can be used as additional parameters in predicting thyroid cancer in euthyroid patients.

Intraoperative frozen section performance for thyroid cancer diagnosis.

Objective: A primary medical relevance of thyroid nodules consists of excluding thyroid cancer, present in approximately 5% of all thyroid nodules. Fine-needle aspiration biopsy (FNAB) has a paramount role in distinguishing benign from malignant thyroid nodules due to its availability and diagnostic performance. Nevertheless, intraoperative frozen section (iFS) is still advocated as a valuable tool for surgery planning, especially for indeterminate nodules. Methods: To compare the FNAB and iFS performances in thyroid cancer diagnosis among nodules in Bethesda Categories (BC) I to VI. The performance of FNAB and iFS tests were calculated using final histopathology results as the gold standard. Results: In total, 316 patients were included in the analysis. Both FNAB and iFS data were available for 272 patients (86.1%). The overall malignancy rate was 30.4%% (n = 96). The FNAB sensitivity, specificity, and accuracy for benign (BC II) and malignant (BC V and VI) were 89.5%, 97.1%, and 94.1%, respectively. For all nodules evaluated, the iFS sensitivity, specificity, and accuracy were 80.9%, 100%, and 94.9%, respectively. For indeterminate nodules and follicular lesions (BC III and IV), the iFS sensitivity, specificity, and accuracy were 25%, 100%, and 88.7%, respectively. For BC I nodules, iFS had 95.2% of accuracy. Conclusion: Our results do not support routine iFS for indeterminate nodules or follicular neoplasms (BC III and IV) due to its low sensitivity. In these categories, iFS is not sufficiently accurate to guide the intraoperative management of thyroidectomies. iFS for BC I nodules could be an option and should be specifically investigated.

Diagnostic accuracy of fine needle aspiration biopsy versus postoperative histopathology for diagnosing thyroid malignancy.

INTRODUCTION: Ultrasound-guided fine needle aspiration biopsy (FNAB) is currently widely used for the initial screening of patients with thyroid nodules enabling prevention of unnecessary surgery. The purpose of this study was to retrospectively analyse the diagnostic accuracy of thyroid FNAB compared with postoperative histopathology of a large cohort from Azerbaijan. METHODS: We evaluated the FNAB results of 738 patients who underwent thyroid surgery at the National Centre of Oncology in Azerbaijan. The measures of diagnostic accuracy were calculated for the ultrasound-guided preoperative FNAB results (based on the six diagnostic categories of the Bethesda classification) compared with postoperative histopathologic results (benign or malignant) for correspondent areas. RESULTS: Considering both DC V and DC VI categories (387 cases) as 'cytologic-positive' and DC II category (72 cases) as 'cytologic-negative', we found 14 false-positive and 10 false-negative results. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy were 97.4%, 86.1%, 96.4%, 81.6% and 94.8%, respectively. Conversely, when considering only the DC VI category as 'cytologic-positive', the sensitivity, specificity, PPV, NPV and diagnostic accuracy of FNA were 93.2%, 100%, 100%, 81.6% and 97.1%, respectively. CONCLUSIONS: The results of our cohort demonstrated high levels of diagnostic accuracy, supporting FNAB's role as a reliable diagnostic tool in the preoperative evaluation of thyroid nodules. The sensitivity, specificity, NPV, PPV and accuracy of thyroid FNAB in our institution were comparable with those of other institutions.

Cancer rate of Bethesda category II thyroid nodules.

Aim Thyroid nodules are very common and may be found in more than 50% of the population. Fine-needle aspiration cytology (FNAC) of thyroid nodules is a very useful diagnostic tool with high sensitivity and predictive value for diagnosis. The Bethesda System for Reporting Thyroid Cytopathology (BSRTC) uses six categories for thyroid cytology reporting (I-nondiagnostic, IIbenign, III-atypia of undetermined significance (AUS)/ follicular lesion of undetermined significance (FLUS), IV-follicular neoplasm/suspicious for follicular neoplasm (SFN), V-suspicious for malignancy, and VI-malignant. Our objective was to determine the malignancy rate in Bethesda II nodules. Methods From June 2010 to May 2020 a retrospective analysis was performed among 1166 patients who underwent thyroid surgery for benign thyroid diseases in our institution. Thyroid cytopathological slides and Ultrasound (US) reports were reviewed and classified according to the BSRTC. Data collected included age, gender, cytological features, and histological type of thyroid cancer. Results During the study period, 44.77% (522/1166) of patients with an FNA categorized as Bethesda II underwent thyroid surgery. Incidental malignancy was found in 1.53% (8/522) cases of Bethesda II. The most common malignant tumour type was papillary thyroid carcinoma. Conclusion The current study demonstrates that incidental thyroid carcinoma can be diagnosed after thyroidectomy even in patients with an FNA categorized as Bethesda II.

Comparison of Conventional Smear and Liquid-Based Cytology in Adequacy of Thyroid Fine-Needle Aspiration Biopsies without an Accompanying Cytopathologist.

Objectives: In this study, we aimed to compare the adequacy of conventional smear (CS) and liquid-based cytology (LBC) methods in thyroid fine-needle aspiration biopsy (FNAB) samples obtained without an accompanying cytopathologist during the procedure. Furthermore, we aimed to investigate the presence of a significant difference between the rates of nodules classified as Bethesda Category III and malignancy in both techniques and the features of the nodules affecting malignancy. Methods: A total of 625 nodules from 572 patients who were found suitable for biopsy were included in this retrospective study. FNABs were performed by interventional radiologists without an accompanying cytopathologist during the procedures. The specimens were either prepared using CS or LBC preparation methods. Cytopathological diagnostic adequacy and cytopathological results of the specimens were evaluated according to Bethesda category, and the relationship between the morphological findings was evaluated retrospectively. Results: Of all the biopsy preparations, 338 (54.1%) of them were transferred to pathology in liquid-based solution and 287 (45.9%) were transferred as CS. Malignancy rates of the biopsy samples were found similar in both LBC and CS methods. Considering the nodules classified as Bethesda Category II, III, IV, V, and VI, there was no statistical difference between the results of both methods. Non-diagnostic biopsy rate was higher in the specimens prepared by CS method (p<0.001). Conclusion: In this study, the adequacy rate of FNAB was found significantly higher in LBC method compared to the CS method. LBC was more practical and faster than the CS method. We think that LBC method may be preferred in FNAB of thyroid nodules.

Patient outcomes following surgical management of thyroid nodules classified as Bethesda category III (AUS/FLUS).

INTRODUCTION: The Bethesda classification system for reporting thyroid cytopathology is the standard for interpreting fine needle aspirate (FNA). Because of its heterogeneity and inconsistent reporting, atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS), known as Bethesda category III, is the most controversial category. Thyroid nodules that fall within Bethesda categories III-IV have an overall risk of malignancy of between 15 and 40%. The aim of this study was to determine the malignancy rate in Bethesda III nodules. MATERIAL AND METHODS: A retrospective study was performed for 1166 patients who underwent thyroid surgery for multinodular goitre (MNG) or solitary nodular goitre (SNG) in our institution between June 2010 and May 2020. Data retrieved included demographic characteristics of the patients, FNB cytology, thyroid function test results, type of thyroidectomy, and final histology results. RESULTS: During the study period, 29.5% (344/1166) of patients with an FNA categorized as AUS/FLUS underwent thyroid surgery. Of these 344 patients, 190 were diagnosed with MNG and 154 with SNG. Incidental malignancy was found in 35 of 190 cases of MNG (18.42%) and 31 of 154 cases of SNG (20.13%). The most common malignant tumour type in either category was the follicular variant of papillary thyroid carcinoma. CONCLUSIONS: The current study demonstrates that patients with a FNA categorized as AUS/FLUS may have a higher risk of malignancy than traditionally believed. Reconsideration may be necessary to guidelines that recommend observation or repeat FNA in this category of patients.