Stepwise analysis of thyroid diagnostic modalities with genomic imprinting detection.

BACKGROUND: The current preoperative malignancy risk evaluation for thyroid nodules involves stepwise diagnostic modalities including ultrasonography, thyroid function serology and fine-needle aspiration (FNA) cytopathology, respectively. We aimed to substantiate the stepwise contributions of each diagnostic step and additionally investigate the diagnostic significance of quantitative chromogenic imprinted gene in-situ hybridization (QCIGISH)-an adjunctive molecular test based on epigenetic imprinting alterations. METHODS: A total of 114 cytopathologically-diagnosed and histopathologically-confirmed thyroid nodules with complete ultrasonographic and serological examination records were evaluated using QCIGISH in the study. Logistic regression models for thyroid malignancy prediction were developed with the stepwise addition of each diagnostic modality and the contribution of each step evaluated in terms of discrimination performance and goodness-of-fit. RESULTS: From the baseline model using ultrasonography [area under the receiver operating characteristics curve (AUROC): 0.79; 95% confidence interval (CI): 0.71-0.86], significant improvements in thyroid malignancy discrimination were observed with the stepwise addition of thyroid function serology (AUROC: 0.82; 95% CI: 0.74-0.90; P=0.23) and FNA cytopathology (AUROC: 0.88; 95% CI: 0.81-0.94; P=0.02), respectively. The inclusion of QCIGISH as an adjunctive molecular test further advanced the preceding model's diagnostic performance (AUROC: 0.95; 95% CI: 0.91-1.00, P=0.007). CONCLUSIONS: Our study demonstrated the significant stepwise diagnostic contributions of standard clinical assessments in the malignancy risk stratification of thyroid nodules. However, the addition of molecular imprinting detection further enabled a more accurate and definitive preoperative evaluation especially for morphologically indeterminate thyroid nodules and cases with potentially discordant results among standard modalities.

High Diagnostic Accuracy of Epigenetic Imprinting Biomarkers in Thyroid Nodules.

PURPOSE: To explore the novel diagnostic value of epigenetic imprinting biomarkers in thyroid nodules. PATIENTS AND METHODS: A total of 550 patients with fine-needle aspiration (FNA)-evaluated and histopathologically confirmed thyroid nodules were consecutively recruited from eight medical centers. Quantitative chromogenic imprinted gene in situ hybridization (QCIGISH) was used to assess the allelic expression of imprinted genes SNRPN and HM13, on the basis of which a diagnostic grading model for thyroid nodules was developed. The model was retrospectively trained on 124 postsurgical thyroid samples, optimized on 32 presurgical FNA samples, and prospectively validated on 394 presurgical FNA samples. Blinded central review-based cytopathologic and histopathologic diagnoses were used as the reference standard. RESULTS: For thyroid malignancy, the QCIGISH test achieved an overall diagnostic sensitivity of 100% (277/277), a specificity of 91.5% (107/117; 95% CI, 86.4 to 96.5), a positive predictive value (PPV) of 96.5% (95% CI, 94.4 to 98.6), and a negative predictive value (NPV) of 100% in the prospective validation, with a diagnostic accuracy of 97.5% (384/394; 95% CI, 95.9 to 99.0). QCIGISH demonstrated a PPV of 97.8% (95% CI, 94.7 to 100) and NPV of 100%, with a diagnostic accuracy of 98.2% (111/113; 95% CI, 95.8 to 100), for indeterminate Bethesda III-V thyroid nodules. QCIGISH demonstrated a PPV of 96.6% (95% CI, 91.9 to 100) and a NPV of 100%, with a diagnostic accuracy of 97.5% (79/81; 95% CI, 94.2 to 100), for Bethesda III-IV. For Bethesda VI, QCIGISH showed a 100% (184/184) accuracy. CONCLUSION: This imprinting biomarker-based test can effectively distinguish malignant from benign thyroid nodules. The high PPV and NPV make the test both an excellent rule-in and rule-out diagnostic tool. With such a diagnostic performance and its technical simplicity, this novel thyroid molecular test is clinically widely applicable.

BRAFV600E mutation combined with American College of Radiology thyroid imaging report and data system significantly changes surgical resection rate and risk of malignancy in thyroid cytopathology practice.

BACKGROUND: Ultrasonography patterns and molecular testing may assist in stratifying the malignancy risk of indeterminate cytology diagnosis. The purpose of this study was to assess the value of fine needle aspiration (FNA) cytology in combination with American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) and BRAFV600E mutation in differentiating high-risk thyroid nodules. METHODS: From February 2010 to February 2014, 2,643 consecutive thyroid nodules from 2,399 patients (688 men and 1,711 women; mean age, 44.3±12.5 years) who underwent preoperative FNA biopsies were enrolled. The Jiangsu Institute of Nuclear Medicine has adopted TI-RADS stratification and BRAFV600E mutation analysis as a routine procedure to assist in evaluating FNA cytopathology since January 2016. From February 2017 to July 2018, 1,905 thyroid nodules of 1,837 patients (501 men and 1,336 women, 49.5±12.8 years) who underwent preoperative ultrasound-guided FNA biopsies with BRAFV600E mutation analysis and ACR TI-RADS grading data available were enrolled for comparison in this study. RESULTS: The cancer risk in nodules with BRAFV600E mutation was 99.7% (905/908) according to the histological findings. The risk of malignancy (ROM) was found to increase with advancing ACR TI-RADS category. High-risk ultrasound features (TI-RADS 5) did show a good performance in predicting malignancy (98.1%). The combination of TI-RADS 5 and BRAFV600E mutation reached the best diagnostic efficiency [sensitivity 97.7%, specificity 94.8%, positive predictive value (PPV) 99.6%]. It is apparent that after the implementation of ACR TI-RADS and the BRAFV600E mutation analysis, the resection rates (RRs) of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) I and III categories showed significant decreases (39.1% vs. 21.6% and 36.1% vs. 16.7%, respectively). In contrast, the risks of malignancy of TBSRTC I and III categories indicated substantial increases (41.5% vs. 80.0% and 34.6% vs. 50.0%, respectively). The ROM of thyroid nodules with nondiagnostic (ND, I) category showed the most significant increase of 41.5% to 80.0%. CONCLUSIONS: ACR TI-RADS, together with BRAFV600E mutation and cytological diagnoses, can assist in improving the prediction of malignancy of thyroid nodules, especially in the TBSRTC I and III categories.

Novel visualized quantitative epigenetic imprinted gene biomarkers diagnose the malignancy of ten cancer types.

BACKGROUND: Epigenetic alterations are involved in most cancers, but its application in cancer diagnosis is still limited. More practical and intuitive methods to detect the aberrant expressions from clinical samples using highly sensitive biomarkers are needed. In this study, we developed a novel approach in identifying, visualizing, and quantifying the biallelic and multiallelic expressions of an imprinted gene panel associated with cancer status. We evaluated the normal and aberrant expressions measured using the imprinted gene panel to formulate diagnostic models which could accurately distinguish the imprinting differences of normal and benign cases from cancerous tissues for each of the ten cancer types. RESULTS: The Quantitative Chromogenic Imprinted Gene In Situ Hybridization (QCIGISH) method developed from a 1013-case study which provides a visual and quantitative analysis of non-coding RNA allelic expressions identified the guanine nucleotide-binding protein, alpha-stimulating complex locus (GNAS), growth factor receptor-bound protein (GRB10), and small nuclear ribonucleoprotein polypeptide N (SNRPN) out of five tested imprinted genes as efficient epigenetic biomarkers for the early-stage detection of ten cancer types. A binary algorithm developed for cancer diagnosis showed that elevated biallelic expression (BAE), multiallelic expression (MAE), and total expression (TE) measurements for the imprinted gene panel were associated with cell carcinogenesis, with the formulated diagnostic models achieving consistently high sensitivities (91-98%) and specificities (86-98%) across the different cancer types. CONCLUSIONS: The QCIGISH method provides an innovative way to visually assess and quantitatively analyze individual cells for cancer potential extending from hyperplasia and dysplasia until carcinoma in situ and invasion, which effectively supplements standard clinical cytologic and histopathologic diagnosis for early cancer detection. In addition, the diagnostic models developed from the BAE, MAE, and TE measurements of the imprinted gene panel GNAS, GRB10, and SNRPN could provide important predictive information which are useful in early-stage cancer detection and personalized cancer management.

American College of Radiology thyroid imaging report and data system combined with K-RAS mutation improves the management of cytologically indeterminate thyroid nodules.

We investigated whether use of American College of Radiology thyroid imaging report and data system (ACR TIRADS) in combination with K-RAS mutation status may facilitate risk stratification of patients with cytological Bethesda Category III and IV thyroid nodules. Ultrasonographic, cytological, and histopathological diagnoses were retrospectively correlated with K-RAS mutation status in a series of 43 cytologically indeterminate thyroid nodules (CITNs) that were referred for surgical excision. K-RAS mutations were detected in 8/43 (18.6%) fine-needle aspiration (FNA) samples as against 11/43 (25.6%) surgical specimens. ACR TIRADS level (TR) TR3 lesions had a malignancy risk of 40%; the K-RAS mutation rate in FNA samples and surgical specimens of category TR3 lesions was 40% and 60%, respectively. K-RAS mutation-positive malignancy was significantly more frequently detected in follicular neoplasm/suspicious for follicular neoplasm (FN/SFN) lesions than that in atypia or follicular lesion of undetermined significance (AUS/FLUS) (P<0.01). Combined use of ACR TIRADS (TR5 as the diagnostic threshold) and K-RAS mutation status helped identify 83.3% (10/12) malignant nodules (58.6% specificity, 45.5% positive predictive value, 89.5% negative predictive value, and 65.9% accuracy). CITNs with ACR TIRADS category TR3 showed an unexpectedly high risk of malignancy. K-RAS mutation-positive FN/SFN nodules have a 50% risk of malignancy and surgery should be recommended. Combined use of ACR TIRADS and K-RAS mutation may facilitate risk-stratification of patients with CITNs. The high negative predictive value (NPV) for malignancy seems sufficient to allow conservative management of patients with active surveillance.

Echogenic foci with comet-tail artifact in resected thyroid nodules: Not an absolute predictor of benign disease.

The purpose of this study was to evaluate the frequency of echogenic foci with comet-tail artifact in histologically proven thyroid nodules, and to determine the types of echogenic foci with comet-tail artifact that are associated with malignancy. We retrospectively analyzed the sonographic findings of echogenic foci with comet-tail artifact, present in thyroid nodules in 63 patients who underwent surgery for thyroid nodules at our institution between January 2016 and September 2016. The sonographic findings (appearance and background of echogenic foci, shape of comet-tail artifact) in benign and malignant nodules were compared. Seventy-one (7.4%) nodules with ultrasound finding of echogenic foci with comet-tail artifact were encountered in 962 thyroid nodules of 556 patients; 25 of these were benign, and 46 were malignant. Among the echogenic foci with comet-tail artifact categories, those (11/11, 100%) freely distributed in cystic components were all in benign nodules, whereas those (48/67, 71.6%) any part of echogenic foci or comet-tail artifact associated with solid components, were more common in malignant nodules (P < 0.001). There was no statistically significant difference in the appearance of echogenic foci and the shape of comet-tail between the benign and malignant nodules (P = 0.139, P = 0.626, respectively). Echogenic foci with comet-tail artifact freely distributed in cystic component may predict a benign nodule; those associated with solid components cannot be considered a benign finding.

Serum thyroglobulin or thyroglobulin in fine-needle aspiration washout of metastatic lymph nodes: which one should we have confidence in for the surveillance of thyroid carcinoma?

BACKGROUND: The objective of this study was to evaluate the diagnostic performance of serum thyroglobulin (S-Tg), thyroglobulin in fine-needle aspiration washout (FNA-Tg) and fine-needle aspiration cytology (FNAC) in the detection of lateral metastatic lymph nodes (LNs) in patients with thyroid carcinoma. METHODS: The study included 19 lateral metastatic LNs from 19 patients with thyroid carcinoma who underwent FNAC for the suspicion of metastatic disease on ultrasonogrphy (US). The S-Tg, FNA-Tg, FNAC, and histopathological results were correlated. RESULTS: Compared with S-Tg, both FNAC and FNA-Tg showed higher sensitivity (89.5%, 89.5% versus 68.4%, respectively) and accuracy (89.5%, 89.5% versus 68.4%, respectively). The combined use of FNAC and FNA-Tg or FNAC and S-Tg showed superior diagnostic power. CONCLUSIONS: S-Tg measurement is a less reliable method for follow-up in patients with thyroid carcinoma in comparison with FNA-Tg. For patients with negative S-Tg but suspicious features in US, FNAC combined with FNA-Tg is strongly recommended to confirm the diagnosis.

Classifier Model Based on Machine Learning Algorithms: Application to Differential Diagnosis of Suspicious Thyroid Nodules via Sonography.

OBJECTIVE: The purpose of this article is to construct classifier models using machine learning algorithms and to evaluate their diagnostic performances for differentiating malignant from benign thyroid nodules. MATERIALS AND METHODS: This study included 970 histopathologically proven thyroid nodules in 970 patients. Two radiologists retrospectively reviewed ultrasound images, and nodules were graded according to a five-tier sonographic scoring system. Statistically significant variables based on an experienced radiologist's observations were obtained with attribute optimization using fivefold cross-validation and applied as the input nodes to build models for predicting malignancy of nodules. The performances of the machine learning algorithms and radiologists were compared using ROC curve analysis. RESULTS: Diagnosis by the experienced radiologist achieved the highest predictive accuracy of 88.66% with a specificity of 85.33%, whereas the radial basis function (RBF)-neural network (NN) achieved the highest sensitivity of 92.31%. The AUC value for diagnosis by the experienced radiologist (AUC = 0.9135) was greater than those for diagnosis by the less experienced radiologist, the naïve Bayes classifier, the support vector machine, and the RBF-NN (AUC = 0.8492, 0.8811, 0.9033, and 0.9103, respectively; p < 0.05). CONCLUSION: The machine learning algorithms underperformed with respect to the experienced radiologist's readings used to construct them, and the RBF-NN outperformed the other machine learning algorithm models.

Ultrasonographic appearance of focal Hashimoto's thyroiditis: A single institution experience.

The purpose of this study was to determine the ultrasonographic (US) appearance of focal Hashimoto's thyroiditis (FHT). Thirty-seven FHT patients and 60 consecutive patients with 60 papillary thyroid carcinomas (PTC) that were confirmed by cytology or histopathology between January 2011 and December 2013 were analyzed. Using the results of color Doppler imaging, US findings were retrospectively reviewed. Inter-group differences in size, internal content, echogenicity, echo texture, shape, boundary, margin, calcifications, fine echogenic septa, and blood flow were statistically assessed. The US appearances of the FHTs examined were: solid (100%), hypoechoic (97%), heterogeneous (68%), ovoid-to-round shape (73%), well-defined boundary (95%), smooth margin (89%), and hypervascular (46%). Ovoid-to-round shape, well-defined boundary, fine echogenic septa, and hypervascularity were significantly more prevalent for FHTs than for PTCs (p < 0.05). Ovoid-to-round shape and fine echogenic septa have a higher specificity and positive predictive value. FHTs show a spectrum of US appearances, making FHT diagnosis cumbersome. Fine echogenic septa are highly specific for FHT. Ovoid-to-round shape, well-defined boundary and hypervascularity may possibly be associated with FHT.

Ultrasound-guided fine-needle aspiration for solid thyroid nodules larger than 10 mm: correlation between sonographic characteristics at the needle tip and nondiagnostic results.

The objective of this study was to investigate the effect of the ultrasonographic (US) characteristics and ultrasound elastography (UE) patterns on the probability of a nondiagnostic result when performing ultrasound-guided fine-needle aspiration (UG-FNA) cytological sampling of solid thyroid nodules larger than 10 mm, to determine the efficacy of needle tip localization in UG-FNA. We retrospectively reviewed the cytological results of 710 samples from 355 patients. We compared the US characteristics and UE patterns between nodules with nondiagnostic and diagnostic results, using univariate and multivariate analyses. Among the 710 samples, 81 samples (11.4 %) from 41 patients had nondiagnostic results. According to multivariate analysis, the combinations of hypoechogenicity with avascularity [odds ratio (OR) = 2.42; 95 % confidence interval (CI) 1.37-3.72; p < 0.05], hypoechogenicity with the "hard pattern" (OR = 2.12; 95 % CI 1.58-4.59; p < 0.05), and hypoechogenicity with avascularity and the hard pattern (OR = 2.61; 95 % CI 1.40-5.21; p < 0.05) were risk factors that increased the incidence of nondiagnostic results in UG-FNA. UG-FNA was more likely to yield nondiagnostic results when the needle tip sampling region displayed hypoechogenicity and avascularity in US and the hard pattern in UE.

Conventional ultrasonography and real time ultrasound elastography in the differential diagnosis of degenerating cystic thyroid nodules mimicking malignancy and papillary thyroid carcinomas.

BACKGROUND: To evaluate the diagnostic utility of conventional ultrasonography and real time ultrasound elastography in differentiating degenerating cystic thyroid nodules mimicking malignancy from papillary thyroid carcinoma. METHODS: We retrospectively analyzed conventional ultrasonographic and elastographic characteristics of 19 degenerating cystic thyroid nodules mimicking malignancy in 19 patients, with 30 surgically confirmed PTCs as controls. Based on size, the nodules had been grouped into less than 10mm (group A) and greater than 10 mm (group B). We evaluated conventional parameters and elasticity pattern. Color-scaled elastograms were graded as to stiffness of nodules using an elasticity pattern from I (soft) to IV (stiff). RESULTS: Degenerating cystic thyroid nodules were similar to PTCs in conventional ultrasonographic findings, but the former frequently showed oval to round in shape (group A, 69.2% vs 18.8%, P=0.017; group B, 66.7% vs 7.14%, P=0.017) and punctuate hyperechoic foci (group A, 61.5% vs 0, P<0.001; group B, 50% vs 0, P<0.001). On real time ultrasound elastography, 7 of 13 degenerating cystic thyroid nodules in group A were pattern I, 5 were pattern II, 1 was pattern III. One degenerating cystic thyroid nodule in group B was pattern II, 5 were pattern III. The area under the curve for elastography was 0.98 in group A (sensitivity 92.3%, specificity 100%, P = 0.002), and 0.88 in group B (sensitivity 16.7%, specificity 100%, P = 0.014). CONCLUSIONS: As a dependable imaging technique, elastography helps increase the performance in differential diagnosis of degenerating cystic thyroid nodule and malignancy.