Neck Ultrasonography Diagnosis Lymph Node Metastasis In Patients With Differentiated Thyroid Carcinoma

Part ?Neck Ultrasonography Diagnosis of Different levels Cervical Lymph Node Metastasis in Patients with Differentiated Thyroid CarcinomaObjective:To explore the diagnostic value of neck ultrasonography in detecting different levels of cervical lymph node metastasis in patients with Differentiated thyroid carcinoma and evaluate the optional value of the shortest axis of ultrasound in diagnosis of metastatic lymph node.Methods:A total of 650 cervical lymph nodes(central 262,lateral 388)were examined in 441(310 females and 131 males)consecutive PTC patients.We assessed the US diagnosis of metastatic LNs using a level-by-level analysis.After surgery,all LNs were classified asnodes with metastasis and nodes without metastasisaccording tothe pathological results.The minimal axial diameter,longitudinal/transverse axis ratio and presence or absence of hyperechoic hilum,microcalcifications,hyperechogenicity,cystic features and peripheral vascularity of LNs were assessed by US.We worked out the sensitivity,specificity of each sign of US image in predicting lymph node metastasis.Using Receiver operating characteristic(ROC)curve,we obtained the cutoff value of the minimal axial diameter for different levels of cervical metastatic LN.Results:A significant difference was observed in theminimal axial diameter between the metastatic(6.74±3.64mm;95%Cl:6.43 mm,7.06 mm)and benign(5.10±1.97mm;95%Cl:4.78 mm,5.46 mm)LNs(P<0.001).The mean minimal axial diameter of lateral metastatic LNswas greater than that of central metastatic LNs(7.24±4.05mm vs 5.99±2.76mm).According to the ROC curve analysis,the cutoff value of the minimal axial diameter of metastatic LNs was 5.5mm for all level of cervical lymph nodes.By this cutoff value,sensitivity and specificity for central LNs was 46.5%and 71.4%respectively,and for lateral LNs was 59.8%and 67.1%.When cutoff valuesof 8.0mm and 10.0mm were used for the central and lateral levels,respectively,to detect LN metastasis,which are the valuesrecommended by the ATA guidelines,the sensitivity were23.9%and 18.4%,the specificity were 87.7%and 100%,respectively.Microcalcifications,and peripheral vascularization with a high sensitivty(48.1%,59.0%)and specificity(78.4%,62.9%).The specificity of hyperechogenicity andcystic features was higher,yet their sensitivity was relatively low.Microcalcifications,hyperechogenicity,cystic features and peripheral vascularization were more common in the lateral metastatic LNs(P<0.001),and a round shape was more common in central malignant LNs(P<0.001).Conclusion:The cutoff value of minimum axis diameter of ultrasound in predicting the metastatic lymph nodes was 5.5mm,which could predict more lateral lymph nodes than central ones.Peripheral vascularization is an important sign of central and lateral metastatic lymph nodes.Microcalcifications,hyperechogenicity,cystic features and peripheral vascularization were more common in the lateral metastatic LNs,and a round shape was more common in central malignant LNs.Part ?Diagnostic Performance of Neck Ultrasonography and Basal Serum Thyroglobulin in Predicting the Recurrence or Persistence of Differentiated Thyroid CarcinomaObjective:Our objective is to investigate the diagnostic value of b-Tg and neck ultrasonography in predicting the recurrence or persistence of DTC.Methods:We retrospectively analyzed 123 DTC patients after total or near total thyroidectomy during their follow-up between December 2008 and September 2015 at our hospital.All patients received routine post-surgery b-Tg tests and neck ultrasonography.Of the 123 patients,60 had a recurrence or persistence disease and had thus undergone a second surgery for pathological verification;63 remained disease-free as verified by imaging or pathology.Results:For predicting the recurrence or persistence of DTC,the most accurate basal Tg value was greater than 0.26 ng/ml(sensitivity 73.3%,specificity 77.8%,positive predictive value 75.9%and negative predicative value 75.4%);neck ultrasonography alone had a diagnostic sensitivity of 85.0%,specificity of 90.5%,positive predictive value of 89.5%and negative predicative value of 86.3%;The combination of basal Tg and neck ultrasonography had a sensitivity of 93.3%,specificity of 69.8%,positive predictive value of 74.7%and negative predicative value of 91.7%.Conclusion:Our data indicates that the performance of basal Tg levels and neck ultrasonography alone are dependable in predicting the recurrence or persistence of DTC,and the negative predictive value are improved by combining these two procedures,which means that there was a significant increase in the likelihood of excluding recurrent or metastatic DTC.