Study On The Value Of Preoperative Ultrasonography Combined With Serum TSH Level In The Diagnosis Of Thyroid Nodules

Purpose: The purpose of this study was to combine the preoperative ultrasonography(US) image features and serum thyroid stimulating hormone(TSH) level to evaluate benign and malignant thyroid nodules,which can improve the preoperative diagnostic accuracy of thyroid nodules.Methods: A retrospective analysis of the clinical data of 478 patients with thyroid nodules. Collecting the clinical data that included the age,sex and family history of malignancy. US image features of thyroid nodules was analyzed, including border,shape, extracapsular invasion,nodule size, aspect ratio, calcification, parenchyma and internal echo, rear acoustic attenuation, cervical lymphadenectasis and the blood supply of nodules. Collected the preoperative serum TSH level. Divided into benign group(N=388) and malignant nodules group(N=90) based on the postoperative pathological results. The enumeration data of all the paringfactors in the two groups were analyzed by ?2 test and the measurement data were analyzed by t test, P<0.05, the difference was statistically significant. Then divided the preoperative serum TSH level from low to high into five groups that estimate the relationship between the level of preoperative serum TSH and the thyroid nodules. Taking(1-specificity)as the abscissa and the sensitivity as the vertical axis to draw the receiver operating characteristic curve(ROC) which can calculate a cut-off point to get odds ratio. Calculated the sensitivity and specificity of US imaging feature combined with preoperative serum TSH level, then draw ROC curve to evaluate the thyroid nodule diagnosis rate.Results: There had significant differences of the age, family history of benign group and malignant group(P<0.05), but the difference was not statistically significant of gender( P>0.05). In the US imaging features, there had significant differences of border, shape, extracapsular invasion, nodule size, aspect ratio, calcification, parenchyma, cervical lymphadenectasis and the blood supply of nodules(P<0.05), only echo homogenization and rear acoustic attenuation without statistical significance(P>0.05). Serum TSH level were divided into five groups,with the increasing of TSH level, the prevalence rate of malignant nodules should advanced, but the first group had a higher malignancy rate than the second group. A cutoff value of 1.29?U/ml had the highest sensitivity and specificity for diagnosing malignant disease. Among thethyroid carcinoma patients, 87.8% presented with TSH > 1.29?U/ml,compared to only 31.4% in the benign group(P<0.001). we determined that patients with TSH > 1.29?U/ml, had a 15.56-fold greater risk of cancer than a patient with TSH ? 1.29?U/ml(OR 15.66,95% CI1.20–2.23), indicating that the risk of malignant nodules increased. At last,a ROC curve, established the TSH level, US imaging feature combined with preoperative serum TSH level, which respectively had an area under the curve of 0.831,0.912, sensitivity of 87.8% ? 94.4%, specificity of68.6%?87.9%.Conclusion: US image features and preoperative serum TSH level each have diagnostic value of differentiating on thyroid nodules, thus,after the combination of the two, can improve the diagnostic accuracy of benign and malignant thyroid nodules.