Evaluation of Extrathyroidal Extension of Papillary Thyroid Microcarcinoma With Three-Dimensional Tomographic Ultrasound Imaging / 中国医学科学院学报

Objective To evaluate extrathyroidal extension (ETE) in papillary thyroid microcarcinoma (PTMC) with three-dimensional tomographic ultrasound imaging (3D-TUI). Methods A total of 97 thyroid nodules of 79 patients with PTMC treated in PUMC Hospital from February 2016 to January 2018 were included in this study.Two ultrasound experts performed independent blinded assessment of the relationship between thyroid nodules and thyroid capsule by two-dimensional ultrasound (2D-US) and 3D-TUI.The results of 2D-US and 3D-TUI in evaluating ETE were compared with intraoperative findings and postoperative histological and pathological results. Results Among the 97 nodules,54 (55.7%) nodules had ETE.The diagnostic sensitivity (68.5% vs.37.0%;χ2=10.737,P=0.002),accuracy (74.5% vs.56.7%;χ2=6.686,P=0.015),and area under the receiver operating characteristic curve[0.761 (95%CI=0.677-0.845) vs.0.592 (95%CI=0.504-0.680);Z=3.500,P<0.001] of 3D-TUI were higher than those of 2D-US.However,3D-TUI and 2D-US showed no significant difference in the specificity (84.1% vs.81.4%;χ2=0.081,P=0.776),negative predictive value (67.9% vs.50.7%;χ2=3.645,P=0.066),or positive predictive value (84.1% vs.71.4%;χ2=1.663,P=0.240). Conclusion Compared with 2D-US,3D-TUI demonstrates increased diagnostic efficiency for ETE of PTMC.

Association of Body Mass Index and Risk Stratification of Thyroid Nodules in a Multi-center Healthy Population / 中国医学科学院学报

Objective To investigate the relationship between body mass index(BMI)and risk levels of thyroid nodules in a multi-center healthy population. Methods A total of 6070 subjects were enrolled from five medical physical examination centers in China from January 2015 to December 2017. All the participants'general information and parameters were recorded. Thyroid nodules were detected by color Doppler ultrasonography. All ultrasound doctors received uniform training before study. Results Among all the subjects,5773(95.1%;with 4274 nodules identified in 2833 subjects)were from northern China and 297(4.9%,with 183 nodules identified in 158 subjects)from central China(χ=1.923,P=0.092). The nodules were single in 1479 of 2991 subjects(49.4%)and multiple in 1512 subjects(50.6%). Nodules larger than 1 cm accounted for 13.3% and nodules smaller than 1 cm accounted for 86.7%. Compared with the non-thyroid nodule group,the thyroid nodule group had significantly more women(χ=156.36,P=0.000),older age(t=-18.768,P=0.000),and higher fasting blood glucose(FBG) level(t=-3.808,P=0.000). Among all the nodules,the prevalence rates of benign,very-low-risk,low-risk,moderate risk,and high risk were 4.5%,6.6%,85.0%,0.1%,and 3.7%,respectively,according to the ATA guidelines. Notably,there were 4291 nodules at moderate or lower risks and 166 nodules at high risk. Compared with the former,patients with high-risk nodules had significantly lower BMI(χ=25.161,P=0.000)and high FBG(t=3.357,P=0.000). Multivariate non-conditional Logistic regression showed low BMI(OR=2.900,95%CI:1.461-5.783,P=0.002)and high FBG level(OR=0.803,95%CI:0.675-0.955,P=0.013)were independent risk factors for high-risk nodules. Compared with subjects with normal weight or obese populations,subjects with low BMI had significantly higher detection rate of high-risk nodules(χ=25.16,P=0.000). In ≥55 year-old group,significantly more high-risk nodules were detected in low BMI group(χ=44.868,P=0.000). Conclusion Low weight is associated with high-risk thyroid nodules among people ≥55 years old.

Diagnostic Value of Elastography for Thyroid Nodules in Hashimoto's Thyroiditis / 中国医学科学院学报

Objective To evaluate the diagnostic performance of elastography in the diagnosis of thyroid nodules in the context of Hashimoto's thyroiditis(HT). Methods The study evaluated 43 thyroid nodules by conventional ultrasound (CU) and elastography in 38 patients co-existed with HT who were referred for operation. The patients underwent CU and elastography before operation. The sensitivity,specificity,positive and negative predictive values,and accuracy for CU,elastography,and combination of these two techniques were assessed by using histopathological results as the gold standard. Results Among these 43 thyroid nodules,pathology confirmed 29 (67.4%) malignant nodules and 14 (32.6%) benign ones. There were statistically significant differences between malignant and benign groups in features such as solid shape (96.6% vs. 64.0%;OR:15.6,95%CI:1.600-151.262,P=0.004),irregularity (90.0% vs. 42.9%;OR:11.6,95%CI:2.341-57.032,P=0.001),taller than wide shape (72.0% vs. 21.4%;OR:9.6,95% CI:2.117-43.753,P=0.002),microcalcification (69% vs. 28.6%;OR:5.6,95% CI:1.368-22.556,P=0.012) and irregular blood flow (90.0% vs. 28.6%;OR:17.3,95%CI:3.186-94.290,P=0.000). The diagnostic performance of elastography and CU was as follows:sensitivity (86.2 % vs.96.6%),specificity (71.4% vs.42.9%),positive predictive value (86.2% vs.77.8%),negative predictive value (71.4% vs.85.7%),and accuracy (81.4% vs.79.0%). The combination of these two techniques had a sensitivity of 93.1%,a specificity of 71.4%,a positive predictive value of 87.1%,a negative predictive value of 83.3%,and an accuracy of 86.0%. Conclusions Elastography has a higher specificity in the diagnosis of thyroid nodules in HT,while its sensitivity is slightly lower than that of CU. Combination of these two techniques can increase the specificity and accuracy.

Comparison of Ultrasound Features of Primary Metastatic Papillary Thyroid Carcinoma and Recurrent/Persistent Metastatic Cervical Lymph Nodes / 中国医学科学院学报

Objective To explore the ultrasound features and levels of cervical lymph node metastases in primary and recurrent/persistent papillary thyroid cancer (PTC).Methods We retrospectively analyzed the clinical data of 2181 patients who underwent cervical lymph nodes dissection for PTC from January 12015 to January 12016.Totally 418 PTC patients (with 622 lymph nodes) who met the inclusion criteria entered the final analysis.Patients who had not received any prior thyroid treatment (surgery with or without radioactive iodine) were categorized as the primary group (352 patients with 527 metastatic lymph nodes),and patients who had received prior treatment (thyroidectomy with or without radioactive iodine) for PTC were categorized as recurrent/persistent group (66 patients with 95 metastatic lymph nodes).Pathological results from lymph node dissections were used as the gold standards by means of level-to-level analysis.Results The mean of the minimum axis diameter of the lymph nodes in the primary group was (6.7±3.6)mm,and that of the recurrent/persistent group was (6.6±3.1)mm (U=0.180,P=0.857).The proportion of metastasis in the central area of primary group was 40.0%,which was significantly higher than that in the recurrent/persistent group (12.6%);the proportion of metastasis in the lateral area was 60.6% in the primary group,which was significantly lower than that in the recurrent/persistent group (87.4%)(χ=26.288,P<0.001).In lateral metastatic lymph nodes,Ⅲ level was the most common place in both groups.Level Ⅴ metastatic lymph was rare in both primary group and recurrent/persistent group.Calcifications (63.1% vs. 48.2%;χ=7.207,P=0.007) and peripheral vascularity (81.1% vs. 59.4%;χ= 16.147, P<0.001) were more common in the recurrent/persistent group.The round shape,absence of an echogenic hilum,hyperechogenicity,and cystic aspects were not significantly different between these two groups (all P>0.05).Conclusions Primary metastatic lymph nodes often occur in the central area of lymph nodes,while lateral metastatic lymph nodes are more common in recurrent/persistent PTC.For metastatic lymph nodes,calcifications and peripheral vascularity are more common in recurrent/persistent PTC.

Diagnostic value of contrast-enhanced ultrasound of thyroid nodules coexisting with Hashimoto's thyroiditis / 中国医学科学院学报

<p><b>OBJECTIVE</b>To evaluate the value of contrast-enhanced ultrasound (CEUS) in diagnosing thyroid nodules coexisting with Hashimoto's thyroiditis (HT).</p><p><b>METHODS</b>Totally 62 thyroid nodules in 48 HT patients were retrospectively analyzed. The CEUS characteristics were reviewed, and diagnostic value of enhancement pattern and peak intensity were calculated.</p><p><b>RESULTS</b>Peak intensity (P=0.002) and enhancement pattern (P<0.001) differed significantly between malignant and benign thyroid nodules. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of heterogeneous enhancement were 97.6%, 85.7%, 93.0%, 94.7%, and 93.5%, respectively. Sensitivity, specificity, PPV, NPV and accuracy of low intensity at peak time were 85.4%, 52.4%, 77.8%, 64.7%, and 74.2%, respectively.</p><p><b>CONCLUSIONS</b>Heterogeneous enhancement is effective in the diagnosis of malignant thyroid nodules coexisting with HT. CEUS can improve the diagnostic accuracy in distinguishing thyroid nodules with unknown malignancy under the conventional ultrasound.</p>

Discrepancy of Papillary Thyroid Carcinoma Sizes Measured by Ultrasonography and Pathology / 中国医学科学院学报

<p><b>OBJECTIVE</b>To compare the size of papillary thyroid carcinoma on ultrasonography(US)and the actual size measured during histological examination and to discuss the potential causes of such discrepancy.</p><p><b>METHODS</b>A total of 148 patients with histologically confirmed papillary thyroid carcinoma underwent thyroid surgery in our center from December 2012 to May 2013. Patients were stratified based on the size,morphology,margin,cystic component,and presence of Hashimoto's disease to compare the discrepancy of the US and pathalogical measurements.</p><p><b>RESULTS</b>The mean sizes of the nodules measured by US and pathology were(1.58±0.94)cm and(1.33±0.84)cm,respectively(P=0.000). In 70.9%(105/148)of the nodules,the sizes measured by US were larger than those measured by pathology. In 17.6%(26/148)of the nodules,the sizes measured by US were smaller than those measured by pathology. In 1.1-1.4 cm size subgroup,the difference between mean ultrasound diameter and pathologic diameter was not significant [(1.21±0.11)cm vs.(1.11±0.32)cm,P=0.062]. In 0.1-1.0 cm size subgroup,the mean sizes of the nodules measured by US and pathology were(0.75±0.19)cm and(0.62±0.23)cm,respectively(P=0.000). In ≥1.5 cm size subgroup,the mean sizes of the nodules measured by US and pathology were(2.48±0.70)cm and(2.03±0.81)cm(P=0.000).</p><p><b>CONCLUSIONS</b>There is a significant discrepancy between US and pathologic size measurements for papillary thyroid carcinoma. However,for nodules sized 1.1-1.4 cm,the ultrasound and pathologic measurements are more likely to be consistent.</p>

Ultrasonographic features of thyroid nodules accompanied by Hashimoto thyroiditis / 中国医学科学院学报

<p><b>OBJECTIVE</b>To compare the ultrasound imaging characteristics of benign and malignant thyroid nodules on the background of Hashimoto's thyroiditis (HT).</p><p><b>METHODS</b>Totally 120 consecutive patients with pathologically confirmed benign (n=60) or malignant (n=60) thyroid nodules in Peking Union Medical College Hospital since January 2013 were retrospectively analyzed, and their preoperative ultrasound images were reviewed.</p><p><b>RESULTS</b>Sixty cases (100%) of the malignant nodules were papillary thyroid cancers. In the benign group, 33 cases (55.0%) had nodular changes of HT, 26 (43.3%) had nodular goiter, and one (16.7%) had adenoma. Compared with the benign ones,the malignant nodules were more likely to be solid (91.7% vs. 68.3%, P=0.001), hypoechoic (96.7% vs. 48.3%, P=0.000), ill defined (95.0% vs. 41.7%, P=0.000), irregular (96.7% vs. 43.4%, P=0.000), and more easily to have such characteristics as micro-calcification (71.7% vs. 30.0%, P=0.000), absence of regular halo (96.7% vs. 65.0%, P=0.000), taller-than-wide sign (46.7% vs. 13.3%, P=0.000), and locally increased or irregular blood flow (61.7% vs. 26.7%, P=0.000).</p><p><b>CONCLUSIONS</b>Ultrasound has an ideal overall sensitivity in differentiating nodules on the background of HT. Solid structure, hypo-echogenicity, ill-defined margin, irregular shape, and absence of regular halo are good screening ultrasound markers. Except for the A/T≥1, the other variables have less satisfactory diagnostic specificity.</p>

Diagnostic values of ultrasound and (18)F-fluoro-2-deoxy-D-glucose-positron emission tomography/computerized tomography for patients with suspected thyroid carcinoma and lymph node metastasis / 中国医学科学院学报

<p><b>OBJECTIVE</b>To evaluate the diagnostic values of ultrasound (US) and (18)F-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG PET)/computerized tomography (CT) in diagnosing suspected thyroid carcinoma and lymph node metastasis.</p><p><b>METHODS</b>The clinical data of 28 patients who had undergone total or subtotal thyroidectomy with or without neck dissection from December 2011 to December 2012 in PUMC Hospital and had undergone US and FDG PET/CT before surgery were retrospectively analyzed. In each patient, US and FDG PET/CT images were retrospectively reviewed to determine the presence of carcinoma with or without loco-regional metastasis by level-by-level analysis. The potential correlation between imaging results and histopathology were analyzed.</p><p><b>RESULTS</b>There were 11 benign lesions,15 papillary carcinomas, one follicular carcinoma, and one medullary carcinoma. For thyroid carcinoma,the sensitivity and specificity were 88.2% and 63.6% for US and 76.5% and 54.5% for FDG PET/CT(P>0.05). For lymph node metastasis, the sensitivity was 68.0% for US and 60.0% for FDG PET/CT (P>0.05), and the specificity was 96.7% for US and FDG PET/CT.FDG PET/CT could provide more diagnostic information than US for patients with level 2 or 5 metastasis.</p><p><b>CONCLUSIONS</b>Combination of US and FDG PET/CT is typically not needed for differentiating thyroid lesions.However, for patients with suspected lymph node metastasis of infrequently involved levels, the combination of US and FDG PET/CT may be a good choice.</p>

Usefulness of ultrasonography in the differential diagnosis of thyroidal follicular tumor / 中国医学科学院学报

<p><b>OBJECTIVE</b>To evaluate the usefulness of ultrasonography in distinguishing follicular carcinoma from adenoma.</p><p><b>METHODS</b>The ultrasound data of 37 patients with histopathologically confirmed follicular carcinomas who were treated in PUMC Hospital from January 2000 to November 2012 were retrospectively studied. In addition, 74 sex-and age-matched patients with histopathologically confirmed adenomas during the same period were enrolled as the control group. The pathologic results were regarded as the gold standard.</p><p><b>RESULTS</b>Irregular shape (32.4% of follicular carcinoma vs 5.4% of adenoma), absence of thin halo (67.6% vs 36.5%), indistinct margin (21.6% vs 1.4%), hypoechoic appearance (64.9% vs 39.2%), punctuate calcification(40.5% vs 13.5%), absence of cystic change (78.4% vs 54.1%), and being complicated with other thyroid disease (56.8% vs 28.4%) were more frequently associated with follicular carcinoma than with benign adenoma (P<0.05). No significant difference in the echotexture and internal flow was observed between the two groups (P>0.05).</p><p><b>CONCLUSION</b>Although follicular carcinoma and adenoma share many sonographic features, irregular shape, absence of thin halo, indistinct margin, hypoechoic appearance, punctuate calcification, absence of cystic change, and being complicated with other thyroid disease favor a follicular carcinoma diagnosis.</p>