Differentiation Of Malignant Thyroid Nodules Research Articles

The usefulness of [99mTc]MIBI scintigraphy in the diagnostic algorithm of ultrasonographical suspected thyroid nodules by using EU-TIRADS criteria

Background: Although not yet involved in the algorithm of thyroid nodules, 99mTc-methoxy-isobutyl-isonitrile ([99mTc]MIBI) scintigraphy may help in the individual diagnostic workup of a thyroid patient, especially where indeterminate fine needle aspiration biopsy (FNAB) is present. The aim of this study was to evaluate the usefulness of [99mTc]MIBI thyroid scintigraphy in the diagnostic algorithm of thyroid nodules, particularly in ultrasound EU-TIRADS 4 or 5 lesions, that cytologically were either indeterminate or benign. Material and m ethods: A retrospective randomized study, including 42 thyroid patients, with mean age 47 ± 17 years, was conducted. [99mTc]MIBI scan was compared with ultrasound (US) EU-TIRADS criteria, pertechnetate scan, FNAB and histopathological findings for the differentiation of malignant thyroid nodules from benign lesions. Results: The US mainly detected hypoechoic inhomogeneous presentation of the thyroid nodules (35/42, 83.33%), 4 cases with isoechoic nodules and 2 cases presented with hyperechoic thyroid nodules. Histopathology revealed malignancy in 15/42 (35.71%), while all other patients 27/42 (64.29%) were benign. Visual analysis score showed that patients scored with 1+ and 2+ were statistically significant to be benign, while 13 vs. 10 pts that were visual score 3+ were malignant vs. benign (p > 0.05). Sensitivity was 100%, while specificity was very low 22.22%, PPV was 41.67%. Conclusions: Even [99mTc]MIBI scan is not routinely used as a daily practice diagnostic tool of thyroid nodules, we will further apply it on a larger group of patients and try to quantify the uptake of the radiotracer to see whether it will help in the diagnostic algorithm of thyroid nodules.

Strain Elastography as a Valuable Diagnosis Tool in Intermediate Cytology (Bethesda III) Thyroid Nodules.

Fine needle aspiration (FNA) is considered the gold standard in the diagnostic of thyroid nodules. Using the recommended BETHESDA reporting system, up to 20% of results are classified as intermediate cytology. As there is no consensus whether ultrasound evaluation, lobectomy or surgery is the best treatment option, intermediate cytology results are considered a grey zone of the FNA. The main aim of our study was to evaluate the performance of combined advanced ultrasound techniques in the process of diagnosis and evaluation of the intermediate cytology cases after FNA. We evaluated 54 consecutive cases with intermediate cytology on FNA, using conventional B-mode ultrasound (2B), and strain elastography, using a linear multifrequency 6–13 MHz linear probe (Hitachi Prerius Machine, Hitachi Inc, Japan). All nodules were classified with our Thyroid Imaging Report and Data System (TI-RADS) proposed model, considering: vertical appearance, with antero-posterior diameter bigger than the transvers diameter, the so called taller than wide shape, irregular borders, intranodular inhomogeneity, marked hypoecogenicity, micro calcifications, the presence of suspect lymph nodes, and increased stiffness as suspicious for malignancy. The classification outcomes were compared with the pathology results, considered the gold standard diagnosis. The prevalence of cancer was 28.8%, with 13/45 cases having a clear diagnostic of cancer. Six cases were diagnosed with borderline follicular neoplasia, a category with unclear evolution, also considered as malignant in the analysis of the imaging results. In total, 16/19 cancer cases had increased stiffness on elastography. The cancer prevalence increased with TI-RADS category, being 25% in TI-RADS 4b category and 92.8% in TI-RADS 5 category. The AUROC (Area Under Receiver Operating Curve) of elastography alone, in differentiation of malignant thyroid nodules was 74.9%; the combination of elastographic and conventional ultrasound characteristics generated an even better AUROC, of 84.5%. The combined conventional ultrasound and elastography identified thyroid cancer in cases with intermediate cytology with a sensitivity of 89.5% with a specificity of 50%. High risk thyroid nodules, identified by combined high risk conventional ultrasound characteristics and increased stiffness, on strain elastography, are highly predictive for malignancy, in the intermediate cytology cases.

Extreme Learning Machine for Thyroid Nodule Classification with Graph Cluster Ant Colony Optimization Based Feature Selection

Thyroid nodule is defined as an endocrine malignancy that occurs in humans due to abnormal growth of cells. Recently, an increasing level of thyroid incidence has been identified worldwide. Thus, it is necessary to detect the nodules at an early stage. Ultrasonography is an important tool that is utilized for the detection as well as differentiation of malignant thyroid nodules from benign nodules. The nodules in ultrasound appear in different heterogenic forms, which are difficult to differentiate by the physicians. Further, large number of features available in US characteristics increases the computation time as well as complexity of classification. In this paper, Graph-Clustering Ant Colony Optimization based Extreme Learning Machine approach is proposed to achieve efficient diagnosis of thyroid nodules. It will enhance thyroid nodule classification by selecting only the optimal features and further using it for improving the function of classifier. The main goal of this technique is to differentiate the malignant nodules from the benign nodules. The performance of both feature selection and classification are evaluated through parameters such as accuracy, AUC, sensitivity and specificity. From the experimental results, it is revealed that the proposed method is significantly better than the existing methods. Thus, it is considered to be an effective tool for diagnosing the thyroid nodules with less complexity and reduced computation time.

Diagnostic performance of HMGA2 gene expression for differentiation of malignant thyroid nodules: A systematic review and meta-analysis.

The purpose of the current study was to investigate the diagnostic performance of high mobility group A2 (HMGA2) gene expression for differentiation of malignant thyroid nodules through a systematic review and meta-analysis. The MEDLINE/PubMed and EMBASE database, from the earliest available date of indexing through 10 April 2018, were searched for studies evaluating the diagnostic performance of HMGA2 expression for differentiation of thyroid nodules. We determined the sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR-), and constructed summary receiver operating characteristic (ROC) curves. Across 7 studies, the pooled sensitivity for HMGA2 expression was 0.78 (95% CI; 0.67-0.86) with heterogeneity (I2 =86.6) and a pooled specificity of 0.94 (95% CI: 0.85-0.98) with heterogeneity (I2 =94.7). Likelihood ratio (LR) syntheses gave an overall positive likelihood ratio (LR+) of 12.6 (95% CI: 5.1-31.3) and negative likelihood ratio (LR-) of 0.24 (95% CI: 0.15-0.36). The pooled diagnostic odds ratio (DOR) was 53 (95% CI: 18-159). Hierarchical summary ROC curve indicates that the areas under the curve were 0.92 (95% CI: 0.89-0.94). In meta-regression analysis, no definite variable was the source of the study heterogeneity. The current meta-analysis showed the moderate sensitivity and high specificity of HMGA2 expression for differentiation of malignant thyroid nodules. The likelihood ratio scatter-gram suggested that HMGA2 expression analysis could be useful for confirmation of the presence of malignant thyroid nodules. Considering the heterogeneity of included studies, further large prospective studies are necessary to confirm these results.

Diagnostic Performance of Technetium-99m Methoxy-Isobutyl-Isonitrile for Differentiation of Malignant Thyroid Nodules: A Systematic Review and Meta-Analysis.

The purpose of the current study was to investigate the diagnostic performance of technetium-99m (Tc-99m) methoxy-isobutyl-isonitrile (MIBI) for differentiation of malignant thyroid nodules (TN) through a systematic review and meta-analysis. The MEDLINE/PubMed and EMBASE database, from the earliest available date of indexing through January 31, 2018, were searched for studies evaluating the diagnostic performance of Tc-99m MIBI for TN. The sensitivities and specificities were determined across studies, positive and negative likelihood ratios (LR+ and LR-) were calculated, and summary receiver operating characteristic curves were constructed. Across 22 studies (2421 patients), the pooled sensitivity for Tc-99m MIBI thyroid scan was 0.87 [confidence interval (CI) 0.76-0.93] with heterogeneity (I2 = 92.3) and a pooled specificity of 0.78 [CI 0.67-0.86] with heterogeneity (I2 = 96.4). LR syntheses gave an overall LR+ of 4.0 [CI 2.5-6.3] and LR- of 0.17 [CI 0.09-0.32]. The pooled diagnostic odds ratio was 24 [CI 63-176]. The hierarchical summary receiver operating characteristic curve indicates that the area under the curve was 0.90 [CI 0.87-0.92]. In meta-regression analysis, no definite variable was the source of the study heterogeneity. The current meta-analysis shows a moderate sensitivity and specificity of Tc-99m MIBI thyroid scan for differentiation of malignant TN. However, the diagnostic odds ratio was relatively low and the LR scattergram indicated that Tc-99m MIBI thyroid scan is not useful for confirming the presence of malignant TN or for its exclusion. Therefore, Tc-99m MIBI thyroid scans should be used restrictively and interpreted cautiously when assessing TN for malignancy.

Acoustic Radiation Force Impulse (ARFI) imaging for the distinction between benign and malignant thyroid nodules.

The aim of the present study was to evaluate thyroid nodules using virtual touch quantification (VTQ) of force impulse acoustic radiation (ARFI) imaging and to investigate a cutoff value for the differentiation of malignant thyroid nodules. Ninety-five patients with quantitatively-assessed (VTQ) thyroid nodules were evaluated with ARFI imaging in this prospective study. ARFI imaging with VTQ was performed only on the nodules which were expected to undergo fine-needle aspiration biopsy (FNAB). All of the thyroid lesions were examined histopathologically. The mean shear wave velocity (SWV) value of the malignant nodules (3.18±0.39m/s) was higher than that of the benign nodules (2.11±0.53m/s). There was a statistically significant difference between the mean SWV values of benign and malignant nodules (p<0.001). A SWV cutoff value of greater than 2.66m/s yielded sensitivity and specificity values of 100 and 82.3%, respectively, for diagnosis of malignant nodules. VTQ of ARFI imaging has high sensitivity and specificity for discriminating between benign and malignant thyroid nodules and may positively contribute to clinical evaluation of these nodules.

The efficacy of apparent diffusion coefficient value calculation in differentiation between malignant and benign thyroid nodules

PurposeTo evaluate the efficacy of apparent diffusion coefficient (ADC) calculation in differentiation between malignant and benign thyroid nodules. Methods and materialsA prospective study was conducted in 52 patients. Diffusion-weighted echoplanar imaging was performed and b factors were taken as 0 and 400 s/mm2. ResultsThe mean ADC value for malignant thyroid nodules was 0.829±0.179×10−3 mm2/s and that for benign thyroid nodules was 1.984±0.482×10−3 mm2/s. The mean ADC value for malignant nodules was significantly lower than that for benign nodules (P=.0001). ConclusionADC value calculation is an effective method in differentiation of malignant thyroid nodules from benign ones.

Evaluation of thyroid nodules with technetium-99m MIBI and technetium-99m pertechnetate.

Most thyroid centers use fine-needle aspiration (FNA) and technetium-99m pertechnetate for the preoperative assessment of thyroid nodules. This approach is sufficient in most cases other than follicular neoplasm, and follicular carcinoma is more common than papillary carcinoma in developing countries such as in our center. Technetium 99m-methoxyisobutylisonitrile (MIBI) proposed for myocardial perfusion was also found to be taken up by a variety of tumors including thyroid cancer. We evaluated MIBI uptake of nodular thyroid disease and compared it with pertechnetate scan, FNA, and histologic findings for the differentiation of malignant thyroid nodules from benign lesions. Seventy-one patients were included in the study. Three-phase pertechnetate scintigraphy was completed after a single injection of 150 MBq. Perfusion/uptake mismatch (uniform perfusion with cold uptake) was regarded as positive for malignancy, whereas perfusion/uptake match (cold perfusion with cold uptake) was regarded as negative. After 1 week, 400 MBq of MIBI was injected, images were obtained at 20 minutes and 2 hours, and evaluated semiquantitatively by use of a 4-point (0-3) scoring system. MIBI scans were considered positive if there was uptake superior to normal thyroid tissue on early and delayed images (score = 3). In the following days and weeks, all patients underwent FNA followed by surgery. Histopathologic diagnosis revealed a total of 23 thyroid carcinomas, 21 (91%) and 19 (83%) were positive on MIBI and pertechnetate, respectively. Of the 48 patients with benign nodules, 11 (23%) and 29 (60%) were positive on MIBI and pertechnetate, respectively. The specificity of MIBI, pertechnetate, and FNA is 77%, 40%, and 90%, respectively. In combination with FNA and three-phase pertechnetate scan, MIBI could be helpful in preoperative assessment of thyroid nodules. Intense MIBI activity increases the probability of thyroid cancer, whereas reduced activity drastically decreases the probability of malignancy.