Long-term assessment of a multidisciplinary approach to thyroid nodule diagnostic evaluation

Clinical study on the relationship between the incidence of complications and tumour size after thermal ablation of benign thyroid nodules

OBJECTIVE

The present study aimed to analyze the relationship between the incidence of complications and tumor size following thermal ablation of benign thyroid nodules (BTNs).

METHODS

In this retrospective study, 1198 patients who underwent thermal ablation for unifocal BTN were enrolled. Receiver Operating Characteristic analysis was performed to select the cutoff values of the maximum diameter (MD) for dividing patients into different groups or subgroups. Multivariable logistic regression was performed to identify the risk factors. Propensity score matching (PSM) was employed to control for confounding variables.

RESULTS

The overall complication rate was 3.8% (45/1198). Major complications included hoarseness (2.4%), nodule rupture (0.3%) and delayed hemorrhage (0.1%), whereas minor complications were limited to intraoperative hemorrhage (0.9%). The difference in the overall complication rate between the smaller group (< 3.15 cm) and the larger group (> 3.15 cm) was significant (1.0% vs. 6.5%, p < 0.001). In the subgroup analysis, a significant difference was observed between the 3.15-4.15 cm and > 4.15 cm subgroups (4.2% vs. 8.7%, p = 0.023); however, no significant difference was identified between the < 2.35 and 2.35-3.15 cm subgroups (0.6% vs. 1.6%, p = 0.390). Multivariable logistic regression indicated that MD and the nodule component were associated with complications. After PSM, no significant difference in complication rates was observed between MWA and RFA in either the smaller group (p = 1.000) or the larger group (p = 0.186).

CONCLUSIONS

The incidence of complications in thermal ablation is greater for larger thyroid nodules, particularly for predominantly solid nodules with MDs greater than 3.15 cm.

Cytopathology of follicular and oncocytic follicular thyroid neoplasms: A Bethesda System perspective

The third edition of The Bethesda System for Reporting Thyroid Cytopathology includes category IV, follicular neoplasm (FN), which is used to classify fine-needle aspirates of thyroid nodules that may correspond to invasive follicular-derived neoplasia other than papillary thyroid carcinoma. This diagnosis is infrequently rendered, and may represent a challenge for pathologists. This review presents a practical approach to FN and its subtype oncocytic follicular neoplasm (OFN). First, minimal criteria for the diagnosis must be achieved, namely sufficient cellularity, architectural features consistent with neoplasia, and follicular cell or oncocytic cytomorphology. Second, select diagnoses that are common or important differential diagnoses for FN or OFN must be ruled out, via a combination of morphological findings and limited ancillary tests, when available. These include follicular nodular disease, parathyroid sampling, metastatic carcinoma, noninvasive follicular thyroid neoplasm with papillary-like nuclear features, medullary thyroid carcinoma, certain subtypes of papillary thyroid carcinoma, and lymphocytic thyroiditis. This approach should allow for a careful selection of cases where diagnostic thyroid lobectomy is an appropriate therapeutic modality.

Emerging Potential of Metabolomics in Thyroid Cancer-A Comprehensive Review

Thyroid cancer is a very common endocrine system malignancy. Nevertheless, a dearth of precise markers makes it challenging to apply precision medicine to thyroid cancer. The limitations of standard diagnosis techniques (fine-needle aspiration biopsy), such as indeterminate cases and inaccuracies in distinguishing between different types of cancers, lead to unnecessary surgeries and thus warrant the development of more discriminatory biomarkers to improve the accuracy of existing diagnostic and prognostic techniques. Moreover, individualized therapies for thyroid cancer are necessary to avoid overtreatment of indolent lesions and undertreatment of high-risk progressive disease. As thyroid cancer metabolic signatures are associated with disease aggressiveness and responsiveness to therapy, metabolomics has been recently used for diagnostic and prognostic biomarker discovery. This strategy has enabled the detection of several metabolites from tissue samples or biofluids to facilitate the classification of disease aggressiveness and to potentially assist in individualized therapies. In this review, we summarize the utilization and potential of metabolomics in thyroid cancer.

High Rates of Unnecessary Surgery for Indeterminate Thyroid Nodules in the Absence of Molecular Test and the Cost-Effectiveness of Utilizing Molecular Test in an Asian Population: A Decision Analysis

Objectives: Cytologically indeterminate thyroid nodules (Bethesda class III or IV) carry a 10-40% risk of malignancy. Diagnostic lobectomies are frequently performed but negative surgeries incur unnecessary costs on the healthcare system, potential complications, and negative impacts on quality of life. Molecular tests (MTs) have been developed to reduce unnecessary surgeries. However, well-validated, high-performance MTs are often expensive, and their cost-effectiveness has not been studied in the Asian population. This study evaluates the rate of unnecessary surgery in the setting without MT (our current practice) and the cost-effectiveness of introducing a commercially available MT for the management of cytologically indeterminate thyroid nodules in a modernized city in Asia. Methods: Management decisions and outcomes of consecutive Bethesda III or IV thyroid nodules in a tertiary endocrine surgery center in Hong Kong were evaluated. Costs of health service provided by the public health system, which covers >90% of healthcare service in the city, were retrieved. A decision tree model was developed to compare the cost-effectiveness in avoiding unnecessary surgeries of current practice versus routine MT from a public healthcare provider's perspective. In our current practice, MT was not available, and patients with indeterminate nodules received either upfront lobectomy, repeat fine needle aspiration cytology (FNAC), or active surveillance. Results: Over a 4-year period, 2157 FNACs were performed. After exclusion, 1957 FNACs were analyzed, and 18.6% were Bethesda III or IV. Thirty-six percent of these cytologically indeterminate nodules received upfront surgery, with 28% having malignancy in final pathology, that is, 72% of surgeries were unnecessary. Routine MT could reduce 82 unnecessary surgeries/year, 26% more than current practice. Routine MT resulted in an incremental cost-effectiveness ratio of Hong Kong dollar (HKD) 49,102 (US dollar [USD] 6314) per unnecessary surgery. Sensitivity analysis showed test cost of MT contributed significantly to incremental cost-effectiveness ratio. Lowering the commercial price of MT to below HKD 8044 (USD 1031) would render routine MT cost-saving. Conclusion: Currently, a high rate of unnecessary surgeries is being performed for cytologically indeterminate thyroid nodules. MT was more effective in reducing unnecessary surgeries than current practice, but at a higher cost. MT will become cost-saving if the test cost could be lowered.

Avoidable biopsies? Validating artificial intelligence-based decision support software in indeterminate thyroid nodules

BACKGROUND

Multiple artificial intelligence (AI) systems have been approved to risk-stratify thyroid nodules through sonographic characterization. We sought to validate the ability of one such AI system, Koios DS (Koios Medical, Chicago, IL), to aid in improving risk stratification of indeterminate thyroid nodules.

METHODS

A retrospective single-institution dataset was compiled of 28 cytologically indeterminate thyroid nodules having undergone molecular testing and surgical resection, with surgical pathology categorized as malignant or benign. Nodules were retrospectively evaluated with Koios DS. After nodule selection, automated and AI-adapter-derived Thyroid Imaging Reporting and Data System (TI-RADS) levels were recorded, and agreement with radiologist-derived levels was assessed using Cohen's κ statistic. The performance of malignancy classification was compared between the radiologist and AI-adapter. Biopsy thresholds were re-evaluated using the AI-adapter.

RESULTS

In this cohort, 7 (25%) nodules were malignant on surgical pathology. The median nodule size was 2.4 cm (interquartile range: 1.8-2.9 cm). Median radiologist and automated TI-RADS levels were both 4, with κ 0.25 ("fair agreement"). Malignancy classification by the radiologist provided sensitivity 100%, specificity 33.3%, positive predictive value (PPV) 33.3%, and negative predictive value (NPV) 100%, compared with the AI-adapter's performance with sensitivity 85.7%, specificity 76.2%, PPV 54.5%, and NPV 94.1%. Using the AI-adapter, 14 of 28 biopsies would have been deferred, 13 of which were surgically benign.

CONCLUSION

Koios automated and radiologist-derived TI-RADS levels were in consistent agreement for indeterminate thyroid nodules. Malignancy reclassification with the AI-adapter improved PPV at minimal cost to NPV. Risk stratification with the addition of the AI-adapter may allow for more accurate patient counseling and the avoidance of biopsies in select cases that would otherwise be cytologically indeterminate.

Fate of nondiagnostic thyroid fine needle aspirations

BACKGROUND

Thyroid nodules may be detected during the workup of thyroid hormone abnormalities and as incidental findings during unrelated imaging studies. The diagnosis of a thyroid nodule is mainly established by performing fine needle aspiration (FNA) under ultrasound guidance. Thyroid nodules are classified as nondiagnostic, defined in the Bethesda System for Reporting Thyroid Cytopathology as samples with excess blood, cyst fluid only, and lack of thyroid follicular cells. The current study evaluates a series of nondiagnostic FNAs to assess whether repeat sampling improves yield and what patient management, and outcomes are after a nondiagnostic FNA.

METHODS

Thyroid FNAs from 2016 to 2023 were retrieved from our institution archives. All cases were performed under ultrasound guidance and with rapid on-site evaluation. Cases were assigned the Bethesda System Category. Nondiagnostic FNAs were further reviewed for repeat FNA procedures, potential molecular testing, or diagnostic resections.

RESULTS

In total 3104 thyroid FNAs were reviewed, with 153 (4.9%) being nondiagnostic. Of the 154 FNAs, there were 129 patients with an average age of 60 and a male-to-female ratio of 1:3.2. Of the 130 patients, there were 50 patients who underwent 55 repeat FNAs. Thirty-seven (67%) of the repeats were benign, 13 (24%) were nondiagnostic again, and 5 (9%) were atypia of undetermined significance (AUS). Molecular testing was performed on repeat FNAs diagnosed AUS. Four cases showed no mutations and had a high likelihood of being benign. One case did have an NRAS Q61R mutation, and resection revealed a noninvasive follicular thyroid neoplasm with papillary-like nuclear features. Seventeen (13% of all cases) with nondiagnostic FNA were resected. Twelve (71%) thyroidectomies showed benign adenomatous nodules. The remainder showed incidental papillary thyroid microcarcinoma (0.1 cm), an infarcted follicular adenoma, a noninvasive follicular thyroid neoplasm with papillary-like nuclear features, and metastatic renal cell carcinoma (2×).

CONCLUSION

Thyroid nodules with nondiagnostic cytology are reassuring of being highly likely a benign nodule. Only 5 of the 55 (9%) repeat FNAs yielded abnormalities, with only one of those being truly a follicular neoplasm (confirmed by molecular testing and resection). No primary thyroid malignancies have been identified in follow-up (repeat FNA or surgery). Clinical and ultrasound follow-up may be more appropriate management for nondiagnostic thyroid FNAs.

The sensitivity and specificity of fine needle aspiration cytology in detecting thyroid malignancy according to Bethesda system at a teaching hospital in Saudi Arabia

Background

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) aims to standardize the terminology and morphologic criteria associated with thyroid fine-needle aspiration cytology (FNAC) results while also providing corresponding risk assessments for malignancy. contributing to more consistent and standardized reporting of thyroid nodules and aiding clinicians in making informed decisions. Since then, it has been undergoing revisions and updates to further improve its utility and accuracy.

Materials and Methods

This is a retrospective study conducted at a tertiary care center. All patients with a history of thyroid gland swelling who had previously undergone FNA were included. The procedure included cytopathologists performing FNAC for all cases of midline neck swelling. Demographic and histopathology data were correlated with the cytological diagnosis.

Results

We included 288 cases. Of those, 234 (81.3%) were female and 54 (18.8%) were male. The presentation age range was 18-91 years. The most reported category was benign, which constituted 30.9% of the cases followed by malignancy (27.1%). As for thyroid lesions, papillary carcinoma was the most prevalent (43.6%). The correlation on cyto-histopathology was presented in every diagnostic category, showing high heterogeneity in diagnostic specificity and sensitivity. The overall diagnostic specificity and sensitivity were 56.05% (95% confidence interval [CI]: 47.92-63.95%) and 80.92% (95% CI: 73.13-87.25%), respectively. Positive and negative predictive values were 60.57% and 77.88%, respectively.

Conclusion

Our data suggests that the TBSRTC system promotes similar sensitivity and specificity to those reported elsewhere. It standardizes reporting and improves communication between cytopathologists and clinicians.

Pregnancy After Beating Thyroid Cancer: A Case Series

Thyroid cancer is common among women of reproductive age and is a frequently occurring cancer during pregnancy, following breast cancer. Contributing factors include radiation exposure, iodine deficiency, and genetic conditions like multiple endocrine neoplasia type 2 (MEN2). Pregnancy significantly impacts thyroid function, leading to gland enlargement and altered thyroid stimulating hormone (TSH) levels due to hormonal changes, including elevated human chorionic gonadotropin (hCG) and estrogen. When differentiated thyroid cancer (DTC), particularly papillary thyroid carcinoma (PTC), is diagnosed during pregnancy or shortly after, careful management is essential. Treatment usually involves total thyroidectomy, with radioactive iodine therapy delayed until after childbirth. A review of cases indicates that women with PTC can have successful pregnancies with close medical supervision. Despite the complexities of cancer treatment during pregnancy, outcomes for both mother and baby are generally positive. These cases emphasize the importance of a collaborative approach in managing thyroid cancer during pregnancy and highlight the need for further research to optimize treatment and outcomes for both mother and child.

Critical Appraisal of the 2017 Bethesda System for Reporting Thyroid Cytopathology with Cytohistological Concordance and Estimation of Risk of Malignancy - An Institutional Study

Aim

Bethesda System for reporting thyroid cytopathology established in 2009 was updated for the first time in 2017. Since its introduction very few studies have been done on the utility of recently introduced "The 2017 Bethesda System for Reporting Thyroid Cytopathology" (TBSRTC II) and estimation of risk of malignancy in various categories.

Material and methods

This was a prospective study done on thyroid lesions in which lesions were evaluated cytologically and classified according to TBSRTC II. Histopathological correlation was done, wherever possible. ROM was calculated for each Bethesda category in both ways as per TBSRTC II i.e. with NIFTP and excluding NIFTP from the malignant category.

Results

Using 2017 TBSRTC, 190 cases of thyroid FNACs were classified into 6 diagnostic categories. Cytohistological correlation was available in 60 cases. ROM was calculated which changed only in category III and V as only these two categories showed one case each of NIFTP. However there was an overestimation of ROM in category II and III as there are selection biases and not all thyroid nodules underwent surgical resections.

Conclusion

To conclude, the risk of malignancy calculated in two ways in the recent 2017 Bethesda system may have higher clinical relevance as those lesions with high ROM are defined for surgical excision. Thus we recommend that "The 2017 Bethesda system for Reporting Thyroid Cytopathology" should be implemented uniformly in our country as it provides a homogenous and standardised terminology resulting in better management of patients with thyroid nodular disease.

Indolent Behavior of Malignant Bethesda III Nodules Compared to Bethesda V/VI Nodules

BACKGROUND

The Bethesda system classifies all fine-needle aspiration specimens into 1 of 6 categories. We speculated that cancers within each Bethesda category would have distinct clinical behavior.

METHODS

This is a retrospective analysis of patients from a single academic medical center with a histologic diagnosis of thyroid cancer who had an initial diagnosis of Bethesda III, IV, V, or VI cytology.

RESULTS

A total of 556 cases were included, with 87 cases of Bethesda III, 109 cases of IV, 120 cases of V, and 240 cases of VI. Bethesda III showed similarities with V/VI compared to IV with a predominance of papillary thyroid cancer. The interval from diagnosis to surgery was longer in Bethesda III compared to Bethesda V/VI (median 78 vs 41 days, P < .001) (Fig. 1). Yet, patients with Bethesda III had a higher probability of achieving remission (62% vs 46%, P < .03), a lower possibility of recurrence (8% vs 24%, P < .001), and a shorter interval to achieve remission (median 1218 vs 1682 days, P = .02) compared to Bethesda V/VI, which did not change after adjusting for age, sex, radioactive iodine therapy, mode of surgery, and tumor size. More than 70% of Bethesda III that later presented with recurrence had T3/T4 disease or distant metastasis.

CONCLUSION

Cancers with Bethesda III cytology had a less aggressive clinical phenotype with better prognosis compared to V/VI despite histological similarities. The time to remission was shorter in Bethesda III despite a longer interval between diagnosis and surgery. The initial cytological diagnosis may guide management.

Molecular testing for thyroid nodules: Where are we now?

Approximately 25% of the fine needle aspiration samples (FNAB) of thyroid nodules are classified as "indeterminate samples", that means, Bethesda III and IV categories. Until the last decade, most of these cases underwent diagnostic surgery, although only a minority (13-34%) confirmed malignancy postoperatively. In view of this, with the objective of improving the preoperative diagnosis in these cases, the molecular tests emerged, which are validated from the diagnostic point of view, presenting good performance, with good diagnostic accuracy, being able to avoid diagnostic surgeries. With the advancement of knowledge of the role of each of the mutations and gene rearrangements in thyroid oncogenesis, molecular markers have left to play only a diagnostic role and have been gaining more and more space both in defining the prognostic role of the tumor, as well as in the indication of target therapy. Thus, the objective of this review is to show how to use the tool of molecular tests, now commercially available in the world, in the management of indeterminate cytological nodules, assessing the pre-test malignancy risk of the nodule, through clinical, ultrasonographic and cytological characteristics, and decide on the benefit of molecular testing for each patient. In addition, to discuss its new and promising prognostic and therapeutic role in thyroid cancer.

The role of primary cilia in thyroid diseases

Primary cilia (PC) are non-motile and microtube-based organelles protruding from the surface of almost all thyroid follicle cells. They maintain homeostasis in thyrocytes and loss of PC can result in diverse thyroid diseases. The dysfunction of structure and function of PC are found in many patients with common thyroid diseases. The alterations are associated with the cause, development, and recovery of the diseases and are regulated by PC-mediated signals. Restoring normal PC structure and function in thyrocytes is a promising therapeutic strategy to treat thyroid diseases. This review explores the function of PC in normal thyroid glands. It summarizes the pathology caused by PC alterations in thyroid cancer (TC), autoimmune thyroid diseases (AITD), hypothyroidism, and thyroid nodules (TN) to provide comprehensive references for further study.

Thyroid fine-needle aspiration cytology: malignancy rate in the category of indeterminate significant atypia/indeterminate significant follicular lesion

BACKGROUND

Fine needle aspiration cytology (FNAC) is a standard preoperative diagnostic modality for thyroid nodules. The Bethesda Thyroid Cytopathology Reporting System (TBSRTC) defines the FNAC atypia group as atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS).

OBJECTIVES

Determine the risk of malignancy after surgical resection in patients with AUS/FLUS.

DESIGN

Retrospective.

SETTING

Pathology department of a tertiary care center.

PATIENTS AND METHODS

All thyroid FNACs between 2015 and 2023 that were diagnosed as AUS/FLUS in Turkey. Patient demographics, preoperative ultrasonographic features, and follow-up data were collected.

MAIN OUTCOME MEASURES

Relationship between AUS/FLUS diagnosis and final histopathological diagnosis.

SAMPLE SIZE

562.

RESULTS

In total, 562 thyroid nodules were diagnosed as AUS/FLUS, and 267 (47.5%) were surgically excised. A malignant histopathological diagnosis was given in 28 cases (10.4%). Malignancy risk sensitivity of AUS/FLUS diagnosis was 75.68% (95% CI=58.80-88.23%), specificity was 55.24% (95% CI=50.91-59.52%), positive predictive value was 10.49% (95% CI=8.71-12.58%), and negative predictive value was 97.04% (95% CI=94.86-98.31%). In the ultrasonographic data, having symptomatic nodules, nodule calcification, and irregular nodule borders were all statistically significant signs of cancer in a one-variable analysis (P<.01). The presence of a family history emerged as a statistically significant prognostic marker for malignancy (P=.012). Although not statistically significant, the malignancy rate for nodules with nuclear atypia was 11.9%, significantly higher than the rate of 8.3% for nodules with architectural atypia only (P=0.32).

CONCLUSIONS

The diagnosis of AUS/FLUS has a high rate of predicting the risk of malignancy and should continue to be offered. In addition to cytopathological features, ultrasound data and family history should be taken into consideration when evaluating the case.

LIMITATIONS

Retrospective design and no molecular studies.

Core Needle Biopsy in the Diagnosis of Thyroid Nodules

BACKGROUND

Core needle biopsy (CNB) is a relatively new technique for the diagnosis of thyroid nodules, and there are currently no large clinical series available. CNB results from 3000 cases are presented in this article.

METHODS

A spring-loaded 20-gauge needle was used for CNB under local anesthesia and ultrasonography guidance for 3000 patients with nodular goiter (584 males, 2416 females, mean age: 48.5). One physician performed all biopsy procedures without conducting on-site pathological examinations.

RESULTS

There were non-diagnostic 22 (.7%), benign 2620 (87.4%), atypia of undetermined significance and/or, follicular lesion of undetermined significance 90 (3%), follicular neoplasms and/or suspicious for follicular neoplasm 53 (1.7%), suspicious for malignancy 160 (5.4%), and malignant 55 (1.8%) cases. The CNB procedure was repeated in 19 non-diagnostic cases, and 17 of these patients were benign and two had malignancy. Thyroidectomy was performed on patients who had malign CNB results. All final pathology reports, except for one, were malignant for the patients who had malignant CNB results. The specificity and the sensitivity of CNB were found to be 99.9% and 100%, respectively. There were no serious complications.

CONCLUSION

In thyroid nodules, core needle biopsy is a highly sensitive, specific, and reliable method that could be performed by a single physician. It does not require on-site pathological analysis and has a low incidence of complications and non-diagnostic rates.

Preoperative Evaluation of Thyroid Cancer: A Review of Current Best Practices

OBJECTIVE

The incidence of thyroid cancer has significantly increased in recent decades. Although most thyroid cancers are small and carry an excellent prognosis, a subset of patients present with advanced thyroid cancer, which is associated with increased rates of morbidity and mortality. The management of thyroid cancer requires a thoughtful individualized approach to optimize oncologic outcomes and minimize morbidity associated with treatment. Because endocrinologists usually play a key role in the initial diagnosis and evaluation of thyroid cancers, a thorough understanding of the critical components of the preoperative evaluation facilitates the development of a timely and comprehensive management plan. The following review outlines considerations in the preoperative evaluation of patients with thyroid cancer.

METHODS

A clinical review based on current literature was generated by a multidisciplinary author panel.

RESULTS

A review of considerations in the preoperative evaluation of thyroid cancer is provided. The topic areas include initial clinical evaluation, imaging modalities, cytologic evaluation, and the evolving role of mutational testing. Special considerations in the management of advanced thyroid cancer are discussed.

CONCLUSION

Thorough and thoughtful preoperative evaluation is critical for formulating an appropriate treatment strategy in the management of thyroid cancer.

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.

Identifying and Predicting Diverse Patterns of Benign Nodule Growth

CONTEXT

The natural history of benign thyroid nodules is typically characterized by slow growth and minimal risk of malignant transformation. Available data have, to date, been unable to elucidate the diversity of benign nodule growth patterns over time nor predictive of which patients follow which pattern.

OBJECTIVE

We aimed to better define the diverse patterns of benign nodule behavior and their predictors.

METHODS

We prospectively studied 389 consecutive patients with solitary, solid, cytologically benign thyroid nodules ≥1 cm and follow-up ultrasound for at least 4 years. Demographic, sonographic, biochemical data were collected at initial evaluation, and subsequent growth patterns were identified over the follow-up. Predictors of growth at initial evaluation and 3 years of follow-up were defined.

RESULTS

The mean (±SD) follow-up was 7.7 (±2.7) years. Three distinct growth patterns were identified: A) stagnant nodules with average growth rate < 0.2 mm/year; B) slow-growing nodules with a rate 0.2 to 1.0 mm/year; and C) fast-growing nodules increasing > 1.0 mm/year. Fast-growing nodules represented 17.2% of the cohort, and were more frequent in patients younger than 50 years (OR 2.2 [1.2-4.1], P = 0.016), and in larger nodules (2.0-2.9 cm, OR 3.5 [1.7-7.1], P = 0.001; >3.0 cm, OR 4.4 [1.8-10.4], P = 0.001 vs reference 1-1.9 cm). In a multiple regression model, nodule growth at 3 years at an average growth rate over 0.2 mm/year over 3 years since initial evaluation was an independent predictor of longer-term fast nodule growth, even after adjusting for age, biological sex, TSH level, and nodule size (P < 0.001).

CONCLUSION

The natural history of benign nodule growth is diverse, with over 80% of nodules demonstrating minimal to no growth long-term. Nearly 20% of cytologically benign nodules may exhibit a fast, continued growth pattern, which can be predicted by the 3-year growth rate pattern. These findings can help inform decision making for tailored benign nodule follow-up and monitoring.

Clinical Characteristics, Diagnostic Approach and Outcome of Thyroid Incidental Findings vs. Clinically Overt Thyroid Nodules: An Observational Single-Centre Study

Context: Thyroid nodules are common and can present as clinically overt nodules (visible, palpable or symptomatic nodules) and so-called incidentalomas (coincidental findings on imaging techniques). The majority are benign but recognizing clinically relevant nodules remains a challenge. Current Dutch guidelines recommend to refrain from additional diagnostic testing in incidentalomas other than FDG-PET-incidentalomas, unless there are suspicious clinical and/or sonographic features. However, there is no consensus on the further approach and no "real-life" data on the outcome of such an approach. Objective: To compare clinical characteristics, diagnostic approaches and clinical outcome between patients referred with thyroid incidentalomas and non-incidentalomas at one academic referral thyroid clinic. Methods: Clinical and demographical characteristics, diagnostic and therapeutic approaches and outcome were retrospectively obtained from the files of all patients newly referred because of thyroid incidentalomas or non-incidentalomas to our institution (between March 2011 and January 2017). Subsequently, the data were compared between both groups. Results: In total, 351 patients (64.3%) were referred because of non-incidentalomas and 195 (35.7%) because of incidentalomas. Incidentalomas were smaller (48.7% <2 cm) than non-incidentalomas (23.4% <2 cm). Furthermore, incidentalomas were less often symptomatic (15.9 vs. 42.7% p < 0.001). Fine-needle aspiration was performed in a similar percentage of the patients in the two groups (62.6% of incidentalomas vs. 69.8% in non-incidentaloma, p = 0.08). Significantly less malignancies were found among incidentalomas compared to non-incidentalomas (5.1% vs. 11.1%, p = 0.019). Moreover, significantly more malignancies occurred in PET-incidentalomas than non-PET-incidentalomas (11.8% vs. 2.8%, p = 0.023). In fact, the proportion of malignancies in PET-incidentalomas and non-incidentalomas was similar (11.8% vs. 11.1%, p = 0.895). Stability or decrease in size was observed in 96.5% of nodules receiving ultrasound follow-up. Conclusions: Patients with small asymptomatic thyroid incidentalomas represent an important proportion of the patients referred for additional diagnostic evaluation. The risk of malignancy in these patients is lower than in those with symptomatic palpable lesions, particularly in the patients with incidentalomas discovered on CT, MRI or US. Our findings support the current recommendations from the Dutch guidelines to not indiscriminately perform additional analysis and treatment on all incidentalomas, but prioritize this to FDG-PET-incidentalomas and clinically relevant non-PET-incidentalomas. Moreover, US features can further refine the selection of the patients who require immediate FNAC and/or surgery.

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

BACKGROUND

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

AIMS AND OBJECTIVES

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

METHODS AND MATERIAL

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

RESULTS

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

CONCLUSIONS

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

The national rate of malignancy among Bethesda III, IV, and V thyroid nodules is higher than expected: A NSQIP analysis

BACKGROUND

The Bethesda System for Reporting Thyroid Cytopathology was formalized in 2007 to stratify cytologic specimens based on their risk of malignancy. Several studies have reported significant variations between their institutional rate of malignancy compared to the Bethesda System for Reporting Thyroid Cytopathology. The objective of this study was to determine the national rate of malignancy for Bethesda III, Bethesda IV, and Bethesda V thyroid nodules.

METHODS

From 2016 to 2019, patients with preoperative thyroid cytopathology and pathology results in National Surgical Quality Improvement database were included. The rate of malignancy was compared to the median the Bethesda System for Reporting Thyroid Cytopathology 2017, and risk factors associated with malignancy were identified for Bethesda III, Bethesda IV, and Bethesda V specimens.

RESULTS

In total, 13,121 patients with preoperative cytopathology and postresection pathology were identified. The national rate of malignancy was significantly higher than the Bethesda System for Reporting Thyroid Cytopathology 2017 for Bethesda III (36.2% vs 12.0%, P < .01), Bethesda IV (36.7% vs 25.0%, P < .01), and Bethesda V (91.1% vs 52.5%, P < .01) specimens. Male sex was significantly associated with malignancy in Bethesda III, Bethesda IV, and Bethesda V nodules (Bethesda III, odds ratio: 1.20, [1.01-1.42]; Bethesda IV, odds ratio: 1.47, [1.27-1.71]; Bethesda V, odds ratio: 1.28, [1.03-1.58]). Younger age was associated with malignancy in Bethesda III patients under 55 (odds ratio: 1.23, [1.06-1.42]), Bethesda IV patients under 42 (odds ratio: 1.23, [1.06-1.43]), and Bethesda V patients aged less than 47 (odds ratio: 1.38, [1.15-1.67]).

CONCLUSIONS

This is the largest cohort study to describe the national rate of malignancy for Bethesda III, IV, and V specimens in the United States. These results reveal the national rate of malignancy is higher than the implied rate of malignancy reported to patients based on the Bethesda System for Reporting Thyroid Cytopathology. We recommend counseling patients regarding this increased rate of malignancy to set appropriate expectations after surgical intervention.

The Bethesda system for reporting thyroid fine needle aspirates: A study of 1763 patients; with histopathological correlations, in eastern India

BACKGROUND

Fine-needle aspiration cytology (FNAC) is an important test for triaging patients with thyroid nodules. The 2007 National Cancer Institute Thyroid Fine-Needle Aspiration State-of-the-Science Conference helped instigate the recent publication of The Bethesda System for Reporting Thyroid Cytopathology (TBS).

AIMS AND OBJECTIVES

Terminology and therefore the probability of malignancy vary between pathologists and institutions. The purpose of this study was to evaluate a single institution's experience to determine if sub-classification (neoplasm versus lesion) aids in identifying patients at higher risk for malignancy. Also, an effort in regional and worldwide variation of significance of adoption of Bethesda classification has been evaluated.

MATERIALS AND METHODS

From 2018 to 2021, all patients with thyroid lesions' were evaluated for FNAC correlation with the surgical diagnosis. During this period, 1763 thyroid FNACs were reported. Histopathological examination (HPE) outcome data was available in 444 (25.2%) cases.

RESULTS

The cytologic-histologic diagnostic discrepancy rate was 11.5%. The sensitivity and specificity of thyroid FNA for the diagnosis of malignancy were 71.4% and 49.5%, respectively. In our study, the maximum cases were benign (84.5%). The malignancy risk for the different categories in our study, as seen by follow-up HPE, has corroborated well with the Bethesda System.

CONCLUSION

The current results indicated that FNAC provides an accurate diagnosis of thyroid malignancy. The classification is directly related to the risk of malignancy in each category and this helps in accurate clinical management of that category.

One hundred most-cited articles in head and neck surgery and analysis of female authorship

BACKGROUND

While female head and neck surgeons have made significant contributions to the field, women's achievements in scientific communication have traditionally been underreported.

METHODS

A search of high-impact journals in the field of head and neck surgery was performed in the Elsevier's Scopus database to identify the top 100 most-cited articles.

RESULTS

The top 100 most-cited articles (during the span of 1953 and 2016) had the highest total number of citations between 2005 and 2009. Women accounted for 36% of first authors and 25% of corresponding authors. Change in the relative number of first female authors in these top 100 articles did not increase significantly between 1950 and 2019.

CONCLUSION

The proportion of female first authors in head and neck surgery has not significantly increased over the past several decades, despite greater numbers of female trainees. Our findings support the need for additional research on female representation in head and neck surgery.

Follow-up of benign thyroid nodules confirmed by ultrasound-guided core needle biopsy after inconclusive cytology on fine-needle aspiration biopsy

PURPOSE

The goal of this study was to follow benign thyroid nodules confirmed by ultrasound (US)-guided core needle biopsy (CNB) after inconclusive cytology on fine-needle aspiration (FNA) biopsy.

METHODS

Sixty-two thyroid nodules from 62 patients with CNB-confirmed benign histology that initially had inconclusive cytology on FNA were retrospectively included. The thyroid nodules were followed for 38.7 months (median, 27.5 months; range, 6 to 101 months), and the US findings of biopsied nodules, such as the interval change in size, US characteristics, and imaging category based on the Korean Thyroid Imaging Reporting and Data System (K-TIRADS), were evaluated. In addition, patients' clinical records were reviewed for any further management or newly diagnosed thyroid malignancy.

RESULTS

Among 62 cases, three (4.8%) showed interval size growth, while 59 (95.2%) demonstrated no interval change or a decrease in size. There was no upgrade of K-TIRADS category or any newly diagnosed malignancy during the follow-up period.

CONCLUSION

US-guided CNB-confirmed benign thyroid nodules with inconclusive cytology on FNA showed a stable status during follow-up, and repeated CNB could be helpful in the management of nodules with inconclusive cytology on FNA.

A comparative study between conventional and the Bethesda System for Reporting Thyroid Cytology of 240 cases

Introduction

Thyroid nodule is a common disorder of thyroid. Despite their benign nature, they can be associated with multiple pathologic conditions including thyroid cancer. Fine-needle aspiration plays an essential role in evaluating thyroid nodules. The Bethesda System for Reporting Thyroid Cytology (TBSRTC) has attempted to standardize reporting and cytological criteria in aspiration smears.

Aim

The aim of this study is to compare the conventional and TBSRTC and to compare and correlate the cases with histological findings wherever available.

Materials and Methods

The present study was a retrospective study undertaken in the department of pathology from January 2018 to December 2018 to access the validity of TBSRTC considering histopathology as the gold standard. May Grünwald Giemsa and Papanicolaou stained thyroid FNA smears of 240 patients were collected which were reported by the conventional system for reporting thyroid cytology and also categorized as per current Bethesda nomenclature for thyroid cytology. Diagnosis of both the reporting systems was then compared and correlated with the histological diagnosis wherever possible.

Results

A total of 240 cases were examined on cytology, out of which histopathological correlation was possible in 110 cases. For benign thyroid lesions, sensitivity and specificity with conventional system were 69.91% and 40.25%, respectively, while with TBSRTC, sensitivity and specificity were 84.04% and 29.94%, respectively. Sensitivity and specificity of conventional system for malignant thyroid lesions were 58.56% and 69.91%, respectively, while with TBSRTC, sensitivity and specificity were 73.69% and 95.12%, respectively. The Bethesda system found to be highly sensitive for benign thyroid lesions and highly specific for malignant thyroid lesions as compared to the conventional method of reporting of thyroid cytology.

Conclusion

Bethesda system was found to be superior for reporting thyroid cytology over the conventional system of reporting for thyroid cytology.

Association of Fine-Needle Aspiration of Thyroid Nodules With Final Histopathology in Diagnosing Thyroid Malignancy: A Single Institute Retrospective Study

Background Fine needle aspiration cytology (FNAC) is the gold standard for detecting thyroid nodules. It is a cost-efficient approach that affords prompt and accurate evaluation. It is crucial in deciding to treat patients with suspected malignancy of thyroid nodules that might have thyroid surgery. According to findings in cytology, patients may be observed when the cytology is benign, and surgery can be performed if the cytology is malignant, which leads to a reduction in the incidence of unneeded surgery. Aim The current study aims to assess the concordance between FNAC of thyroid nodules with final histopathology and identify the different types of detected thyroid lesions. Methodology A retrospective record-based study reviewed the medical files of all patients presenting to the Armed Forces Hospital, Southern region, with suspected thyroid nodules from April 2018 to January 2020. Data were extracted using pre-structured data extraction sheet to avoid inconsistency. Data extracted included patients' demographic data, swelling laterality, size, ultrasound, and histopathological findings.  Results The baseline characteristics of studied samples in the present study: Forty-seven samples had a mean age of 44.27 (SD=±13.5) years, and 85.1% were female gender. The study showed that 12.5% of benign samples were lymphocytic in histopathology, 25% suspicious for follicular neoplasm samples were benign multi-nodular goiter in histopathology, and all 100% of samples suspicious for malignancy were malignant in final histopathology. Conclusions The current study showed that the malignancy rate of the examined nodules was not uncommon in FNAC and histopathology. Where papillary carcinoma was the most detected malignancy, the diagnosis of malignancy using FNAC is a cost-efficient approach that affords prompt and accurate evaluation. Once diagnosed, these cases should be subjected to surgery.

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.

Molecular Testing for Indeterminate Thyroid Nodules: Association of Negative Predictive Value With Nodule Size

BACKGROUND

Molecular testing helps stratify risk of malignancy in indeterminate thyroid nodules, but it may be limited in its ability to rule out malignancy in large nodules.

METHODS

We compared small thyroid nodules (<4 cm) to large thyroid nodules (4 cm or greater) in a retrospective, single center, cohort study of indeterminate thyroid nodules analyzed with ThyroSeq from 10/2015 through 4/2020. Our primary outcome was negative predictive value.

RESULTS

A total of 204 thyroid nodules were analyzed with ThyroSeq and 62 underwent resection allowing comparison to final pathology for 48 small nodules and 14 large nodules. A greater proportion of large nodules were observed in men (50.0% vs 18.8% in small nodules, P = .02), but median age was similar between the groups (49.0 vs 52.5 years, P = .95). False negative results comprised a higher proportion of tests for large nodules (14.3%) than small nodules (0%, P = .01). The negative predictive value of ThyroSeq in small nodules was 1 indicating a negative test reliably predicted a benign nodule, compared to .5 in large nodules indicating a negative test in this cohort was reliable in predicting benignity. Applying the same negative predictive value to the cohort of large nodules that did not undergo resection after negative molecular testing (n = 16), it is possible that 8 large thyroid malignancies were missed at our institution during the study period.

CONCLUSIONS

Large thyroid nodules are associated with a higher rate of false negative results and a lower negative predictive value during molecular analysis of indeterminate thyroid nodules.

Diagnostic utility of conventional and liquid-based cytology in the management of thyroid lesions; an institutional experience

Objectives:

Liquid-based cytology (LBC) is becoming a useful method in evaluating both gynecological and nongynecological preparations. Many studies have been conducted these days to see the quality of LBC in diagnosing thyroid lesions and its role is yet to be standardized. This study has been done to pick the cytomorphological features of thyroid lesions on LBC and to compare them with the conventional cytology of these lesions.The objective of the study is to evaluate the efficacy of thyroid fine-needle aspiration cytology processed by LBC as compared to conventional smears.

Material and Methods:

A prospective study has been done on 53 cases of thyroid lesions using standard conventional and LBC techniques.

Results:

In most of the cases, the cytological features are similar in conventional cytology smears and LBC, but the colloid film and the lymphocytic component show a clear picture on direct smears, whereas nuclear and cytoplasmic details are better evaluated in LBC slides. The preservative solution used in LBC could be efficiently used for the application of immunocytochemical and molecular techniques.

Conclusion:

LBC does not represent as a valid alternative to conventional cytology but it can be considered as a diagnostic utility process especially due to the possibility of applying additional techniques which enhance the efficacy of the cytological diagnosis of thyroid lesions.

Fine Needle Aspiration Cytology vs. Core Needle Biopsy for Thyroid Nodules: A Prospective, Experimental Study Using Surgical Specimen

PURPOSE

To evaluate and compare the diagnostic outcomes of ultrasonography (US)-guided fine needle aspiration (FNA) and core needle biopsy (CNB) performed on the same thyroid nodule using a surgical specimen for direct comparison.

MATERIALS AND METHODS

We included 89 thyroid nodules from 88 patients from February 2015 to January 2016. The inclusion criterion was thyroid nodules measuring ≥ 20 mm (mean size: 40.0 ± 15.3 mm). Immediately after surgical resection, FNA and subsequent CNB were performed on the surgical specimen under US guidance. FNA and CNB cytopathologic results on the specimen were compared with the surgical diagnosis.

RESULTS

Among the 89 nodules, 30 were malignant and 59 were benign. Significantly higher inconclusive rates were seen in FNA for malignant than benign nodules (80.0% vs. 39.0%, p < 0.001). For CNB, conclusive and inconclusive rates did not differ between benign and malignant nodules (p = 0.796). Higher inconclusive rates were seen for FNA among cancers regardless of US features, and in the subgroup of size ≥ 40 mm (62.5% vs. 22.9%, p = 0.028). Eleven cancers were diagnosed with CNB (36.7%, 11/30), while none was diagnosed using FNA.

CONCLUSION

In this experimental study using surgical specimens, CNB showed a potential to provide improved diagnostic sensitivity for thyroid cancer, especially when a conclusive diagnosis is limited with FNA.

Is Diagnostic Performance of Quantitative 2D-Shear Wave Elastography Optimal for Clinical Classification of Benign and Malignant Thyroid Nodules?: A Systematic Review and Meta-analysis

RATIONALE AND OBJECTIVE

This study is a dedicated 2D-shear wave elastography (2D-SWE) review aimed at systematically eliciting up-to-date evidence of its clinical value in differential diagnosis of benign and malignant thyroid nodules.

METHODS

PubMed, Web of Science, and Scopus databases were searched for studies assessing the diagnostic value of 2D-SWE for thyroid malignancy risk stratification published until December 2016. The retrieved titles and abstracts were screened and evaluated according to the predefined inclusion and exclusion criteria. Methodological quality of the studies was assessed using the Quality Assessment of Studies of Diagnostic Accuracy included in Systematic Review 2 (QUADAS-2) tool. Extracted 2D-SWE diagnostic performance data were meta-analyzed to assess the summary sensitivity, specificity, and area under the receiver operating characteristic curve.

RESULTS

After stepwise review, 14 studies in which 2D-SWE was used to evaluate 2851 thyroid nodules (1092 malignant, 1759 benign) from 2139 patients were selected for the current study. Study quality on QUADAS-2 assessment was moderate to high. The summary sensitivity, specificity and area under the receiver operating characteristic curve of 2D-SWE for differential diagnosis of benign and malignant thyroid nodules were 0.66 (95% confidence interval [CI]: 0.64-0.69), 0.78 (CI: 0.76-0.80), and 0.851 (Q* = 0.85), respectively. The pooled diagnostic odds ratio, negative likelihood ratio, and positive likelihood ratio were 12.73 (CI: 8.80-18.43), 0.31 (CI: 0.22-0.44), and 3.87 (CI: 2.83-5.29), respectively.

CONCLUSION

Diagnostic performance of quantitative 2D-SWE for malignancy risk stratification of thyroid nodules is suboptimal with mediocre sensitivity and specificity, contrary to earlier reports of excellence.

Subtype of atypia on cytology and risk of malignancy in pediatric thyroid nodules

BACKGROUND

Thyroid nodules with atypia of undetermined significance (AUS) are challenging to manage because of their intermediate risk of malignancy. Subclassification of atypia can refine malignancy risk in adult AUS nodules but has not been evaluated in children.

METHODS

This was a retrospective cohort study of pediatric patients (<19 years old) who underwent fine-needle aspiration (FNA) of a thyroid nodule with resulting AUS cytology. Atypia was subclassified as nuclear only, architectural only, nuclear and architectural, or oncocytic. The primary outcome was the association between atypia subtype and malignancy. A secondary outcome was the association of atypia subtype with repeat FNA cytology.

RESULTS

Sixty-eight AUS nodules in 61 patients were analyzed. The median age at FNA was 16.2 years (range, 9.8-18.9 years). Twenty-four nodules (35%) were malignant. Nuclear atypia only was present in 17 nodules (25%), architectural atypia only was present in 27 nodules (40%), nuclear and architectural atypia was present in 20 nodules (29%), and predominantly oncocytic features were present in 4 nodules (6%). The presence of nuclear atypia was associated with a significantly increased rate of malignancy (22 of 37 [59%] vs 2 of 31 [6.5%]; P < .001), whereas architectural atypia was not associated with malignancy (P = .8). Repeat FNA was performed in 42 of 68 nodules (62%). In nodules with initial nuclear and architectural atypia, benign repeat cytology had a high false-negative rate (3 of 6; 50%).

CONCLUSIONS

Pediatric AUS nodules with nuclear atypia have a high rate of malignancy, but architectural atypia is not associated with malignancy. In nodules with nuclear atypia, repeat FNA may inform clinical decisions regarding the need for resection. In the absence of suspicious clinical features, nodules without nuclear atypia might be considered for observation rather than resection or repeat FNA.

Testing of mutations on thyroid nodules with indeterminate cytology: A prospective study of 112 patients in Argentina

BACKGROUND

The study of genetic mutations in thyroid nodules makes it possible to improve the preoperative diagnosis of and reduce unnecessary surgeries on benign nodules. In this study, we analysed the impact of implementing a 7-gene mutation panel that enables mutations to be detected in BRAF and RAS (H/N/K) and the gene fusions PAX8/PPARG, RET/PTC1 and RET/PTC2, in a population in northern Argentina.

METHODS

We performed a prospective analysis of 112 fine needle aspirations diagnosed as having indeterminate cytology according to the Bethesda classification system. These include the Bethesda III or atypia of unknown significance/follicular lesion of unknown significance and Bethesda IV or follicular neoplasm/suspicious for follicular neoplasm categories. The mutations of the 7-gene panel were analysed and this information was linked to the available histology and ultrasound monitoring.

RESULTS

The BRAF V600E and RET/PTC1 mutations were associated with carcinoma in 100% of cases (n = 8), whereas only 37.5% (n = 3) of the nodules with RAS and 17% (n = 1) with PAX8/PPARG mutations were associated with carcinoma. From the histological diagnosis and ultrasound monitoring of patients, we can estimate that this panel has a sensitivity of 86% in detecting malignant carcinoma, a specificity of 77%, a positive predictive value (PPV) of 54% and a negative predictive value (NPV) of 94%. In this study, it was possible to reduce the number of surgeries by 48% in the patients analysed.

CONCLUSION

The implementation of the mutation panel allowed the appropriate surgical strategy to be selected for each patient, the number of two-step surgeries to be reduced, and active follow-up to be established in low-risk patients.

Approach to Bethesda system category III thyroid nodules according to US-risk stratification

This study evaluated how to manage Bethesda category III (Bethesda III) (atypia of undetermined significance/follicular lesion of undetermined significance [AUS/FLUS]) thyroid nodules according to the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) to reduce unnecessary surgeries. A total of 161 thyroid nodules diagnosed as Bethesda III underwent surgery from 2016 to 2019. Ultrasonography-guided fine-needle aspiration (US-FNA) or core needle biopsy (CNB) was used for repeat examination. K-TIRADS category was assigned to the thyroid nodules. The proportion of malignancy in Bethesda III nodules confirmed by surgery were significantly increased in proportion relative to K-TIRADS with 60.0% low suspicion, 88.2% intermediate suspicion, and 100% high suspicion nodules (p < 0.001). The proportion of malignancy in AUS and FLUS were significantly different (94.2% vs. 40.0% p = 0.003). The proportion of malignancy in AUS increased with K-TIRADS categories, but there was no difference in FLUS. All K-TIRADS high suspicion nodules were AUS as papillary carcinomas (99%), while 80% of FLUS nodules and 50% of follicular carcinomas showed K-TIRADS low suspicion. In 116 nodules with repeat FNA or CNB after initial Bethesda III results, the conclusive result rate was significantly increased in proportion to K-TIRADS with 58.3% low suspicion, 83.3% intermediate suspicion, and 88.8% high suspicion nodules (p = 0.015). K-TIRADS low suspicion nodules of Bethesda III nodules should be managed after risk-benefit consideration rather than immediate surgery or repeat examination. K-TIRADS for Bethesda III nodules can predict papillary carcinoma well, but not follicular carcinoma.

Performance of repeat cytology with reflex ThyroSeq genomic classifier for indeterminant thyroid cytology

BACKGROUND

The American Thyroid Association recommends either repeat fine-needle aspiration biopsy (FNAB) or molecular testing (eg, ThyroSeq) of Bethesda category III (atypia of undetermined significance/follicular lesion of undetermined significance [AUS/FLUS]) nodules to provide further risk stratification. How a testing algorithm that uses ancillary molecular tests performs as a reflex test for repeat sampling of indeterminant nodules remains unclear.

METHODS

Thyroid FNABs performed over a 24-month period that received a diagnosis of AUS/FLUS and underwent subsequent FNAB were analyzed.

RESULTS

In total, 187 patients were identified who received an FNAB diagnosis of AUS/FLUS and had repeat sampling. Of these patients, 64% received a subsequent indeterminant diagnosis on repeat biopsy: 7 (3.7%) repeat biopsies were diagnosed as nondiagnostic/unsatisfactory, 104 (55.6%) were diagnosed as AUS/FLUS, and 8 (4.3%) were diagnosed as follicular neoplasm/suspicious for follicular neoplasm. Of the repeat biopsied nodules, 63% underwent subsequent testing with ThyroSeq version 3. The diagnostic performance was calculated using only surgically confirmed nodules (sensitivity, 100%; specificity, 30%; positive predictive value, 41%; negative predictive value, 100%) and by assigning nonresected nodules with negative ThyroSeq or benign cytology results as benign (sensitivity, 100%; specificity, 88%; positive predictive value, 41%; negative predictive value, 100%).

CONCLUSIONS

In the majority of patients, repeat FNAB for AUS/FLUS did not preclude subsequent molecular ancillary testing because of the high rate of indeterminant results on repeat biopsy. The diagnostic performance of the testing algorithm reported here was very similar to other reports using either repeat biopsy or molecular testing alone. Ultimately, the algorithm of performing molecular testing on repeat indeterminant nodules increased the number of biopsies performed and lengthened the time to definitive risk stratification without a disproportionate decrease in the use of molecular testing or an appreciable improvement in diagnostic performance.

The value of ultrasound guided laser ablation in papillary thyroid recurrence carcinoma: A retrospective, single center study from China

OBJECTIVE

The efficacy and safety of ultrasound-guided percutaneous laser ablation (PLA) for treating recurrent papillary thyroid cancer nodules (RPTCNs).

METHODS

A retrospective study was conducted in 43 patients with single recurrent thyroid cancer which was diagnosed by fine needle aspiration biopsy (FNAB). The extent of ablation was assessed by contrast-enhanced ultrasound (CEUS) 24h after PLA. At baseline (before ablation), 6, and 12 months, and every 6 months thereafter, the following were recorded: nodule maximum diameter, volume reduction rate (VRR), complications, and side effects.

RESULT

All 43 patients were successfully treated with PLA without serious complications. All patients underwent CEUS 24 hours after PLA treatment, and all achieved complete ablation. The success rate of single ablation was 100%. The average follow-up time was 23.47 ± 6.50 months, 12 ~ 36 months. At the last follow-up, 32 (74.4%) ablation lesions disappeared completely and 11 (25.6%) ablation lesions showed scar-like changes. No lymph node metastasis was found during follow-up. The maximum diameter and volume of nodules decreased from 5.1 ± 1.4 mm, 86.22 ± 20.46 mm³ before operation to 0.73 ± 1.1 mm, 1.02 ± 1.92 mm³ at the end of observation (P < 0.01). The average volume reduction rates (VRR) at 6, 12, 18, 24, 30 and 36 months after ablation were 11.92%, 60.64%, 82.26%, 90.96%, 93.7% and 97.79% respectively. No regrowth of treated nodule and distant metastases were detected. One patient (2.3%) had local recurrence and was treated with PLA again.

CONCLUSION

Ultrasound-guided PLA appears to be effective and safe for treating unifocal RPTCNs in selected patients who are ineligible for surgery, which is suitable for clinical application and promotion.

A Rare Case of Systemic Sarcoidosis in a Middle-Aged Female with a Solitary Thyroid Nodule

Sarcoidosis is a multisystem inflammatory disease characterized by the presence of noncaseating granulomas. Sarcoidosis can affect any organ of the body, the lung being the most affected. Sarcoidosis rarely affects the thyroid gland, and only a few cases of thyroid-related sarcoidosis have been reported in the literature. Herein, we report a case of systemic sarcoidosis with multiple organ involvement in a patient with a solitary left thyroid nodule and benign Fine Needle Aspiration (FNA) findings. The patient was eventually diagnosed with thyroid sarcoidosis using a core needle biopsy of the thyroid nodule. With this case report, we highlight the limitations of the FNA. This case report has the objective to encourage clinicians to include thyroid sarcoidosis in the differential diagnosis of thyroid nodules in patients with systemic sarcoidosis even with unremarkable FNA findings.

Combination of ultrasound and molecular testing in malignancy risk estimate of Bethesda category IV thyroid nodules: results from a single-institution prospective study

PURPOSE

Malignancy prediction in indeterminate thyroid nodules is still challenging. We prospectively evaluated whether the combination of ultrasound (US) risk stratification and molecular testing improves the assessment of malignancy risk in Bethesda Category IV thyroid nodules.

METHODS

Ninety-one consecutively diagnosed Bethesda Category IV thyroid nodules were prospectively evaluated before surgery by both ACR- and EU-TIRADS US risk-stratification systems and by a further US-guided fine-needle aspiration cytology (FNAC) for the following molecular testing: BRAFV600E, N-RAS codons 12/13, N-RAS codon 61, H-RAS codons 12/13, H-RAS codon 61, K-RAS codons 12/13, and K-RAS codon 61 point-mutations, as well as PAX8/PPARγ, RET/PC1, and RET/PTC 3 rearrangements.

RESULTS

At histology, 37% of nodules were malignant. No significant association was found between malignancy and either EU- or ACR-TIRADS. In total, 58 somatic mutations were identified, including 3 BRAFV600E (5%), 5 N-RAS 12/13 (9%), 13 N-RAS 61 (22%), 7 H-RAS 12/13 (12%), 11 H-RAS 61 (19%), 6 K-RAS 12/13 (10%), 8 K-RAS 61 (14%) mutations and 2 RET/PTC1 (4%), 0 RET/PTC 3 (0%), 3 PAX8/PPARγ (5%) rearrangements. At least one somatic mutation was found in 28% and 44% of benign and malignant nodules, respectively, although malignancy was not statistically associated with the outcome of the mutational test. However, the combination of ACR-, but not EU-, TIRADS with the presence of at least one somatic mutation, was significantly associated with malignant histology (P = 0.03).

CONCLUSION

US risk stratification and FNAC molecular testing may synergistically contribute to improve malignancy risk estimate of Bethesda category IV thyroid nodules.

Evaluation of LMR, NLR and PLR as predictors of malignancy in indeterminate thyroid nodules

Objective

Thyroid nodules with indeterminate cytology represent 20% of all thyroid nodules. Inflammation plays an important role in cancer. Lymphocyte-to-monocyte ratio (LMR), neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are independent prognostic scores in numerous cancers, although no study has documented their role in cytology indeterminate nodules. The aim of this study is to evaluate the role of LMR, NLR and PLR values as predictors of malignancy in patients with cytology indeterminate nodules.

Methods

This retrospective study analysed data from 298 patients with indeterminate thyroid nodule. Anatomopathological and haematological data were analysed, dividing the population into two groups. LMR, NLR and PLR values were determined using ROC curve and data were analysed using independent samples t-test, test of proportions, Fisher’s exact test and univariate and multivariate logistic regression.

Results

We found that a baseline LMR value ≥ 4.09 was indicative of benignity of indeterminate nodule. The probability of malignancy in patients with LMR < 4.09 was 26 times higher than patients with a LMR value ≥ 4.09.

Conclusions

This study showed that only LMR has shown a concrete probability to find a thyroid cancer in patients with indeterminate nodules. Further studies are necessary to implement tailored treatment.

Noninvasive follicular thyroid neoplasm with papillary-like nuclear features and the risk of malignancy in thyroid cytology: Data from Singapore

INTRODUCTION

The impact of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) on the risk of malignancy (ROM) in fine-needle aspiration cytology (FNAC) per The Bethesda System for Reporting Thyroid Cytopathology has not been well reported in Singapore.

METHODS

We retrospectively identified 821 thyroid nodules with preoperative FNAC from 788 patients out of 1,279 consecutive thyroidectomies performed between January 2010 and August 2016 in a tertiary general hospital in Singapore. Possible cases of NIFTP were reviewed for reclassification and the impact of NIFTP on ROM was analysed.

RESULTS

The incidence of NIFTP was 1.2% (10 out of 821). If NIFTP is considered benign, ROM in Bethesda I through VI were 8.6%, 3.5%, 26.3%, 20.0%, 87.7%, 97.0% versus 8.6%, 4.2%, 28.1%, 26.7%, 89.2% and 100% if NIFTP is considered malignant. Eight patients with NIFTP had follow-up of 15 to 110 months. One had possible rib metastasis as evidenced by I131 uptake but remained free of structural or biochemical disease during a follow-up period of 110 months. None had lymph node metastasis at presentation, nor locoregional or distant recurrence.

CONCLUSION

Classifying NIFTP as benign decreased ROM in Bethesda II through VI, but the benignity of NIFTP requires more prospective studies to ascertain. The impact of NIFTP on ROM in our institution also appears to be lower than that reported in the Western studies.

Thyroid nodules >4 cm with atypia of undetermined significance cytology independently associate with malignant pathology

BACKGROUND

The risk of malignancy from nodules with atypia of undetermined significance cytology is estimated between 5% and 15%, though more recent studies suggest rates upwards of 48%. This study sought to characterize preoperative predictors of malignancy to aid in clinical decision-making.

METHODS

We performed a single institution retrospective review of all adult patients with unilateral thyroid nodules demonstrating atypia of undetermined significance cytology between March 1, 2013 and June 1, 2019 who underwent surgical resection (n = 266). Univariate and multivariate logistical analysis was performed using clinical and demographic variables to identify potential preoperative characteristics associated with malignant disease.

RESULTS

Malignancy was identified on final pathology in 24.7% of patients with atypia of undetermined significance cytology. Age, sex, exposure to ionizing radiation, family history of thyroid cancer, Hashimoto's disease, Afirma suspicious results, and smoking were not associated with malignancy on both univariate and multivariate analysis. Nodule size >4 cm was independently associated with malignancy risk on both univariate (odds ratio 2.44, 1.09-5.43, P < .03) and multivariate (odds ratio 2.96, 1.27-6.87, P < .02) analysis.

CONCLUSION

The results of this study demonstrate that nodules with atypia of undetermined significance cytology >4 cm are strongly associated with malignancy. We recommend strong consideration of surgery for all patients with thyroid nodules >4 cm and atypia of undetermined significance cytology.

Magnetic resonance imaging (MRI) radiomics of papillary thyroid cancer (PTC): a comparison of predictive performance of multiple classifiers modeling to identify cervical lymph node metastases before surgery

PURPOSE

To compare predictive efficiency of multiple classifiers modeling and establish a combined magnetic resonance imaging (MRI) radiomics model for identifying lymph node (LN) metastases of papillary thyroid cancer (PTC) preoperatively.

MATERIALS AND METHODS

A retrospective analysis based on the preoperative MRI scans of 109 PTC patients including 77 patients with LN metastases and 32 patients without metastases was conducted, and we divided enroll cases into trained group and validation group. Radiomics signatures were selected from fat-suppressed T2-weighted MRI images, and the optimal characteristics were confirmed by spearman correlation test, hypothesis testing and random forest methods, and then, eight predictive models were constructed by eight classifiers. The receiver operating characteristic (ROC) curves analysis were performed to demonstrate the effectiveness of the models.

RESULTS

The area under the curve (AUC) of ROC based on MRI texture diagnosed LN status by naked eye was 0.739 (sensitivity = 0.571, specificity = 0.906). Based on the 5 optimal signatures, the best AUC of MRI radiomics model by logistics regression classifier had a considerable prediction performance with AUCs 0.805 in trained group and 0.760 in validation group, respectively, and a combination of best radiomics model with visual diagnosis of MRI texture had a high AUC as 0.969 (sensitivity = 0.938, specificity = 1.000), suggesting combined model had a preferable diagnostic efficiency in evaluating LN metastases of PTC.

CONCLUSION

Our combined radiomics model with visual diagnosis could be a potentially effective strategy to preoperatively predict LN metastases in PTC patients before clinical intervention.

Thyroid diagnostic modalities (fine needle aspiration and core needle biopsy) with histology correlation: a tertiary centre experience

AIMS

To determine the proportion of thyroid fine needle aspiration (FNA) and core needle biopsy (CNB) cases reported at a single institute into each UK Royal College of Pathologists (RCPath) Thy1-5 and local T category, respectively. Where subsequent histology was available, malignancy rates, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy were compared for both procedures.

METHODS

1591 FNAs (2010-2018) and 514 CNBs (2013-2018) cases were identified, together with paired histology excision specimens.

RESULTS

The FNA samples were classified as: Thy1: 45.3%, Thy2/Thy2c: 22.1%, Thy3a/Thy3f: 28%, Thy4: 1.6% and Thy5: 3%; while the CNB were classified as: T1: 7.2%, T2: 22.4%, T3 59.3%, T4: 1% and T5: 10.1%. Comparison of FNA and CNB classified as Thy5/T5 showed a 100% risk of malignancy (ROM), sensitivity (98% vs 100%), specificity (14.1% vs 12.1%), PPV (29.4% vs 29.4%), NPV (94.9% vs 100%) and accuracy (36.5% vs 35.6%), respectively, for a diagnosis of malignancy. ROMs for other categories were: Thy1/T1 (9% vs 6.7%), Thy2/T2 (5.1% vs 0%), Thy3/T3 (17.5% vs 18.4%) and Thy4/T4 (73.3% vs 100%).

CONCLUSIONS

The proportion of cases in each RCPath Thy category has remained relatively stable during the 9-year study period, with the exception of the Thy3a category, which has increased over time. This finding is in line with other more recent reports in the literature and the proportion of T3 cases in the CNB group. The proportion of Thy2/Thy2c cases has also reduced over time, reflecting a local change in the triaging protocol for probable benign lesions. Both FNA and CNB showed comparable performance in our study.

False Negative Rates in Benign Thyroid Nodule Diagnosis: Machine Learning for Detecting Malignancy

BACKGROUND

Thyroid nodules are common; up to 67% of adults will show nodules on high-quality ultrasound, and 95% of these nodules are benign. FNA cytology is a crucial step in determining the risk of malignancy, and a false negative diagnosis at this stage delays cancer treatment. The purpose of this study is to develop a predictive model using machine learning which can identify false negative FNA results based on less-invasive clinical data.

MATERIALS AND METHODS

We conducted a retrospective medical record review at one academic and one community center. Inclusion criteria were thyroid nodules evaluated by ultrasound and FNA with a Bethesda II (benign) result or malignancy detected on pathology or FNA. Linear, non-linear, and ensemble models were generated with scikit-learn using 10-fold cross validation with repetition and compared with AUROC. The classification task was the prediction of malignancy using information acquired from less-invasive ultrasound and FNA.

RESULTS

A total of 604 subjects met inclusion criteria; 38 were diagnosed with malignancy. Of all algorithms tested, a Random Forest method achieved the best AUROC (0.64) in separating benign and malignant nodules, though the improvement over other tested algorithms was not statistically significant.

CONCLUSIONS

A Random Forest model performed better than random chance using readily available data obtained via standard evaluation of thyroid nodules. The diagnostic probability threshold of this model can be varied to minimize false positives at the cost of increasing the number of false negatives. Future studies will prospectively evaluate the model's performance.

The evolution of "atypia" in thyroid fine-needle aspiration specimens

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) provided a standardized framework for resulting thyroid fine-needle aspiration (FNA) specimens and introduced the low-risk category of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS). This indeterminate category has significantly evolved over time with the incorporation of molecular testing, reclassification of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), and a shift toward more conservative management. Despite these refinements, AUS/FLUS remains a challenge, at both the diagnostic and therapeutic level. We review the criteria for AUS/FLUS and the associated controversies in rendering this diagnosis, while highlighting the importance of a multidisciplinary approach to managing atypical thyroid nodules.