Evaluation Of Indeterminate Thyroid Nodules Research Articles

The application of high-throughput proteomics in cytopathology.

High-throughput genomics and transcriptomics are often applied in routine pathology practice to facilitate cancer diagnosis, assess prognosis, and predict response to therapy. However, the proteins rather than nucleic acids are the functional molecules defining the cellular phenotype in health and disease, whereas genomic profiling cannot evaluate processes such as the RNA splicing or posttranslational modifications and gene expression does not necessarily correlate with protein expression. Proteomic applications have recently advanced, overcoming the issue of low depth, inconsistency, and suboptimal accuracy, also enabling the use of minimal patient-derived specimens. This review aims to present the recent evidence regarding the use of high-throughput proteomics in both exfoliative and fine-needle aspiration cytology. Most studies used mass spectrometry, as this is associated with high depth, sensitivity, and specificity, and aimed to complement the traditional cytomorphologic diagnosis, in addition to identify novel cancer biomarkers. Examples of diagnostic dilemmas subjected to proteomic analysis included the evaluation of indeterminate thyroid nodules or prediction of lymph node metastasis from thyroid cancer, also the differentiation between benign and malignant serous effusions, pancreatic cancer from autoimmune pancreatitis, non-neoplastic from malignant biliary strictures, and benign from malignant salivary gland tumors. A few cancer biomarkers-related to diverse cancers involving the breast, thyroid, bladder, lung, serous cavities, salivary glands, and bone marrow-were also discovered. Notably, residual liquid-based cytology samples were suitable for satisfactory and reproducible proteomic analysis. Proteomics could become another routine pathology platform in the near future, potentially by using validated multi-omics protocols.

Diagnostic reliability of elastography in thyroid nodules reported as indeterminate at prior fine-needle aspiration cytology (FNAC): a systematic review and Bayesian meta-analysis.

To assess the diagnostic yields of elastography in thyroid nodules reported as indeterminate in FNAC according to guidelines. Databases of Medline, Embase, and Cochrane Central were searched till 31 October 2019. Two different reviewers check the studies and extracted the data. The diagnostic accuracy and yield were quantitatively synthesized using Bayesian bivariate model in R. Twenty studies with 1734 indeterminate thyroid nodules undergoing elastography were included. The summary estimates of sensitivity and specificity were 0.766 (95% credible interval (CrI), 0.686-0.835) and 0.867 (95% CrI, 0.780-0.931), respectively. The summary estimate for diagnostic odds ratio (DOR) was 25.9 (95% CrI, 12.8-46.2). Summary receiver operating characteristic plots for elastography showed a right-diagonal curvilinear relationship, suggesting a trade-off between sensitivity and specificity, and the estimate of area under curve (AUC)was 0.743. The summary estimates for positive and negative likelihood ratios were 6.6 (95% CrI, 4.2-11.3) and 0.27 (95% CrI, 0.21-0.36), respectively. Elastography had fair diagnostic yields in indeterminate thyroid nodules. Shear wave elastography and strain ratio elastography could be more efficient in diagnosis and should evolve in the next years while combing elastography with ultrasound would contribute more to sensitivity and specificity currently. • Elastography has fair diagnostic yields in indeterminate thyroid nodules. • Shear wave elastography and strain ratio elastography are more efficient than real-time elastography. • Combining elastography and other ultrasound techniques improves evaluation of indeterminate thyroid nodules.

Utility of a multigene testing for preoperative evaluation of indeterminate thyroid nodules: A prospective blinded single center study in China.

BackgroundThyroid nodules are highly prevalent, with fine‐needle aspiration (FNA) commonly used as the standard preoperative tool for their diagnosis. However, the method classifies some of the samples as indeterminate, leading to unnecessary surgery. In this study, we evaluated the value of next‐generation sequencing (NGS) for cancer diagnosis in indeterminate thyroid nodules.Materials and methodsWe performed a prospective, blinded cohort study on 189 patients, with 196 Bethesda III/IV nodules. Specifically, we analyzed DNA mutations and RNA fusions across the FNA samples using NGS, then reviewed follow‐up reports from 84 nodules following definitive surgery, to determine the assay performance.ResultsEnough DNA and RNA were obtained in 188 nodules, revealing mutations or fusions in 34.6% of them. The most frequently mutated genes were RAS, followed by BRAF V600E. Based on surgical pathology, 39% (33/84) and 4.8% (4/84) of the nodules were malignant and intermediate, respectively. According to the risk stratification criteria, 28 cases were categorized High‐Risk group, all of the resected nodules (n = 20) were malignant. Twenty‐four thyroid nodules were in the Low‐Risk group, 28.6% (4/14) surgically removed nodules were malignant. In the Benign‐Like category, 18.0% (9/50) were malignant. Five out of 13 nodules with benign mutations were resected, including SPOP, EZH1, and ZNF148, all of them were benign. If genetic alterations annotated with High‐Risk or Low‐Risk was considered as positive, and negative if Benign‐Like. Multigene testing revealed sensitivity, specificity, positive predictive values (PPV), and negative predictive value (NPV) of 73%, 80%, 71%, and 82%, respectively. In addition, if four intermediate nodules were counted as malignant, the PPV and NPV were 71% and 74%.ConclusionOur results allow for further stratification of Bethesda III/IV thyroid nodules based on the risk of their malignancy. SPOP, EZH1, and ZNF148 mutations may be used as benign markers.

Utility of Afirma Gene Expression Classifier for Evaluation of Indeterminate Thyroid Nodules and Correlation with Ultrasound Risk Assessment: Single Institutional Experience

Objective: We assessed our experience with Afirma gene expression classifier (GEC) combined with sono-graphic risk assessment, using both the American Thyroid Association (ATA) and the Thyroid Imaging Reporting and Data System (TI-RADS) in evaluating indeterminate thyroid nodules. Methods: We identified 98 patients with 101 nodules who had a second fine needle aspiration biopsy (FNA) between January 1, 2014, and September 30, 2017, and sent to Veracyte for cytopathology and subsequent Afirma GEC testing. A second FNA biopsy was performed if the initial cytopathology was either Bethesda III or IV (n = 94) or nondiagnostic (n = 7). We correlated cytopathology, histopathology, and Afirma GEC results with sonographic risk assessment using both the ATA system and TI-RADS. Results: The mean age of the cohort was 57.4 ± 12.3 years; 84% women and 60% white. Repeat FNA was benign in 51 of 101 nodules, and of the remaining 50 nodules, 18 (36%) were GEC-benign and 32 (64%) GEC-suspicious. Eighteen of the 32 GEC-suspicious nodules underwent surgery with the following results: 7 benign (39%), 1 follicular thyroid carcinoma (6%), 6 follicular variant of papillary thyroid cancer (33%), and 4 noninvasive follicular tumor with papillary-like nuclear features (22%). The malignancy rate among the surgical cohort was 39% (without noninvasive follicular tumor with papillary-like nuclear features [NIFTP]) and 61% (with NIFTP) and about 50% and 20% of this group scored in the high suspicion category by ATA and TR5 by TI-RADS, respectively. Conclusion: Afirma GEC was useful in avoiding surgery in one-third of indeterminate nodules and performed similarly to ATA and TI-RADS. However, the use of echogenicity in scoring may underestimate the risk of malignancy in patients with indeterminate nodules. Abbreviations: ATA = American Thyroid Association; AUS = Atypia of Undetermined Significance; FLUS = Follicular Lesion of Undetermined Significance; FN = follicular neoplasm; FNA = fine needle aspiration; FTC = follicular thyroid cancer; FVPTC = follicular variant of papillary thyroid cancer; GEC = Gene Expression Classifier; ND = nondiagnostic; NIFTP = noninvasive follicular tumor with papillary-like nuclear features; TI-RADS = Thyroid Imaging Reporting and Data System; TR = TI-RADS.

Molecular markers for the classification of cytologically indeterminate thyroid nodules.

The diagnosis of indeterminate lesions of the thyroid is a challenge in cytopathology practice. Indeed, up to 30% of cases lack the morphological features needed to provide definitive classification. Molecular tests have been developed to assist in the diagnosis of these indeterminate cases. The first studies dealing with the preoperative molecular evaluation of FNA samples focused on the analysis of BRAFV600E or on the combined evaluation of two or three genetic alterations. The sensitivity of molecular testing was then improved through the introduction of gene panels, which became available for clinical use in the late 2000s. Two different categories of molecular tests have been developed, the 'rule-out' methods, which aim to reduce the avoidable treatment of benign nodules, and the 'rule-in' tests that have the purpose to optimize surgical management. The genetic evaluation of indeterminate thyroid nodules is predicted to improve patient care, particularly if molecular tests are used appropriately and with the awareness of their advantages and weaknesses. The main disadvantage of these tests is the cost, which makes them rarely used in Europe. To overcome this limitation, customized panels have been set up, which are able to detect the most frequent genetic alterations of thyroid cancer. In the present review, the most recent available versions of commercial molecular tests and of custom, non-commercial panels are described. Their characteristics and accuracy in the differential diagnosis of indeterminate nodules, namely Bethesda classes III (Atypical follicular lesion of undetermined significance, AUS/FLUS) and IV (Suspicious for follicular neoplasm, FN/SFN) are fully analyzed and discussed.

Mutational Analysis Is Useful in the Evaluation of Indeterminate Thyroid Nodules

Mutational Analysis Is Useful in the Evaluation of Indeterminate Thyroid Nodules

Clinical performance of a next-generation sequencing assay (ThyroSeq v2) in the evaluation of indeterminate thyroid nodules

Molecular testing with the Thyroseq v2 next generation sequencing panel ("Thyroseq") is used to estimate the risk of cancer in indeterminate thyroid nodules. We analyzed 156 indeterminate thyroid nodules evaluated with Thyroseq, across 3 institutions. Thyroseq data and surgical pathology were matched via pathologic re-review. A result was considered Thyroseq positive if molecular alterations were annotated on the report with malignancy probability >30%. Performance characteristics were estimated using Bayes theorem. The Thyroseq-negative call rate was 65% (102/156). On surgical pathology, 16% (10/63) of nodules were malignant. The positive predictive value of a Thyroseq-positive result was 22% (8/37; if 2 noninvasive follicular thyroid neoplasm with papillary-like nuclear features are counted as malignant, 27%, 10/37). There was 1 false-negative result (negative predictive value 96%, 22/23). The most common mutation was NRAS (19/37) with a positive predictive value of 7% (1/15). The positive predictive value of all RAS mutations (HRAS, KRAS, NRAS) was 9% (2/22). The second most common mutation, BRAF V600E, had positive predictive value of 100% (3/3). We report an external analysis of Thyroseq performance in the evaluation of indeterminate thyroid nodules. These data indicate that Thyroseq is likely to offer high negative predictive value but low positive predictive value. Many genetic alterations appear to be nonspecific for malignancy, and positive results should be interpreted with caution. These findings have implications for the management of indeterminate thyroid nodules profiled with Thyroseq.

Retrospective cytological evaluation of indeterminate thyroid nodules according to the British Thyroid Association 2014 classification and comparison of clinical evaluation and outcomes.

The cytology of 130 indeterminate nodules (Thy 3) was retrospectively reviewed according to the British Thyroid Association 2014 classification. Nodules were divided into Thy 3a (atypical features) and Thy 3f (follicular lesion) categories. Histology was available as a reference for 97 nodules. Pre-surgical evaluations comprised biochemical tests, color-Doppler ultrasonography (US), semi-quantitative elastography-US (USE), contrast-enhanced US (CEUS), and mutation analysis from cytological slides. Thyroid malignancy was the final diagnosis for 19% of surgically-treated nodules. No statistically significant difference in the risk of malignancy was found between Thy 3a (26%) and Thy 3f (14%) nodules. Histology of the Thy 3a and Thy 3f nodules showed a higher incidence of Hurtle cell adenomas in Thy 3f (29%) than in Thy 3a (3%) nodules (P=0.01). The only pre-surgical difference concerned the BRAF V600E mutation, which was positive in some Thy 3a but not in any Thy 3f nodules (P=0.04). Receiver-operating characteristic (ROC) analysis was used to obtain cut-off values from US (score), USE (ELX 2/1 strain index), and CEUS (time-to-peak index and peak index) data. The cut-off values were similar for Thy 3a and Thy 3f nodules. Data showed that malignancy can be suspected if the US score is >2, ELX 1/2 strain index >1, time-to-peak index >1, and peak index <1. In a sub-group of 24 revised nodules (12 Thy 3a and 12 Thy 3f) with histology as a reference, the diagnostic power of cumulative pre-surgical analysis by means of US, USE, and CEUS showed high positive and negative predictive values (83% and 100%, respectively) for the presence of malignancy in Thy 3a and Thy 3f nodules. In conclusion, in our series of revised Thy 3 nodules, malignancy was low and displayed no significant differences between Thy 3a and Thy 3f categories. The use of cut-offs based on histology as a reference could reduce surgery. Our data support the conviction that, in mutation-negative Thy 3a and Thy 3f nodules, observation should be the first choice when not all instrumental results are suspect.

Utility of Diagnostic Molecular Markers for Evaluation of Indeterminate Thyroid Nodules.

Utility of Diagnostic Molecular Markers for Evaluation of Indeterminate Thyroid Nodules.

Ultrasound elastography in the diagnostic evaluation of indeterminate thyroid nodules

ObjectiveTo assess the accuracy of US-elastography in the evaluation of indeterminate thyroid nodules, using the cytological/histopathological analysis as the reference. Patients and methodsFifty patients with 73 indeterminate thyroid nodules were enrolled in this prospective study. They were examined using US features and elastography scoring according to Rago criteria; then, fine-needle or postoperative biopsy was taken and diagnosis was made. ResultsFifty patients with 73 indeterminate thyroid nodules were included, 16 nodules were malignant and 57 were benign. On US elastography, all 57 nodules diagnosed as benign had a score of 1–3, while 15 of 16 (93.75%) diagnosed as carcinoma had a score of 4–5, with 93.3% sensitivity, 100% specificity and 97.8% accuracy. Combined US findings with elastography revealed that hypoechogenicity/score 4–5 was most predictive of malignancy with sensitivity 80%, specificity 100%; and accuracy 93.4%. The strain ratio cutoff value for malignant nodules was determined as 2.3. Five nodules out of sixteen had SR between 2.31 and 4 (sensitivity 96% and specificity 83%). ConclusionThyroid nodules with suspicious US criteria can be evaluated by US elastography that seems to be a useful addition for the assessment of such indeterminate nodules. It may reduce FNAC or select a nodule for aspiration.

Is18F-Fluorodeoxyglucose–PET/CT Useful for the Presurgical Characterization of Thyroid Nodules with Indeterminate Fine Needle Aspiration Cytology?

Thyroid nodules found incidentally on (18)F-fluorodeoxyglucose-positron emission tomography (FDG-PET) have been shown to be malignant in 30%-50% of cases. The American Thyroid Association recommends performing fine needle aspiration cytology (FNAC) for thyroid nodules showing FDG uptake. On the other hand, the role of FDG-PET in characterizing thyroid nodules with indeterminate cytology before surgery is not clear. The goal of this study was to evaluate the role of FDG-PET/computed tomography (CT) in predicting malignancy of thyroid nodules with indeterminate FNAC and to correlate FDG uptake with pathological and ultrasonographic (US) features. Between November 2006 and October 2009, 55 patients (42 women, mean age: 50 years) planned for surgery for 56 thyroid nodules with indeterminate FNAC were prospectively included and considered for analysis. All patients underwent presurgical FDG-PET/CT (Siemens Biograph, mean FDG injected activity: 165 MBq) and neck US. Pathology of the corresponding surgical specimen was the gold standard for statistical analysis. At pathology 34 nodules were benign, 10 were malignant (7 papillary and 3 follicular carcinomas), and 12 were tumors of uncertain malignant potential (TUMP). The median size of the thyroid nodules was 21 mm (range: 10-57). Sensitivity, specificity, positive (PPV), and negative predictive (NPV) values of FDG-PET in detecting cancer/TUMP were 77%, 62%, 57%, and 81%, respectively. In multivariate analysis, cellular atypia was the only factor predictive of FDG uptake (p<0.001). Hurthle cells and poorly differentiated components were independent predictive factors of high (≥5) SUV Max (p=0.02 and p=0.02). Sensitivity, specificity, PPV, and NPV of US in detecting cancer/TUMP were 82%, 47%, 50%, and 80%, respectively. In multivariate analysis, hypervascularization was correlated with malignancy/TUMP (p=0.007) and cystic features were correlated with benignity (p=0.03). Adding FDG-PET findings to neck US provided no diagnostic benefit. The sensitivity and specificity of FDG-PET in the presurgical evaluation of indeterminate thyroid nodules are too low to recommend FDG-PET routinely.