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

Clinical and Ultrasonographic Features of Papillary Thyroid Carcinoma Located in the Isthmus

ABSTRACT

The aim of this research was to investigate the clinical and ultrasonographic features of papillary thyroid carcinoma (PTC) in the isthmus. A total of 823 patients with 823 PTCs including 133 in the isthmus and 690 in the lateral lobe were included in our study. All patients were confirmed by postoperative pathology. The clinical and ultrasonographic characteristics were retrospectively analyzed and compared. Univariate analysis and multivariate logistic regression analysis were performed. Multifactor analyses showed that PTC in the isthmus was significantly different from PTC originating from the lateral lobe in aspect ratio, microcalcification, extrathyroid extension, lymph node metastases, and lymph node density ( P < 0.05, for all). There were no significant differences in age, sex, tumor size, margin, halo, echogenicity, and homogeneity ( P > 0.05, for all). The results indicated that the sonographic appearances of PTC in the isthmus were relatively atypical; however, it had a higher incidence of extrathyroidal extension, central lymph node metastasis, and a tendency of higher lymph node density. Therefore, more careful ultrasound evaluation should be performed for these nodules.

Ultrasound features and preoperative accuracy of the fine needle aspiration biopsy in detection of thyroid carcinomas

OBJECTIVE

To analyze the ultrasound (US) characteristics and fine needle biopsy (FNAB) of thyroid carcinomas (TCs) prior to surgery and compare with postoperative histopathology and to determine FNAB sensitivity and specificity.

MATERIAL AND METHODS

Retrospective analysis of the US data during 1999-2015 was performed, as well as analysis of FNAB results and using histopathology report as "gold standard" the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of this method was evaluated.

RESULTS

Data revealed that tumors >51 mm were declining by 50% in the period 2011-2015 compared to 2005-2010 or by 18% 2011-2015 compared to 1999-2004 and significant increase was detected in diagnosis of multicentric tumors. The analysis revealed that FNAB has sensitivity = 65.7% CI (0.59% - 0.71%) and specificity = 50% CI (0.43%-0.56%), PPV = 56.9% and NPV = 59.2%.

CONCLUSION

We found increasing detection of smaller TCs, as well as more frequent detection of multicentricity of the neoplastic foci. FNAB results in our study revealed low sensitivity and specificity. Major limitation of the study was inability to exactly separate US guided from non US guided FNAB in evaluation of the sensitivity and specificity, due to retrospective nature of the analysis. Further studies evaluating only US guided FNAB should be performed.

Transverse and Longitudinal Ultrasound Location of Thyroid Nodules and Risk of Thyroid Cancer

BACKGROUND

The high prevalence of thyroid nodules demands accurate assessment tools to avoid unnecessary biopsies. Prior studies demonstrated a correlation between the longitudinal location of thyroid nodules and the likelihood of malignancy. No study has evaluated the predictive value of transverse location on ultrasonography with malignancy.

METHODS

We retrospectively reviewed the records of thyroid nodules that underwent fine-needle aspiration over 13 years, including demographics, risk factors, nodule sonographic features, location, and surgical pathology. Univariate and multivariable logistic regression models were used to evaluate the risk of malignancy.

RESULTS

Of the 668 thyroid nodules, 604 were analyzed with a definitive diagnosis. Thirty-seven nodules were malignant, representing a prevalence of 6.1%. In the longitudinal plane, the upper pole nodules carried the highest incidence of malignancy (14.9%). In the transverse plane, the highest incidence of malignancy occurred in nodules located laterally (12.5%) and anterior-laterally (11.8%). Compared with the upper pole, the odds of malignancy were significantly lower for lower pole (odds ratio [OR] = 0.26, 95% confidence interval [CI]: 0.09-0.70) and midlobe nodules (OR = 0.31, 95% CI: 0.12-0.83). In the transverse plane, posteriorly situated nodules carried a significantly lower risk of malignancy (OR = 0.07, 95% CI: 0.01-0.69). Multiple logistic regression confirmed these associations after adjusting for age, sex, family history, radiation exposure, nodule size, and sonographic characteristics.

CONCLUSION

Both the transverse and longitudinal planes were independent predictors of cancer in thyroid nodules. Lateral, anterior-lateral, and upper pole nodules carried the highest risk and posterior nodules had the lowest risk of malignancy.

Impact of ultrasound-guided fine needle aspiration cytology for diagnosis of thyroid nodules

BACKGROUND

Previous clinical studies have reported that ultrasound-guided fine needle aspiration cytology (UGFNAC) can be used for the diagnosis of thyroid nodules (TN) effectively. However, no study has systematically explored its diagnosis accuracy in patients with TN. Thus, this study will assess its diagnosis accuracy for TN.

METHODS

We will perform a comprehensive literature search from the following databases from their inceptions to the present without language restrictions: MEDILINE, EMBASE, Cochrane Library, Web of Science, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. We will consider all case-controlled studies investigating the impacts of UGFNAC diagnosis for patients with TN for inclusion. Two authors will independently carry out study selection, data collection, and methodological quality assessment. Quality Assessment of Diagnostic Accuracy Studies tool will be used for methodological quality evaluation. We will use RevMan V.5.3 and Stata V.12.0 software to perform statistical analysis.

RESULTS

We will apply sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio to judge the diagnostic accuracy of UGFNAC for TN.

CONCLUSION

The results of this study will provide latest evidence for the diagnostic accuracy of UGFNAC for TN.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019138805.

Value of differential diagnosis of contrast-enhanced ultrasound in benign and malignant thyroid nodules with microcalcification

Value of differential diagnosis of contrast-enhanced ultrasound in benign and malignant thyroid nodules with microcalcification was explored. A total of 184 patients with thyroid nodules with microcalcification, treated in People's Hospital of Shanxi Province from April 2015 to March 2017, were selected as research subjects. Contrast-enhanced ultrasound was used for imaging examination of the thyroid nodules. Three regions of interest were drawn at the positions with the strongest ultrasound imaging, for which the time-intensity curve (TIC), time to peak (Tp), peak intensity (Peak), area under curve (AUC) and mean transit time (MTT) were obtained separately. The features of contrast-enhanced ultrasound for malignant thyroid nodules were manifested as irregular focus edge, unclear boundary, low fiber reinforcement of the whole focus, uneven distribution of images and blood perfusion defect inside the focus, especially severe blood perfusion defect in the nodule center. The TIC showed a slow ascending and slow descending trend in general. The TIC features and the features of contrast-enhanced ultrasound for malignant thyroid nodules were prominently different from those for benign thyroid nodules. Compared with those in the surrounding normal tissues of thyroid gland, the Peak was remarkably shorter, and the AUC was notably smaller in the center and edge of malignant thyroid nodules (P<0.05); and the nodule center had obviously shorter Peak and smaller AUC than the nodule edge (P<0.05). Furthermore, in comparison with those of malignant thyroid nodules, the Peak was extended and AUC was enlarged markedly in the center and edge of benign thyroid nodules (P<0.05). In conclusion, the contrast-enhanced ultrasound can preferably compare the lesions of benign and malignant thyroid nodules with microcalcification, which possesses certain value in the differential diagnosis of benign and malignant thyroid nodules.

THYROID NODULE LOCATION ON ULTRASONOGRAPHY AS A PREDICTOR OF MALIGNANCY

OBJECTIVE

The diagnostic capacity of ultrasonography (US) for differentiating between malignant and benign thyroid nodules is crucial in preventing unnecessary invasive procedures. This is the first study to evaluate whether thyroid nodule location on US has predictive value for malignancy.

METHODS

We retrospectively reviewed data from 219 patients with thyroid nodules who underwent fine-needle aspiration biopsy in 1 year. Patients' demographics as well as nodule's laterality, polarity, morphology, and multinodularity were analyzed. All malignant lesions were confirmed by surgical pathology.

RESULTS

The majority of the patients were female (86.2%). Nodules were evenly distributed between the right lobe (46.3%) and left lobe (49.5%). Eight nodules (4.2%) were located in the isthmus. Most nodules (79.3%) were located in the lower pole, while 9.6% were located in the upper pole and 6.9% in the middle pole. Seventy-five patients (39.9%) had multiple nodules. Fourteen nodules were malignant, representing a prevalence of 7.4%. A significantly higher frequency of malignancy was observed in upper pole (22.2%) compared to lower pole (4.7%) and middle pole (15.4%). A multiple logistic regression model confirmed such association after adjusting for age, body mass index, multinodularity, and laterality. The odds of malignancy in the upper pole were 4 times higher than other locations (odds ratio, 4.6; P = .03).

CONCLUSION

Our study is the first showing that thyroid nodules located in the upper pole can be considered as having higher risk for malignancy. It may enhance the predictive value of malignancy if it is included in thyroid nodule ultrasound classification guidelines.

ABBREVIATIONS

AACE = American Association of Clinical Endocrinologists; ATA = American Thyroid Association; BMI = body mass index; FNA = fine-needle aspiration; TMS = total malignancy score; TTW = taller than wide; US = ultrasonography.