Thyroid nodules with Bethesda system III cytology: can ultrasonography guide the next step?

Differentiate Thyroid Follicular Adenoma from Carcinoma with Combined Ultrasound Radiomics Features and Clinical Ultrasound Features

Noninvasive differentiating thyroid follicular adenoma from carcinoma preoperatively is of great clinical value to decrease the risks resulted from excessive surgery for patients with follicular neoplasm. The purpose of this study is to investigate the accuracy of ultrasound radiomics features integrating with ultrasound features in the differentiation between thyroid follicular carcinoma and adenoma. A total of 129 patients diagnosed as thyroid follicular neoplasm with pathologically confirmed follicular adenoma and carcinoma were enrolled and analyzed retrospectively. Radiomics features were extracted from preoperative ultrasound images with manually contoured targets. Ultrasound features and clinical parameters were also obtained from electronic medical records. Radiomics signature, combined model integrating radiomics features, ultrasound features, and clinical parameters were constructed and validated to differentiate the follicular carcinoma from adenoma. A total of 23 optimal features were selected from 449 extracted radiomics features. Clinical and ultrasound parameters of sex (p = 0.003), interior structure (p = 0.035), edge (p = 0.02), platelets (p = 0.007), and creatinine (p = 0.001) were associated with the differentiation between benign and malignant follicular neoplasm. The values of area under curves (AUCs) of the radiomics signature, clinical model, and combined model were 0.772 (95% CI: 0.707-0.838), 0.792 (95% CI: 0.715-0.869), and 0.861 (95% CI: 0.775-0.909), respectively. A final corrected AUC of 0.844 was achieved for the combined model after internal validation. Radiomics features from ultrasound images combined with ultrasound features and clinical factors are feasible to differentiate thyroid follicular carcinoma from adenoma noninvasive before operation to decrease the unnecessary of diagnostic thyroidectomy for patients with benign follicular adenoma.

Optimization of the Management of Category III Thyroid Nodules Using Repeat FNA and TIRADS

The aim of the study was to examine the benefits of the joint use of repeat FNA (rFNA) and EU-TIRADS in category III nodules in relation to the kind of atypia: nuclear vs. architectural (denoted by AUS and FLUS respectively). The study included 127 AUS and 1739 FLUS nodules with a known category of EU-TIRADS. Repeat FNA was performed in 82 AUS and 934 FLUS nodules of which 57 and 515 were excised, respectively. AUS nodules had higher malignancy risk than FLUS nodules. EU-TIRADS showed higher accuracy for AUS nodules, the opposite to rFNA, that had higher accuracy for FLUS nodules. The combined criterion for AUS nodules (at least rFNA-V or EU-TIRADS-4) maximized sensitivity (92.3%) with acceptable specificity (70.0%); OR: 28.0. In the case of FLUS nodules, the combined criterion (rFNA-V or EU-TIRADS-5) maximized specificity (95.2%) with 57.7% sensitivity and a low percentage (13.9%) of positive nodules, OR: 27.0. In both types of nodules, the low risk category in EU-TIRADS and benign result of rFNA excluded cancer. Concluding, category III nodules with and without nuclear atypia differ in their risk of malignancy and, consequently, diagnostic criteria adopted for the evaluation of these nodules with rFNA and EU-TIRADS should be specific to AUS and FLUS nodules.

Hashimoto's Thyroiditis Does Not Influence the Malignancy Risk in Nodules of Category III in the Bethesda System

The aim of this study was to evaluate the risk of malignancy (RoM) in category III thyroid nodules of the Bethesda system in patients with and without Hashimoto thyroiditis (HT) and to analyze whether obtaining category III with a repeat FNA (rFNA) increases RoM. The study included 563 HT and 1250 non-HT patients; rFNA was performed in 349 and 575 patients, and surgical treatment in 160 and 390, respectively. There was no difference in RoM between HT and non-HT patients in the whole examined population (lower limit of RoM), nor in operated patients (upper limit of RoM), HT: 5.0−17.5%, non-HT: 4.7−15.1%. RoM in patients with AUS nodules (with nuclear atypia) was similar in both groups (HT: 21.7−40.0%, non-HT: 16.9−41.4%), as it was in patients with FLUS nodules (with architectural atypia) (HT: 3.5−13.3%, non-HT: 4.0−13.0%). In patients from both groups together, with category III diagnosed twice and AUS identified at least once, RoM was 16.7−50.0% and it was higher than that in patients with FLUS nodule diagnosed twice: 3.2−13.0% (p < 0.005). Concluding, RoM in category III nodules is not affected by the presence of HT. Subcategorization of category III nodules (FLUS vs. AUS) may provide guidance toward further follow-up or surgery in both groups.

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.

Do Ultrasound Patterns and Clinical Parameters Inform the Probability of Thyroid Cancer Predicted by Molecular Testing in Nodules with Indeterminate Cytology?

Background: Molecular testing (MT) is commonly used to refine cancer probability in thyroid nodules with indeterminate cytology. Whether or not ultrasound (US) patterns and clinical parameters can further inform the risk of thyroid cancer in nodules predicted to be positive or negative by MT remains unknown. The aim of this study was to test if clinical parameters, including patient age, sex, nodule size (by US), Bethesda category (III, IV, V), US pattern (American Thyroid Association [ATA] vs. American College of Radiology Thyroid Image Reporting and Data System [TI-RADS] systems), radiation exposure, or family history of thyroid cancer can modify the probability of thyroid cancer or noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) predicted by MT. Methods: We studied 257 thyroid nodules in 232 patients from 10 study centers with indeterminate fine needle aspiration cytology and informative MT results using the ThyroSeq v3 genomic classifier (TSv3). Univariate and multivariate logistic regression was used for data analysis. Results: The presence of cancer/NIFTP was associated with positive TSv3 results (odds ratio 61.39, p < 0.0001). On univariate regression, patient sex, age, and Bethesda category were associated with cancer/NIFTP probability (p < 0.05 for each). Although ATA (p = 0.1211) and TI-RADS (p = 0.1359) US categories demonstrated positive trends, neither was significantly associated with cancer/NIFTP probability. A multivariate regression model incorporating the four most informative non-MT covariates (sex, age, Bethesda category, and ATA US pattern; Model No. 1) yielded a C index of 0.653; R² = 0.108. When TSv3 was added to Model number 1, the C index increased to 0.888; R² = 0.572. However, age (p = 0.341), Bethesda category (p = 0.272), and ATA US pattern (p = 0.264) were nonsignificant, and other than TSv3 (p < 0.0001), male sex was the only non-MT parameter that potentially contributed to cancer/NIFTP risk (p = 0.095). The simplest and most efficient clinical model (No. 3) incorporated TSv3 and sex (C index = 0.889; R² = 0.588). Conclusions: In this multicenter study of thyroid nodules with indeterminate cytology and MT, neither the ATA nor TI-RADS US scoring systems further informed the risk of cancer/NIFTP beyond that predicted by TSv3. Although age and Bethesda category were associated with cancer/NIFTP probability on univariate analysis, in sequential nomograms they provided limited incremental value above the high predictive ability of TSv3. Patient sex may contribute to cancer/NIFTP risk in thyroid nodules with indeterminate cytology.

Atypia and Follicular Lesions of Undetermined Significance in Subsequent Biopsy Result: What Clinicians Need to Know

Atypia and follicular lesions of undetermined significance (AUS/FLUS) is the most controversial category of The Bethesda System. The risk of malignancy (ROM) in this group is estimated as 5–15%, however, the occurrence of two or more subsequent biopsy results with AUS/FLUS diagnosis makes these clinical situations more complex. We evaluated the ROM and prognostic value of aggressive ultrasound (US) features in 342 patients with thyroid nodules (TNs) with subsequent biopsy results of AUS/FLUS. We assessed US features and compared them with the final histopathological diagnosis. Overall, 121 (35.4%) individuals after first AUS/FLUS diagnosis underwent surgery and 221 (64.6%) patients had repeated biopsies. The ROM after first, second, and third biopsies with subsequent AUS/FLUS diagnosis were 7.4%, 18.5%, and 38.4% respectively. We demonstrated significantly higher rates of occurrence of aggressive US features in patients with malignancy (p < 0.0001). The age <55 years old was also a significant risk factor for TC (p = 0.044). Significant associations were found between aggressive US features and malignancy in patients after first diagnosis of AUS/FLUS (p < 0.05). The juxtaposition of US features with the number of biopsy repetitions of TN with consecutive AUS/FLUS diagnoses may simplify the decision-making process in surgical management. Two or three consecutive biopsy results with AUS/FLUS diagnosis increases the ROM.

Malignancy outcomes and the impact of repeat fine needle aspiration of thyroid nodules with Bethesda category III cytology: A multicenter experience

BACKGROUND

The clinical management of Bethesda III category thyroid nodules has some undefined points and differs among centers and conflicting malignancy rates are present in the literature. The aim of this study was to investigate the Bethesda category III thyroid nodule outcomes in our centers, to determine malignancy rates and also to evaluate clinical and sonographic features which may help to predict malignancy.

METHODS

This retrospective study included 333 patients with thyroid nodules who had Bethesda category III on fine needle aspiration (FNA) in three tertiary medical centers of Turkey.

RESULTS

Among 333 patients, 302 had appropriate follow up. Eighteen patients received thyroidectomy after the first FNA, with a malignancy rate of 38.89% (7/18) and 284 patients received a second FNA. After the second FNA, thyroidectomy was performed in 80 patients and 41 patients needed the third FNA. Thirteen thyroidectomies were performed after the third FNA. Totally 111 patients received thyroidectomy with a malignancy rate of 48.65% (54/111) among patients with surgery and the lower bound was detected as 17.88% (54/302). Of these patients the malignancy rates of patients receiving thyroidectomy with two and three FNAs were 47.50% (38/80) and 69.23% (9/13), respectively. Hypoechogenicity, microcalcification, and irregular margin were found as good predictors for malignancy.

CONCLUSION

We demonstrated that the malignancy rate was 48.65% in patients receiving thyroidectomy. We showed a higher malignancy rate than the traditionally rate of 5%-15%. This study showed that repeat FNAs decrease the rate of unnecessary surgery performed for benign lesions by increasing the rate of malignancy detection.

The Correlation of Age with Prognosis of Atypia of Undetermined Significance and Follicular Lesion of Undetermined Significance in Thyroid Nodules

Purpose

Although some prognostic variables and risk factors for thyroid cancer (TC) are age-related, the association between age and the risk of TC in patients with thyroid nodules (TNs) assigned to atypia of undetermined significance (AUS) and follicular lesion of undetermined significance (FLUS) is poorly estimated. The aim of this study was to assess the histopathology of AUS/FLUS and the risk of TC according to the age of the patients at the time of AUS/FLUS diagnosis.

Patients and Methods

Among 5021 individuals treated for TNs at one institution from 2008 to 2018, 161 (3.2%) patients with 161 TNs assigned to the AUS/FLUS category (1 nodule per patient) were selected and stratified by age at initial diagnosis: <55 years, 55–75 years and >75 years. Logistic regression analysis was used to estimate the association of age with the risk of TC diagnosis.

Results

Ninety-one (56.52%) patients <55 years old, 58 (36.02%) patients 55–75 years old, and 12 (7.45%) individuals >75 years old were identified. There were 130 (80.7%) females and 31 (19.3%) males with a mean age of 50.6 ± 16.12 years. Among the evaluated TNs, 142 (88.2%) were ultimately diagnosed as benign, and 19 (11.8%) were diagnosed as malignant. Younger age in patients was significantly related to malignancy outcome (p=0.024 for age <55 years). Patients aged 55–75 years had a significantly lower risk of TC than the other age categories (p=0.040). The risks of high vascularity and fast tumor growth were significantly higher in the youngest category than in the other categories (age <55 years old: p=0.045 and p=0.002, respectively).

Conclusion

Although patients with TNs classified as AUS/FLUS by ultrasound-guided fine needle aspiration biopsy (UG-FNAB) are not typically qualified for surgery, it is worth noting that younger patients with an AUS/FLUS diagnosis might be at a higher risk of TC.

Prevalence of cancer and the benign call rate of afirma gene classifier in 18 F-Fluorodeoxyglucose positron emission tomography positive cytologically indeterminate thyroid nodules

BACKGROUND

18 F-Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) positive (PET+) cytologically indeterminate thyroid nodules (ITNs) have variable cancer risk in the literature. The benign call rate (BCR) of Afirma Gene Classifier (Gene Expression Classifier, GEC, or Genome Sequence Classifier, GSC) in (PET +) ITNs is unknown.

METHODS

This is a retrospective study at our institution of all patients with (PET+) ITNs (Bethesda III/IV) from 1 January 2010 to 21 May 2019 who underwent Afirma testing and/or surgery or repeat FNA with benign cytology.

RESULTS

Forty-five (PET+) ITNs were identified: 31 Afirma-tested (GEC = 20, GSC = 11) and 14 either underwent surgery (n = 13) or repeat FNA (Benign cytology) (n = 1) without Afirma. The prevalence of cancer and noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) including only resected nodules and ITN with repeat benign FNA (n = 33) was 36.4% (12/33). Excluding all Afirma "suspicious" non-resected ITNs and assuming all Afirma "benign" ITNs were truly benign, that prevalence was 28.6% (12/42). The BCR with GSC was 64% compared to 25% with GEC (p = 0.056). Combining GSC/GEC-tested ITNs, the BCR was higher in ITNs demonstrating low/very low-risk sonographic pattern by the American Thyroid Association (ATA) classification and ITNs scoring <4 by the American College of Radiology Thyroid Imaging, Reporting and Data System (ACR-TI-RADS) than ITNs with higher sonographic pattern/score (p = 0.025).

CONCLUSIONS

The prevalence of cancer/NIFTP in (PET+) ITNs was 28.6-36.4% depending on the method of calculation. The BCR of Afirma GSC was 64%. Combining Afirma GEC/GSC-tested ITNs, BCR was higher in ITNs with a lower risk sonographic pattern.

Surgical Outcome and Malignant Risk Factors in Patients With Thyroid Nodule Classified as Bethesda Category III

BACKGROUND

Thyroid nodules are a very common finding in the general population. Fine-needle aspiration (FNA) has been recommended as the initial test for the evaluation of thyroid nodules. The trend on reporting as atypia of undetermined significance (AUS) has been significantly increased, but the malignant risk is still controversial among different studies. The aim of this study is to investigate the malignancy risk of thyroid nodules reported as Bethesda category III (AUS/FLUS) on initial FNA.

METHOD

We reviewed 272 papillary thyroid cancer (PTC) patients with suspicious thyroid nodules who underwent fine-needle aspiration and received surgical treatment during 2019 to 2020.

RESULTS

One hundred ten (40.4%) patients were diagnosed with PTC. Multivariate analysis showed that microcalcification (p = 0.037, OR = 2.260, 95% CI: 1.051-4.860), shape (p = 0.003, OR = 4.367, 95% CI: 1.629-11.705), diameters (p = 0.002, OR = 0.278, 95% CI: 0.123-0.631), anti-thyroglobulin antibodies (TGAb) (p = 0.002, OR = 0.150, 95% CI: 0.046-0.494), anti-thyroid peroxidase antibody (A-TPO) (p = 0.009, OR = 4.784, 95% CI: 1.486-15.401), and nodule goiter (p < 0.001, OR = 0.100, 95% CI: 0.046-0.217) were independent malignant risk factors in patients with thyroid nodule classified as Bethesda category III.

CONCLUSION

In this study, malignant risk factors in patients with thyroid nodule classified as Bethesda category III were significantly associated with preoperative serum TGAb, A-TPO, microcalcification, irregular shape, and nodule diameters. Nodules with malignant factors should be carefully elevated; surgery may be the better option for those patients.

American Thyroid Association Sonographic Risk and Afirma Gene Expression Classifier Alone and in Combination for the Diagnosis of Thyroid Nodules with Bethesda Category III Cytology

Background: The Afirma gene expression classifier (GEC) has been used to aid in the diagnosis and management of thyroid nodules having Bethesda category III fine-needle aspiration cytologic diagnosis (B3 nodules). The American Thyroid Association sonographic risk stratification system for thyroid nodules (ATA-US) may stratify B3 nodules and aid in the decision to order a molecular test. The aim of this study was to assess the association between ATA-US and GEC as well as to determine their individual and combined diagnostic performances when applied to B3 nodules. Methods: A retrospective single-center study included B3 nodules that had undergone evaluation by GEC. Each ultrasound was reviewed by three radiologists, and nodules were classified using the 2015 ATA sonographic risk categories. Nodules were determined to be benign or malignant based on surgical pathology or minimum 11 months of follow-up. Positive predictive values (PPV) and negative predictive values (NPV) were calculated for GEC, ATA-US, and GEC across all ATA-US categories. Results: One hundred twenty-six B3 nodules with GEC results were included and deemed benign or malignant based on final pathology or follow-up. Prevalence of malignancy was 32%. The rate of malignancy was similar in the ATA-US high suspicion (HS) and intermediate suspicion (IS) categories at 42% and 38%, respectively; and lower in nodules with low suspicion sonography (LS) and very low suspicion sonography (VLS) at 23% and 11%, respectively. The PPV and NPV of ATA-US was calculated by designating HS or IS sonography as a "positive" test and the lower risk categories as "negative." ATA-US had a PPV of 40% and NPV of 79%. The GEC PPV was 40% and NPV was 83%. The PPV of GEC was 50% in nodules with HS or IS ATA-US and lower at 28% and 20%, respectively, in LS and VLS nodules. The NPV of GEC was 80% in HS, 77% in IS, 84% in LS, and 100% in VLS sonography categories. Conclusions: In B3 nodules, ATA-US and GEC have similar diagnostic performance. The PPV of GEC varies across ATA-US categories, while the NPV remains similar. These data support the need for future prospective studies.

Can the American Thyroid Association, K-Tirads, and Acr-Tirads Ultrasound Classification Systems Be Used to Predict Malignancy in Bethesda Category IV Nodules?

OBJECTIVE

Management of thyroid nodules with Bethesda category III and IV cytology on fine needle aspiration (FNA) is challenging as they cannot be adequately classified as benign or malignant. Ultrasound (US) patterns have demonstrated the utility in evaluating the risk of malignancy (ROM) of Bethesda category III nodules. This study aims to evaluate the value of 3 well-established US grading systems (American Thyroid Association [ATA], Korean Thyroid Imaging Reporting and Data System [Korean-TIRADS], and The American College of Radiology Thyroid Imaging Reporting and Data System [ACR-TIRADS]) in determining ROM in Bethesda category IV nodules.

METHODS

Ninety-two patients with 92 surgically resected thyroid nodules who had Bethesda category IV cytology on FNA were identified. Nodule images were retrospectively graded using the 3 systems in a blinded manner. Associations between US risk category and malignant pathology for each system were analyzed.

RESULTS

Of the 92 nodules, 56 (61%) were benign and 36 (39%) were malignant. Forty-seven per cent of ATA high risk nodules, 53% of K-TIRADS category 5 nodules, and 50% of ACR-TIRADS category 5 nodules were malignant. The ATA high-risk category had 25% sensitivity, 82% specificity, 47% positive predictive value (PPV) for malignancy. K-TIRADS category 5 had 25% sensitivity, 85% specificity, 53% PPV for malignancy. ACR-TIRADS category 5 had 25% sensitivity, 84% specificity, 50% PPV for malignancy. None of the 3 grading systems yielded a statistically significant correlation between US risk category and the ROM (P = .30, .72, .28).

CONCLUSION

The ATA, Korean-TIRADS, and ACR-TIRADS classification systems are not helpful in stratifying ROM in patients with Bethesda category IV nodules. Clinicians should be cautious of using ultra-sound alone when deciding between therapeutic options for patients with Bethesda category IV thyroid nodules.

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

OBJECTIVE

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Malignancy Rate in Thyroid Nodules with Atypia or Follicular Lesion of Undetermined Significance

Introduction  Atypia of undetermined significance (AUS) or follicular lesion of undetermined significance (FLUS) is one of the six diagnostic categories of the Bethesda System for Reporting Thyroid Cytopathology. The prevalence of malignancy among Bethesda category III cytology is variable, ranging from 5% to 37% in the literature. Objective  To determine the rate of malignancy in thyroid nodules reported as Bethesda category III. Methods  A total of 495 patients underwent surgical intervention for thyroid nodules from January 2015 to December 2017. The present study included 81 cases reported as Bethesda category III, and their medical records were reviewed. Results  Out of 495 fine-needle aspiration cytology samples, 81 (16.4%) samples were labeled as AUS/FLUS. Among these 81 patients, the mean age was 43.0 years (± 13.9), with only 11 (14%) patients older than 55 years of age. Most of our patients were female ( n  = 69; 85.2%), and the rest were male. The rate of malignancy based on the final histology was of 33.3% ( n  = 27). The majority were 17 cases (21%) of papillary carcinoma, followed by follicular carcinoma ( n  = 6) (7.4%). Conclusion  The risk of malignancy can be higher than it is commonly believed, and guidelines should be based on the data from the institutions themselves for a better assessment of the outcomes.

Approaching Indeterminate Thyroid Nodules in the Absence of Molecular Markers: "The BETH-TR Score"

CONTEXT

Given the lack of easy access to molecular markers for indeterminate thyroid nodules (Bethesda (BETH) category III, IV), the clinician can either decide to get a second opinion from an expert high-volume thyroid cytopathologist, redo the FNAC after a period of 3-6 months, or send the patient for a diagnostic hemithyroidectomy. Reviewing the sonographic risk features is also one way of triaging these nodules. The ACR-TIRADS (TR) is an objective method of sonographic risk assessment and is superior to other forms of sonographic classification.

AIM

We propose combining the scoring of the TR category and BETH category (both expressed as a numerical value and summated) and look at the score which could potentially guide the clinician in deciding whom to send for surgery.

SETTINGS AND DESIGN

Observational prospective collection of consecutive patient data from the thyroid FNAC clinic.

STATISTICAL ANALYSIS USED

The BETH categories were represented numerically and summated with the TR category. The categorical outcome variables of benign and malignant nodules and the summated score was analyzed using the Kruskal-Wallis test.

RESULTS

We analyzed 450 FNAC data, out of which 403 were thyroid nodule aspirates. Out of these nodules, 96 of them underwent surgery and 64% of these nodules were malignant on final histopathology (malignant = 62 and benign = 34). The mean size of the benign nodules was 3.6 ± 2.2 cm compared to 2.8 ± 1.8 cm of the malignant nodules. After excluding those with BETH 1 (n = 4), the mean BETH-TR score for benign nodules was 6 ± 1.4 and malignant nodules 9.4 ± 2.1 (P < 0.0001). The BETH-TR score progressively increased from 7.3 ± 0.92 in follicular thyroid cancers (FTC) to 8.6 ± 1.4 in follicular variant papillary thyroid cancer (FVPTC) to 10 ± 1.3 in classic papillary thyroid cancers (PTC). Among the indeterminate nodules (BETH III and IV; n = 40), the BETH-TR score of benign nodules was 6.75 ± 1 and malignant nodules was 7.5 ± 0.72 (P value = 0.01). A BETH-TR score ≥7 gave a sensitivity of 92% specificity of 74% and correctly identified malignant nodules in 86% of cases (likelihood ratio 3.5; ROC area: 0.8841; CI 0.79-0.94).

CONCLUSION

A combined sonocytological BETH-TR score is one way to triage the management of indeterminate thyroid nodules. A BETH-TR score ≥7 gave a sensitivity of 92% specificity of 74% and correctly identified malignant nodules in 86% of cases.

Can Repeat Biopsies Change the Prognoses of AUS/FLUS Nodule?

OBJECTIVE

Experience with atypia of undetermined significance/follicular lesions of undetermined significance (AUS/FLUS) showed that this category exhibited a marked variability in incidence and malignant outcome in resection specimens. We aimed to determine the utility of repeated fine-needle aspiration biopsies (FNABs) and ultrasonography to determine the malignancy rate in AUS/FLUS nodules.

METHODS

23,587 nodules were biopsied, and 1,288 had at least one AUS/FLUS cytology. Ultrasonographic features including solid hypoechoic status, irregular margins, microcalcifications, nodule taller than wider, or an extrathyroidal extension were also recorded. Nodules for which only 1 FNAB revealed AUS/FLUS cytology were termed Group 1; nodules that underwent 2, 3, and 4 FNABs were termed Groups 2, 3 and 4, respectively. We compared these groups according to malignancy rates.

RESULTS

576 of nodules underwent only 1 FNAB (Group 1); 505, 174, and 33 underwent 2 (Group 2), 3 (Group 3), and 4 FNABs (Group 4), respectively. Fifty-six (30.6%), 45 (27.3%), 18 (30%), and 5 (33.3%) of Groups 1-4 were malignant, respectively. The risk of malignancy was similar in each group (p > 0.05). Suspicious ultrasonographic features were encountered in malignant nodules more than benign nodules (p < 0.05, for each).

CONCLUSION

Repeat biopsy of AUS/FLUS nodules did not enhance the identification of malignancy. Ultrasonographic features may be a better guide for the decision of either surveillance or diagnostic surgery.

Prognostic factors in thyroid carcinomas: a 17-year outcome study

Objectives The aim of our study was to evaluate the survival rate of all thyroid carcinomas (TCs) diagnosed in the 1999-2015 period in the Republic of North Macedonia and to analyze the prognostic influence of several characteristics on development of distant metastases, as well as to analyze the prognostic effect of seven clinical and constitutional features on mortality. Material and methods A retrospective analysis of medical data from all TCs diagnosed in 1999-2015 was performed. The survival rate of all types of TCs was estimated using the Kaplan Meier method. Univariate and multivariate logistic regression analysis was applied for evaluation of the predictive role of seven clinical and constitutional characteristics for development of distant metastases, and the univariate Cox-proportional model was applied for evaluation of the predictors for mortality. Results A total of 422 TC cases were diagnosed in the 17-year period, with an average survival time of 212.99 months. Results of the univariate regression analysis showed that dimension at initial ultrasound and histopathological type of tumor were significantly predictive variables for distant metastases. Multifocal tumors vs. unifocal tumors < 15 mm significantly increased the probability of distant metastases by 7.401 (p = 0.005, 95% CI = 1.817-30.190) times. Age, initial lymph node involvement, number of radioiodine therapies, and histopathology of the tumor were selected as independent significant predictors for mortality. Conclusion Our results showed an excellent overall prognosis of thyroid tumors in the Macedonian population. The dimension of the tumor, multifocality, and histopathological type were the most relevant prognostic predictive features for development of distant metastases.

Predictors for malignancy risk in subcentimeter thyroid nodules categorized as atypia/follicular lesion of undetermined significance by fine needle aspiration

Little work has been done on the prediction of malignancy risk in patients with subcentimeter thyroid nodule (TN) categorized as atypia/follicular lesion of undetermined significance (AUS/FLUS). We performed a retrospective analysis on the medical records of subcentimeter TNs whose initial fine-needle aspiration (FNA) diagnosis was AUS/FLUS at our center between November 2013 and August 2018. Univariate analysis and multivariate logistic regression analysis were used to select independent factors associated with malignancy. Of the 324 patients who were classified as AUS/FLUS on initial FNA, 153 patients underwent surgical procedures and showed an associated malignancy rate of 45.10% (69/153). The malignancy rates in AUS/FLUS settings with and without repeat FNA were 38.30% (18/47), and 48.11% (51/106), respectively, p = 0.260. Multivariate logistic regression analysis revealed that age < 55 (OR 3.015, 95% CI 1.196-7.596), microcalcification (OR 9.162, 95% CI 3.332-25.916) and taller than wide shape (OR 10.785, 95% CI 4.108-28.319) were three independent predictors for malignancy. The malignancy rates in the patients with one or none of predictor and patients with two or three above predictors were 20.5% (17/83) and 74.3% (52/70), respectively, p < 0.001 (OR 11.216, 95% CI 5.266-23.885). In conclusion, our study showed that for subcentimeter TNs with AUS/FLUS category, patient's age, taller than wide shape and microcalcification were three independent predictive factors for malignancy, which was helpful for decision-making of surgery or observation in such patient population.

Ultrasound characteristics of thyroid nodules facilitate interpretation of the malignant risk of Bethesda system III/IV thyroid nodules and inform therapeutic schedule

Background

This study was designed to explore whether ultrasound of thyroid nodules facilitates the interpretation of the malignant risk of Bethesda III/IV thyroid nodules to inform further therapies.

Methods

We reviewed patient records in which the results of ultrasound‐guided fine‐needle aspiration (US‐FNA) were classified by the Bethesda III/IV in our institution between January 2016 and June 2018. Studies were retrieved from PubMed, Cochrane Central Register of Controlled Trials, ISI Web of Science, Science Direct, Wiley Online Library, EMBASE, China National Knowledge Infrastructure, WanFang, and Chinese VIP. The odds ratio (OR) was used to measure associations between risk factors and thyroid nodule malignancy.

Results

Fifty‐nine cases of Bethesda III/IV with corresponding surgeries were included, and the malignancy risk was 54.2%. Meta‐analysis revealed irregular borders, solitary nodules, hypoechogenicity, microcalcifications, and being taller than wide, all of which increased the malignancy risk of thyroid nodules. Combined ORs for these factors were 4.08 (95% CI: 2.34‐7.14, P < .001), 2.18 (95% CI: 1.39‐3.42, P = .001), 2.02 (95% CI: 1.35‐3.01, P = .001), 3.21 (95% CI: 2.26‐4.56, P < .001), and 4.35 (95% CI: 3.07‐6.15, P < .001), respectively.

Conclusion

As the risk of malignancy for papillary thyroid carcinoma (PTC) is high, when any one of the five ultrasound features of malignancy were confirmed, repeated FNA is recommended to confirm PTC‐type malignancy, even though nodules were Bethesda III/IV classification. However, repeated FNA should be avoided when none of these ultrasound features are identified because repeated FNA does not contribute to identifying non‐PTC type malignancies, such as follicular thyroid carcinoma and poorly differentiated thyroid carcinoma.

Diagnostic Performance of Ultrasound Patterns by K-TIRADS and 2015 ATA Guidelines in Risk Stratification of Thyroid Nodules and Follicular Lesions of Undetermined Significance

OBJECTIVE. The objective of our study was to assess the malignancy rates of thyroid nodules in the cytologically determined subclass of atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) and to assess the diagnostic performance of ultrasound (US) patterns defined by the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) and the 2015 American Thyroid Association (ATA) guidelines for risk stratification of AUS/FLUS nodules. MATERIALS AND METHODS. From January 2010 to December 2016, 1340 thyroid nodules were diagnosed as AUS/FLUS via fine-needle aspiration biopsy. Of these, 683 cytopathologically confirmed nodules were included in this study. Each nodule was assigned to a category and US pattern, as defined by the K-TIRADS and ATA guidelines. US patterns were compared between benign and malignant nodules, and malignancy rates were calculated according to the subclasses of AUS/FLUS nodules and the K-TIRADS and ATA guidelines. Predictors of malignancy were assessed using logistic regression analysis. RESULTS. The overall malignancy rate of AUS/FLUS nodules was 47.4% (324/683). There were significant differences in malignancy risk among the subclasses (p = 0.001). There were significant differences in malignancy rates according to US patterns, K-TIRADS categories, and ATA categories (p < 0.001). The malignancy rates in the K-TIRADS categories of benign, low, intermediate, and high suspicion were 0%, 1.99%, 34.66%, and 89.00%, respectively (p < 0.001). The malignancy rates in the ATA categories of benign, very low, low, intermediate, and high suspicion were 0%, 0%, 3.33%, 33.54%, and 87.67% (p < 0.001). CONCLUSION. AUS/FLUS nodules with a final diagnosis of malignancy had significantly higher rates of suspicious US features and different K-TIRADS and ATA categories than benign nodules. US categories by K-TIRADS and ATA guidelines can be useful in predicting malignancy and risk stratification, and management planning can be adjusted according to US pattern.

European Perspective on 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: Proceedings of an Interactive International Symposium

BACKGROUND

The American Thyroid Association (ATA) management guidelines for patients with thyroid nodules and differentiated thyroid cancer (DTC) are highly influential practice recommendations. The latest revision appeared in 2015 ("ATA 2015"). These guidelines were developed predominantly by North American experts. European experts frequently have different perspectives, given epidemiological, technological/methodological, practice organization, and medicolegal differences between the respective regions.

SUMMARY

Divergent viewpoints were the focus of an invited symposium organized by the European Association of Nuclear Medicine involving 17 European thyroidologists, four ATA Guidelines Taskforce members, and an audience of 200 international experts. The group discussed the preoperative assessment of thyroid nodules, surgery and the role of pathology, radioiodine (RAI) therapy (RAIT), the assessment of initial therapy and dynamic risk stratification, and the treatment of persistent disease, recurrences, and advanced thyroid cancer. The dialogue resulted in this position paper contrasting European and ATA 2015 perspectives on key issues. One difference pertains to the permissiveness of ATA 2015 regarding lobectomy for primary tumors ≤4 cm. European panelists cited preclusion of RAIT, potential need for completion thyroidectomy, frequent inability to avoid chronic thyroid hormone replacement, and limitations of supportive evidence as arguments against widely applying lobectomy. Significant divergence involved ATA 2015's guidance regarding RAIT. European panelists favored wider use of postoperative RAIT than does ATA 2015. Rationales included the modality's association with favorable patient outcomes and generally limited toxicity, and lack of high-quality evidence supporting withholding RAIT. Additionally, European panelists favored recombinant human thyrotropin (rhTSH) in more settings than does ATA 2015, citing avoidance of hypothyroid morbidity and quality-of-life impairment, without apparent sacrifice in oncologic outcomes. Based on clinical evidence plus theoretical advantages, European experts advocated dosimetric versus fixed-activity RAIT approaches for advanced DTC. European panelists noted that the ATA 2015 risk-stratification system requires information sometimes unavailable in everyday practice. ATA 2015 recommendations regarding RAI-refractory DTC should consider potential palliative benefits of RAIT in patients who also have RAI-susceptible lesions.

CONCLUSIONS

European panelists suggested modifications to approximately one-third of ATA 2015 recommendations. Varying European and ATA 2015 perspectives can stimulate analysis and discussion of the literature and performance of primary research to resolve discrepant recommendations and potentially improve patient outcomes.

WHICH FACTORS ARE ASSOCIATED WITH MALIGNANCY IN THYROID NODULES CLASSIFIED AS BETHESDA CATEGORY 3 (AUS/FLUS) AND HOW DO THEY INFLUENCE THE PATIENT'S MANAGEMENT?

Background

Thyroid nodules are a common pathology worldwide. Fine needle aspiration biopsy (FNAB) is an important diagnostic method for the investigation of malignancy in thyroid nodules. However, according to the Bethesda System used to classify the results, patients with atypia of undetermined significance/follicular lesion of undetermined significance (AUS / FLUS) may not be classified as benign or malignant. Therefore, it may be necessary to determine some clinical risk factors to apply the best treatment in these patients.

Aim

To determine the factors that increase the risk of malignancy in this patient group.

Methods

A retrospective study including 138 patients with an FNAB categorized as AUS/FLUS and operated between June 2015-September 2018. Demographical, Laboratory (TSH) and Ultrasound variables (number, size and characteristics of nodules) of the patients were compared among postoperative histopathological results.

Results

Hypo-echoic structure, microcalcification and irregular margin of the nodules were detected to be associated with malignancy in patients with FNAB results of AUS/FLUS (p <0.001).

Conclusion

We suggest that surgical treatment should be considered if the patients have nodules with the hypo-echoic structure, microcalcification and irregular margin with an FNAB histopathological result of AUS / FLUS.

BRAF V600E vs. TIRADS in predicting papillary thyroid cancers in Bethesda system I, III, and V nodules

Objective

Bethesda System for Reporting Thyroid Cytopathology (BSRTC) categories I, III, and V account for a significant proportion of fine needle aspiration cytology (FNAC) diagnoses. This study aimed to compare the diagnostic efficacy of BRAF^V600E mutation and the Thyroid Imaging Reporting and Data System (TIRADS) classification in differentiating papillary thyroid cancers (PTCs) from benign lesions among BSRTC I, III, and V nodules.

Methods

A total of 472 patients with 479 nodules were enrolled in this prospective study. Ultrasound, BRAF^V600E mutation testing, and FNAC were performed in each nodule, followed by surgery or regular ultrasound examination.

Results

In the BSRTC I category, BRAF^V600E showed similar sensitivity, higher specificity, and lower accuracy when compared with TIRADS. In the BSRTC III/V category, the sensitivity, specificity, and accuracy of BRAF^V600E were similar to those of TIRADS. In comparison to BRAF^V600E alone, the combination of the two methods significantly improved sensitivity (BSRTC I: 93.6% vs. 67.7%, P < 0.01; BSRTC III: 93.8% vs. 75.0%, P < 0.01; BSRTC V: 96.0% vs. 85.3%, P < 0.001). When compared with TIRADS alone, the combination improved sensitivity in BSRTC I nodules (93.6% vs. 74.2%, P < 0.05), increased sensitivity and decreased accuracy in BSRTC III nodules (93.8% vs. 75.0%, P < 0.01, 91.0% vs. 93.6%, P < 0.01), and improved both sensitivity and accuracy in BSRTC V nodules (96.0% vs. 82.0%, P < 0.001; 94.2% vs. 81.3%, P < 0.001).

Conclusions

BRAF^V600E exhibited higher specificity and lower accuracy compared with TIRADS in BSRTC I nodules, while the two methods showed similar diagnostic value in BSRTC III/V nodules. The combination of the two methods distinctly improved sensitivity in the diagnosis of PTCs in BSRTC I, III, and V nodules.

Both Ultrasound Features and Nuclear Atypia are Associated with Malignancy in Thyroid Nodules with Atypia of Undetermined Significance

BACKGROUND

The optimal management of thyroid nodules that undergo fine-needle aspiration (FNA) with findings of atypia of undetermined significance (AUS) is unclear. Categorizing nodules by AUS subtype and ultrasound characteristics may improve risk stratification. Therefore, the purpose of this study is to evaluate the association between AUS subtype and ultrasound features on risk of malignancy (ROM).

METHODS

We performed a review of all patients with a thyroid nodule who underwent an FNA at our institution between January 2010 and November 2015. Patients with AUS were divided into groups with (1) nuclear atypia, (2) architectural atypia, or (3) Hurthle cell atypia. Their ultrasound features were assessed using the American Thyroid Association (ATA) thyroid nodule sonographic patterns. We conducted a univariate and multivariable analysis to determine the association between AUS subtype and other variables of interest with ROM.

RESULTS

Of the 3428 thyroid nodules that underwent FNA, 237 (6.9%) had AUS. Of the 97 surgically resected nodules, 67 (69%) were benign and 30 (31%) were malignant. On univariate analysis nuclear atypia (p < 0.01) was associated with a thyroid malignancy. On multivariable analysis, both ATA high-risk ultrasound features (p = 0.04, odds ratio [OR] 3.68) and nuclear atypia (p < 0.01, OR 11.8) were independently associated with a final diagnosis of thyroid carcinoma.

CONCLUSIONS

Nuclear atypia and ATA high-risk ultrasound features are useful in identifying patients with AUS that are at a higher risk of thyroid malignancy. Surgeons should take these factors into consideration when evaluating patients with AUS.

Thyroid cancer detection rate and associated risk factors in patients with thyroid nodules classified as Bethesda category III

Background Ultrasound guided fine-needle aspiration (FNA) is a standard procedure for thyroid nodules management and selecting patients for surgical treatment. Atypia of undetermined significance (AUS) or follicular lesion of undetermined significance (FLUS), as stated by The Bethesda System for Reporting Thyroid Cytopathology, is a diagnostic category with an implied malignancy risk of 5-15%. The aim of our study was to review cytology and histopathology reports, as well as clinical and ultrasound data, for thyroid nodules reported as AUS/FLUS, in order to evaluate the malignancy rate and to assess factors associated with malignant outcome. Patients and methods A total of 112 AUS/FLUS thyroid nodules in 105 patients were evaluated, of which 85 (75.9%) were referred to surgery, 21 (18.8%) were followed-up by repeat FNA and 6 nodules (5.3%) were clinically observed. Each was categorized in two final diagnostic groups - benign or malignant, which were further compared to clinical data of patients and ultrasonographic features of the nodules. Results Final diagnosis of malignancy was reached in 35 cases (31.2%) and 77 (68.8%) had benign lesions. The most frequent type of cancer was papillary thyroid carcinoma (PTC) - 58.1% PTC and 25.8% had follicular variant of PTC. Patients' younger age, smaller nodule size, hypoechoic nodule and presence of calcifications were shown to be statistically significant risk factors for malignancy. Conclusions The rate of malignancy for the AUS/FLUS diagnostic category in our study was higher than estimated by the Bethesda System. Clinical and ultrasound factors should be considered when decision for patient treatment is being made.

Use of the thyroid imaging, reporting, and data system (TI-RADS) scoring system for the evaluation of subcentimeter thyroid nodules

BACKGROUND

The American Thyroid Association (ATA) recommends fine-needle aspiration (FNA) biopsy of nodules measuring >1.5 cm with low-suspicion sonographic patterns or >1.0 cm with high/intermediate-suspicion features. Routine biopsy of nodules <1 cm is not recommended. However, despite these recommendations, subcentimeter nodules are often referred for FNA biopsy.

METHODS

This was a retrospective chart review of consecutive thyroid FNAs during an 18-month period (1157 patients, 1491 nodules, 2016-2017) to evaluate age, sex, medical history, diagnoses, and follow-up. Radiographic information was used to identify 61 subcentimeter nodules (4%) from 57 patients. Ultrasound studies were re-evaluated using criteria according to the American College of Radiology Thyroid Imaging, Reporting, and Data System (TI-RADS).

RESULTS

Reported reasons for biopsy included a larger companion nodule (44%), a personal or family history of cancer (26%), or a suspicious sonogram, including calcification and/or irregular contours (16%). FNA diagnoses included: 69% benign (42 of 61 nodules), 10% papillary thyroid carcinoma (PTC) (6 of 61 nodules), and 15% atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) (9 of 61 nodules). Seven percent of nodules were unsatisfactory/nondiagnostic (4 of 61 nodules) compared with a 3% nondiagnostic rate for all sized nodules. Fifty-one nodules had an ultrasound available for re-review using the TI-RADS scoring system. A high TI-RADS score (4-5) was indicative of PTC in 29.4% of nodules. A low TI-RADS score (1-2) was indicative of PTC in 0% of nodules (P < .01). High and intermediate TI-RADS scores (3 and 4-5, respectively) were indicative of PTC/AUS/FLUS in 32% of nodules compared with 0% in those with low TI-RADS scores (P < .01).

CONCLUSIONS

The current results demonstrate successful use of the TI-RADS scoring system in evaluation of the risk of malignancy in subcentimeter nodules. Larger studies will be necessary to determine whether biopsy is warranted for TI-RADS high-subcentimeter nodules. Cancer Cytopathol 2018. © 2018 American Cancer Society.

Diagnostic Utility of Molecular and Imaging Biomarkers in Cytological Indeterminate Thyroid Nodules

Indeterminate thyroid cytology (Bethesda III and IV) corresponds to follicular-patterned benign and malignant lesions, which are particularly difficult to differentiate on cytology alone. As ~25% of these nodules harbor malignancy, diagnostic hemithyroidectomy is still custom. However, advanced preoperative diagnostics are rapidly evolving.This review provides an overview of additional molecular and imaging diagnostics for indeterminate thyroid nodules in a preoperative clinical setting, including considerations regarding cost-effectiveness, availability, and feasibility of combining techniques. Addressed diagnostics include gene mutation analysis, microRNA, immunocytochemistry, ultrasonography, elastosonography, computed tomography, sestamibi scintigraphy, [18F]-2-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET), and diffusion-weighted magnetic resonance imaging.The best rule-out tests for malignancy were the Afirma® gene expression classifier and FDG-PET. The most accurate rule-in test was sole BRAF mutation analysis. No diagnostic had both near-perfect sensitivity and specificity, and estimated cost-effectiveness. Molecular techniques are rapidly advancing. However, given the currently available techniques, a multimodality stepwise approach likely offers the most accurate diagnosis, sequentially applying one sensitive rule-out test and one specific rule-in test. Geographical variations in cytology (e.g., Hürthle cell neoplasms) and tumor genetics strongly influence local test performance and clinical utility. Multidisciplinary collaboration and implementation studies can aid the local decision for one or more eligible diagnostics.

Risk stratification of thyroid nodules with Bethesda category III results on fine-needle aspiration cytology: The additional value of acoustic radiation force impulse elastography

To assess the value of conventional ultrasound, conventional strain elastography (CSE) and acoustic radiation force impulse (ARFI) elastography in differentiating likelihood of malignancy for Bethesda category III thyroid nodules. 103 thyroid nodules with Bethesda category III results on fine-needle aspiration cytology (FNAC) in 103 patients were included and all were pathologically confirmed after surgery. Conventional ultrasound, CSE and ARFI elastography including ARFI imaging and point shear wave speed (SWS) measurement were performed. Univariate and multivariate analyses were performed to identify the independent factors associated with malignancy. Area under the receiver operating characteristic curve (Az) was calculated to assess the diagnostic performance. Pathologically, 65 nodules were benign and 38 were malignant. Significant differences were found between benign and malignant nodules in ARFI. The cut-off points were ARFI imaging grade ≥ 4, SWS > 2.94 m/s and SWS ratio > 1.09, respectively. ARFI imaging (Az: 0.861) had the highest diagnostic performance to differentiate malignant from benign nodules, following by conventional ultrasound (Az: 0.606 - 0.744), CSE (Az: 0.660) and point SWS measurement (Az: 0.725 - 0.735). Multivariate logistic regression analysis showed that ARFI imaging grade ≥ 4 was the most significant independent predictor. The combination of ARFI imaging with point SWS measurement significantly improved the specificity (100% vs. 80.0%) and positive predictive value (100 % vs. 72.9%) in comparison with ARFI imaging alone. ARFI elastography is a useful tool in differentiating malignant from benign thyroid nodules with Bethesda category III results on FNAC.

New perspectives in the diagnosis of thyroid follicular lesions

Thyroid nodules are very common, affecting 19%-67% of the adult population. However, about 10% of them harbor a malignant lesion. Consequently, the first aim in their clinical evaluation is to exclude malignancy. Fine-needle aspiration cytology (FNAC) represents the main diagnostic tool for the evaluation of thyroid nodules. However, FNAC has a main diagnostic limit, namely cellular atypias of indeterminate significance, which require surgical excision and histological examination to differentiate benign from malignant lesions. Histology reports show that approximately 80% of these patients harbor a benign lesion. Therefore, in order to reduce unnecessary thyroidectomy, over the last years, the cytological classification of thyroid nodules has been revised and a number of new instrumental and molecular approaches have been proposed. In the present article, we will attempt to summarize the most recent cytological, molecular and echographic strategies to enhance the diagnostic accuracy of preoperative thyroid follicular lesions. In particular, we will discuss the new cytological classifications from the Bethesda System for Reporting Thyroid Cytopathology (BSRTC), the British Thyroid Association-Royal College of Pathologists (PTA-RCPath) and the new Italian Society for Anatomic Pathology and Cytology (SIAPEC 2014. We will review molecular tests evaluated to ameliorate follicular lesion diagnosis as well as the clinical utility of the new echographic Thyroid Imaging Reporting and Data System (TI-RADS) score.

Risk of malignancy in thyroid nodules classified as TIR-3A: What therapy?

BACKGROUND

The aim of the present study was to assess the clinical applicability of the TIR3A category in managing thyroid nodules, to examine the malignancy rates of TIR 3A and TIR 3B nodules, and to suggest management guidelines for these nodules.

MATERIALS AND METHODS

Thyroid cytologies performed in patients referred to our Department between January 2014 and August 2016 were classified according to the guidelines published by the SIAPEC. 102 cases were included in this retrospective study and were divided into two groups: 19 TIR3A were included in group A and 83 TIR3B in group B.

RESULTS

In group A, malignancy was diagnosed in 4 (21.1%) cases, papillary thyroid cancer was found in 3 patients and follicular thyroid cancer in 1; one case was classified as microcarcinoma, in two cancer was multicentric and bilateral and in one central node metastases were observed. In Group B malignancy was diagnosed in 48 (57.8%) patients, papillary thyroid cancer was found in 36 patients and follicular cancer in 12; microcarcinoma was observed in 25 cases, 12 were unilateral multicentric and 7 bilateral multicentric; in 3 cases central node metastases were present.

CONCLUSION

Thyroid nodules with TIR3A cytology have a lower risk of malignancy than TIR3B cases, for which the new SIAPEC classification has proved accurate and effective. Malignancy rates in nodules with TIR3A cytology are higher than expected, although the real and accurate definition of the risk is extremely difficult. The recommendation to perform an accurate follow-up and repeat the fine-needle aspiration still appears the best option. For better management of patients with TIR3A cytology a careful assessment of risk factors and ultrasound characteristics is always needed. Further multicenter studies with longer follow-up are needed to better define the efficacy of this classification, the actual cancer risk, and the best management of these lesions.

Prevention of total thyroidectomy in noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) based on combined interpretation of ultrasonographic and cytopathologic results

OBJECTIVE

To explore the potential preoperative ultrasonography (US) and cytopathological features to avoid total thyroidectomy in NIFTP.

CONTEXT

Recently, it has been proposed that that noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP) be classified as tumours, rather than cancer.

PATIENTS

A total of 142 surgically proven follicular variant papillary thyroid carcinomas (FVPTCs; 45 NIFTP, 97 non-NIFTP; mean size: 20.4±11.0 mm, range: 10.0-65.0 mm) from 142 patients were included in this study.

MEASUREMENTS

Three preoperative features of thyroid nodules (each US finding, US and Bethesda category) were compared in NIFTP and non-NIFTP groups. The preoperative decision-making process to avoid total thyroidectomy in NIFTP was evaluated based on combination of those features.

RESULTS

In each US finding, there was only significantly less macrocalcification in the NIFTP group than in the non-NIFTP group (8.8% [4/45] vs 32.0% [31/97], P = .006). In US category, all of the NIFTP nodules were a low or intermediate suspicion (100% [45/45]). In Bethesda category, 26.7% [12/45] of the NIFTP was diagnosed as either suspicious malignancy or malignant, which increased the risk of a total thyroidectomy. In our study, a total thyroidectomy might be avoided in all of the NIFTP cases if lobectomy was selected for the nodules classified as a low or intermediate suspicion in US, despite being classified as a suspicious malignancy or malignant by cytopathology.

CONCLUSIONS

Combining the US and cytopathological results could sensitively reduce total thyroidectomy in cases of NIFTP.

Validation of American Thyroid Association Ultrasound Risk Assessment of Thyroid Nodules Selected for Ultrasound Fine-Needle Aspiration

OBJECTIVE

The aim of this study was to validate the American Thyroid Association (ATA) sonographic risk assessment of thyroid nodules.

METHODS

The ATA sonographic risk assessment was prospectively applied to 206 thyroid nodules selected for ultrasound-guided fine-needle aspiration (US-FNA), and analyzed with The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC), as well as surgical pathology for the subset undergoing surgical excision.

RESULTS

The analysis included 206 thyroid nodules averaging 2.4 cm (range 1-7 cm; standard error of the mean 0.07). Using the ATA US pattern risk assessment, nodules were classified as high (4%), intermediate (31%), low (38%), and very low (26%) risk of malignancy. Nodule size was inversely correlated with sonographic risk assessment, as lower risk nodules were larger on average (p < 0.0001). Malignancy rates determined by cytology/surgical pathology were high 100%, intermediate 11%, low 8%, and very low 2%, which were closely aligned with ATA malignancy risk estimates (high 70-90%, intermediate 10-20%, low 5-10%, and very low 3%). ATA US pattern risk assessment also appropriately predicted the proportion of nodules classified as malignant or suspicious for malignancy through TBSRTC classification-high (77%), intermediate (6%), low (1%), and very low 0%-as well as benign TBSRTC classification-high (0%), intermediate (47%), low (61%), and very low (70%) (p < 0.0001). Malignancy rates of surgically excised, cytologically indeterminate nodules followed ATA sonographic risk stratification (high 100%, intermediate 21%, low 17%, and very low 12%; p = 0.003).

CONCLUSION

This prospective study supports the new ATA sonographic pattern risk assessment for selection of thyroid nodules for US-FNA based upon TBSRTC and surgical pathology results. In the setting of indeterminate cytopathology, nodules categorized as atypia of undetermined significance/follicular lesion of undetermined significance with ATA high-risk sonographic patterns have a high likelihood of being malignant.

Risk Stratification of Thyroid Nodules With Atypia of Undetermined Significance/Follicular Lesion of Undetermined Significance (AUS/FLUS) Cytology Using Ultrasonography Patterns Defined by the 2015 ATA Guidelines

PURPOSE

The purpose of this study was to evaluate the predictive value of ultrasonography (US) patterns based on the 2015 American Thyroid Association (ATA) guidelines for malignancy in atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) nodules.

METHODS

From January 2014 to August 2015, 133 thyroid nodules that were initially diagnosed as AUS/FLUS on fine needle aspiration (FNA) were included in this study. Each nodule was assigned a category with US patterns defined by the ATA guidelines. Clinical characteristics and US patterns were compared between the benign and malignant nodules, and malignancy rates were calculated according to the ATA guidelines.

RESULTS

The malignancy rate in the very low suspicion group was 0.0% in AUS/FLUS nodules. When applying the ATA guidelines, significant differences existed for US patterns between the benign and malignant nodules in the AUS group ( P = .032) but not the FLUS group ( P = .168).

CONCLUSIONS

Ultrasonography patterns by the 2015 ATA guidelines can provide risk stratification for nodules with AUS cytology but not for ones with FLUS cytology. For nodules with AUS/FLUS cytology with the very low suspicion pattern of the ATA guidelines, follow-up US might be recommended instead of repeat FNA.

Ultrasound is helpful to differentiate Bethesda class III thyroid nodules: A PRISMA-compliant systematic review and meta-analysis

BACKGROUND

Fine-needle aspiration (FNA) is the most dependable tool to triage thyroid nodules for medical or surgical management. However, Bethesda class III cytology, namely "follicular lesion of undetermined significance" (FLUS) or "atypia of undetermined significance" (AUS), is a major limitation of the US-FNA in assessing thyroid nodules. As the most important imaging method, ultrasound (US) has a high efficacy in diagnosing thyroid nodules. This meta-analysis aimed to assess the role of US in evaluating Bethesda class III thyroid nodules.

METHODS

With keywords "Undetermined Significance," "Bethesda Category III," "Bethesda system," "Cytological Subcategory," "AUS/FLUS," "Atypia of Undetermined Significance," and "Ultrasound/US," papers in PubMed, Cochrane Library, Medline, Web of Science, Embase, and Google Scholar from inception to December 2016 were searched. A meta-analysis of these trials was then performed for evaluating the diagnostic value of thyroid ultrasound in Bethesda Category III thyroid nodules.

RESULTS

Fourteen studies including 2405 nodules were analyzed. According to the criteria for US diagnosis of thyroid nodules in each article, with any one of suspicious features as indictors of malignancy, US had a pooled sensitivity of 0.75 (95% CI 0.72-0.78) and a pooled specificity of 0.48 (95% CI 0.45-0.50) in evaluating Bethesda Class III Nodules. The pooled diagnostic odds ratio was 10.92 (95% CI 6.04-19.74). The overall area under the curve was 0.84 and the Q* index was 0.77. With any 2 or 3 of US suspicious features as indictors of malignancy, the sensitivity and specificity were 0.77 (95% CI 0.71-0.83) and 0.54 (95% CI 0.51-0.58), 0.66 (95% CI 0.59-0.73) and 0.71 (95% CI 0.68-0.74), respectively.

CONCLUSIONS

US was helpful for differentiating benign and malignant Bethesda class III thyroid nodules, with the more suspicious features, the more likely to be malignant.

The predictive value of sonographic images of follicular lesions - a comparison with nodules unequivocal in FNA - single centre prospective study

BACKGROUND

To determine the diagnostic efficacy of ultrasonographic malignancy risk features (UMRFs) in follicular lesions (FL) in a population with low risk of malignancy in FL and to compare it with a similar analysis in a group of patients with unequivocal cytology (UC): benign lesion (BL) or malignant neoplasm (MN).

METHODS

Presence of UMRFs (hypoechogenicity, solid echostructure, taller-than-wide shape, pathological vascularization, irregular margins, microcalcifications and macrocalcifications) and their sets were assessed in 322 FL: 202 follicular lesions of undetermined significance (FLUS) and 120 suspicious for follicular neoplasm (SFN) and 300 nodules with UC: 200 BL and 100 MN, subsequently evaluated histopathologically.

RESULTS

Cancers were confirmed in 100% nodules in MN group (89.0% of them were papillary carcinomas - PTC), in 6.4% FLUS nodules (69.2% PTC), and in 10.8% SFN nodules (30.8% PTC). In the UC group all UMRFs occurred more frequently in cancers than in benign lesions. In the FL group only calcifications were found in cancers more frequently - macro and microcalcifications together: 34.6 vs. 11.5% (p = 0.001) and isolated macrocalcifications: 26.0 vs. 6.8% (p = 0.001); the presence of those features increased the basic risk of malignancy in FL more than 2 times. The presence of at least 2 of the following URMFs: hypoechogenicity, solid echostructure, any type of calcifications and suspected shape, additionally improved sensitivity.

CONCLUSIONS

Evaluation of UMRFs in FLs is less effective than in nodules with UC, and its effectiveness decreases parallel to the decrease in percentage of PTCs among malignant neoplasms and to the increase of the percentage of adenomas among benign nodules. The presence of macrocalcifications in such FLs significantly increases the basic risk of malignancy in these nodules.

Malignancy is associated with microcalcification and higher AP/T ratio in ultrasonography, but not with Hashimoto's thyroiditis in histopathology in patients with thyroid nodules evaluated as Bethesda Category III (AUS/FLUS) in cytology

The predictors of malignancy are important for the decision of appropriate management in nodules with atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS). Our aim was to determine the ultrasonographical, clinical, and biochemical predictors of malignancy in these patients. A total of 427 patients with cytologically Bethesda Category III (AUS/FLUS) thyroid nodules were included in this retrospective study. We divided the nodules into two subgroups according to the histopathology as benign and malignant, and compared the preoperative ultrasonographical, clinical, and biochemical findings. In overall, 427 patients with 449 AUS/FLUS nodules who had undergone surgery, the rate of malignancy was 23.4 % (105/449). When evaluated separately, the rate of malignancy was 25.8 % in nodules with AUS (82/318) and 17.6 % in nodules with FLUS (23/131) (p = 0.061). The vast majority of malignant specimens in histopathology consisted of papillary thyroid carcinoma (PTC) (n = 91, 86.7 %). Preoperative ultrasonographic features of 105 malignant nodules in histopathology were compared with the 344 benign nodules in histopathology. Anteroposterior/Transverse (AP/T) ratio was significantly higher in malignant group compared to benign group (p = 0.013). In multiple logistic analysis, we found that higher AP/T ratio and microcalcification were independently associated with malignancy (p < 0.05). The malignancy-associated cut-off value of AP/T ratio at maximum sensitivity and specificity was ≥0.81. We did not find any correlation between malignancy and Hashimoto's thyroiditis in histopathology in multivariate analysis (p > 0.05). In Bethesda Category III nodules with higher AP/T ratio and microcalcification, surgery might be considered as a first therapeutic option instead of repeat fine-needle aspiration biopsy or observation.

Ultrasonographic Differentiation Between Nodular Hyperplasia and Neoplastic Follicular-Patterned Lesions of the Thyroid Gland

We evaluate the gray-scale ultrasonographic characteristics that differentiate between nodular hyperplasia (NH) and neoplastic follicular-patterned lesions (NFPLs) of the thyroid gland. Ultrasonographic features of 750 patients with 832 thyroid nodules (NH, n = 361; or NFPLs, follicular adenoma, n = 123; follicular carcinoma, n = 159; and follicular variant papillary carcinoma, n = 189) were analyzed. Except for echogenicity, over two-thirds of the cases of NH and NFPLs share the ultrasonographic characteristics of solid internal content, a well-defined smooth margin and round-to-ovoid shape. Independent predictors for NH were non-solid internal content (sensitivity 27.1%, specificity 90.2%), isoechogenicity (sensitivity 69.5%, specificity 63.5%) and an ill-defined margin (sensitivity 18.8%, specificity 94.5%). Independent predictors for NFPLs were hypoechogenicity (sensitivity 60.5%, specificity 70.4%), marked hypoechogenicity (sensitivity 2.8%, specificity 99.4%) and taller-than-wide shape (sensitivity 6.6%, specificity 98.1%). Although NH and NFPLs commonly share ultrasonographic characteristics, non-solid internal content and ill-defined margin are specific to NH and marked hypoechogenicity and taller-than-wide shape are specific to NFPLs.

The Diagnostic Performance of Thyroid US in Each Category of the Bethesda System for Reporting Thyroid Cytopathology

We aimed to evaluate the diagnostic performance of thyroid ultrasonography (US) in each category of the Bethesda system and analyze false positive/negative findings using US. This retrospective study included 622 thyroid nodules in 592 patients. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) and accuracy of US in each category of the Bethesda system were evaluated. False positive/negative cases of US were analyzed. Out of the 622 total thyroid FNAs, 179 (28.8%) were malignant. The malignancy rates for the 6 categories were as follows: I (nondiagnostic): 9.7%, II (benign): 2.5%, III (atypia/follicular lesion of undetermined significance): 37.5%, IV (suspicious for follicular neoplasm): 5.7%, V (suspicious for malignancy): 100%, and VI (malignancy): 100%. The accuracies of US for the 6 categories were 92.5%, 95.6%, 70.8%, 94.3%, 95%, and 92.4% in category order. US showed the lowest sensitivity (50%) in Category IV. Category III demonstrated relatively low sensitivity (66.7%) and specificity (73.3%) due to a high incidence of follicular variant of papillary thyroid carcinoma and a low number of category III nodules. The most optimal performance of US was revealed in Category I with 88.9% sensitivity and 92.9% specificity. In 22 US false positive cases, the most frequent finding was associated with marked hypoechogenicity and the least finding was noncircumscribed margin. The most common US features of 19 false negative cases were circumscribed iso or hypoechoic nodules. These results highlight the excellent diagnostic performance of US in category I of the Bethesda system and the lowest sensitivity of US in category IV. Awareness of US interpreters regarding these pitfalls can minimize false positive/negative diagnoses and prevent unnecessary interventions.

Usefulness of NRAS codon 61 mutation analysis and core needle biopsy for the diagnosis of thyroid nodules previously diagnosed as atypia of undetermined significance

A repeat fine needle aspiration (FNA) is recommended for thyroid nodules diagnosed as atypia of undetermined significance (AUS) in a previous cytology. We evaluated the utility of NRAS codon 61 (NRAS61) mutation analysis and core needle biopsy (CNB) for the diagnosis of thyroid nodules previously diagnosed as AUS. This study enrolled 236 patients who underwent both NRAS61 mutation analysis and CNB of thyroid nodules previously diagnosed as AUS at cytology. The NRAS61 mutation was detected in 36 nodules and was more frequently detected in the AUS and follicular neoplasm (FN)/suspicious for follicular neoplasm (SFN) categories, as determined by histological analysis of CNB, than in the benign group (p = 0.005). Sixty-one patients underwent surgery, and 29 nodules were finally diagnosed as malignant after surgery. Among 61 patients who underwent surgery, nodules with the NRAS61 mutation (42-65 %) had a significantly higher malignancy rate than nodules with wild-type NRAS61 (7-37 %, p = 0.038). The association between malignancy and the NRAS61 mutation was significant after adjusting for age, sex, nodule size, and histological diagnosis of CNB (p = 0.01). NRAS61 mutation analysis together with CNB could be helpful for arriving at a clinical decision in patients with thyroid nodules showing AUS in a previous cytology.

Ultrasonography Diagnosis and Imaging-Based Management of Thyroid Nodules: Revised Korean Society of Thyroid Radiology Consensus Statement and Recommendations

The rate of detection of thyroid nodules and carcinomas has increased with the widespread use of ultrasonography (US), which is the mainstay for the detection and risk stratification of thyroid nodules as well as for providing guidance for their biopsy and nonsurgical treatment. The Korean Society of Thyroid Radiology (KSThR) published their first recommendations for the US-based diagnosis and management of thyroid nodules in 2011. These recommendations have been used as the standard guidelines for the past several years in Korea. Lately, the application of US has been further emphasized for the personalized management of patients with thyroid nodules. The Task Force on Thyroid Nodules of the KSThR has revised the recommendations for the ultrasound diagnosis and imaging-based management of thyroid nodules. The review and recommendations in this report have been based on a comprehensive analysis of the current literature and the consensus of experts.

Core Needle Biopsy Is a More Conclusive Follow-up Method Than Repeat Fine Needle Aspiration for Thyroid Nodules with Initially Inconclusive Results: A Systematic Review and Meta-Analysis

Background:

This study investigated the appropriate management of thyroid nodules with prior non-diagnostic or atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) through a systematic review and meta-analysis.

Methods:

This study included 4,235 thyroid nodules from 26 eligible studies. We investigated the conclusive rate of follow-up core needle biopsy (CNB) or repeat fine needle aspiration (rFNA) after initial fine needle aspiration (FNA) with non-diagnostic or AUS/FLUS results. A diagnostic test accuracy (DTA) review was performed to determine the diagnostic role of the follow-up CNB and to calculate the area under the curve (AUC) on the summary receiver operating characteristic (SROC) curve.

Results:

The conclusive rates of follow-up CNB and rFNA after initial FNA were 0.879 (95% confidence interval [CI], 0.801 to 0.929) and 0.684 (95% CI, 0.627 to 0.736), respectively. In comparison of the odds ratios of CNB and rFNA, CNB had more frequent conclusive results than rFNA (odds ratio, 5.707; 95% CI, 2.530 to 12.875). Upon subgroup analysis, follow-up CNB showed a higher conclusive rate than rFNA in both initial non-diagnostic and AUS/FLUS subgroups. In DTA review of followup CNB, the pooled sensitivity and specificity were 0.94 (95% CI, 0.88 to 0.97) and 0.88 (95% CI, 0.84 to 0.91), respectively. The AUC for the SROC curve was 0.981, nearing 1.

Conclusions:

Our results show that CNB has a higher conclusive rate than rFNA when the initial FNA produced inconclusive results. Further prospective studies with more detailed criteria are necessary before follow-up CNB can be applied in daily practice.

2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer

BACKGROUND

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. Since the American Thyroid Association's (ATA's) guidelines for the management of these disorders were revised in 2009, significant scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, researchers, and health policy makers on published evidence relating to the diagnosis and management of thyroid nodules and differentiated thyroid cancer.

METHODS

The specific clinical questions addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of task force members. Task force panel members were educated on knowledge synthesis methods, including electronic database searching, review and selection of relevant citations, and critical appraisal of selected studies. Published English language articles on adults were eligible for inclusion. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations for therapeutic interventions. We developed a similarly formatted system to appraise the quality of such studies and resultant recommendations. The guideline panel had complete editorial independence from the ATA. Competing interests of guideline task force members were regularly updated, managed, and communicated to the ATA and task force members.

RESULTS

The revised guidelines for the management of thyroid nodules include recommendations regarding initial evaluation, clinical and ultrasound criteria for fine-needle aspiration biopsy, interpretation of fine-needle aspiration biopsy results, use of molecular markers, and management of benign thyroid nodules. Recommendations regarding the initial management of thyroid cancer include those relating to screening for thyroid cancer, staging and risk assessment, surgical management, radioiodine remnant ablation and therapy, and thyrotropin suppression therapy using levothyroxine. Recommendations related to long-term management of differentiated thyroid cancer include those related to surveillance for recurrent disease using imaging and serum thyroglobulin, thyroid hormone therapy, management of recurrent and metastatic disease, consideration for clinical trials and targeted therapy, as well as directions for future research.

CONCLUSIONS

We have developed evidence-based recommendations to inform clinical decision-making in the management of thyroid nodules and differentiated thyroid cancer. They represent, in our opinion, contemporary optimal care for patients with these disorders.

Relationship Between Sonographic Characteristics and Afirma Gene Expression Classifier Results in Thyroid Nodules With Indeterminate Fine-Needle Aspiration Cytopathology

OBJECTIVE

The purpose of this article is to investigate whether specific clinical and sonographic characteristics are predictive of a benign Afirma test result.

MATERIALS AND METHODS

We conducted a retrospective study of Afirma gene expression classifier analysis performed in 44 patients with 45 indeterminate thyroid fine-needle aspiration (FNA) cytologic results between March 2013 and April 2014. Of these, 33 of 45 nodules (73.3%) were repeat atypia of undetermined significance (AUS) and follicular lesions of undetermined significance (FLUS), or follicular neoplasm (FN) and suspicious for a follicular neoplasm (SFN) before Afirma testing.

RESULTS

Of the 45 nodules, 21 (46.7%) were cytologically diagnosed as FLUS, 16 (35.6%) were diagnosed as AUS, and eight (17.8%) were diagnosed as FN or SFN. By Afirma testing, 23 of the 45 nodules (51.1%) were benign, 21 (46.7%) were suspicious, and one (2.2%) had nondiagnostic results. The mean (± SD) nodule size was smaller in the Afirma-benign group than in the Afirma-suspicious group (1.8 ± 0.8 cm [95% CI, 1.4-2.1] vs 2.2 ± 0.8 cm [95% CI, 1.8-2.6]; p < 0.035). No sonographic feature was statistically significantly different between the Afirma-benign and -suspicious groups, including nodule solidity (p = 0.225), echogenicity (p = 0.543), calcification (p = 0.542), and hypervascularity (p = 0.976). All nodules were ovoid shaped and had circumscribed margins in both Afirma groups.

CONCLUSION

Smaller nodule size was the only characteristic associated with a benign diagnosis on Afirma testing. Sonographic characteristics are not helpful in cases that had a repeat indeterminate FNA finding before Afirma testing.

Ultrasonographic Findings in Patients with Benign and Malignant Thyroid Nodules who underwent Ultrasound Guided Fine Needle Aspiration Cytology

BACKGROUND

Patients with thyroid nodules represent common problem in daily routine of thyroidologists as well as other medical specialties. Fortunately only small number of thyroid nodules turns out to be malignant. Ultrasound is most frequently used imaging modality in the evaluation of thyroid nodules and certain ultrasonographic features are associated with greater risk for malignancy.

AIM

The aim of our study was to evaluate the diagnostic performance of various ultrasonographic findings regarding thyroid malignancy.

METHODS

Between September 2012 and August 2013 a total of 592 patients with 694 nodules were included in the present study. They were evaluated for thyroid nodules as a part of routine work up at outpatient's unit of Institute of Pathophysiology and Nuclear Medicine, Medical Faculty, UKIM Skopje. In all patients thyroid ultrasound and fine needle aspiration cytology (FNAC) were performed. Surgically were removed 84 nodules and ultrasonography and cytology data were compared to histology results.

RESULTS

From all examined ultrasonographic features, significant association with malignancy has been found for hypoechogenecity, marked central vascularisation, ultrasound suspicious nodules (including at least two suspicious features) and marginal for presence of microcalcifications. Highest sensitivity was obtained for hypoechogenecity, and highest specificity for microcalcifications and marked central vascularisation.

CONCLUSION

Awareness of the suspicious ultrasound features is mandatory in order to optimize diagnostic and therapeutic approach to the vast number of patients with thyroid nodules.