Analysis Of Risk Factors Of Central Lymph Node Metastasis And Establishment Of A Nomogram Model In Papillary Thyroid Carcinoma With Hashimoto’s Thyroiditis

Objective:To study the risk factors of central lymph node metastasis in patients with papillary thyroid carcinoma with Hashimoto’s thyroiditis by analyzing the clinical and ultrasonic image characteristic data.To find and establish a combination of preoperative clinical and ultrasonic image characteristic data.We aim to evaluate the central lymph node metastasis status model of patients with papillary thyroid carcinoma with Hashimoto’s thyroiditis,so as to provide an important basis for surgical decision-making.Methods:The clinical and ultrasonographic features of 207 patients with papillary thyroid carcinoma with Hashimoto’s thyroiditis confirmed by pathology from May2017 to July 2020 were collected.Retrospective analysis included clinical and ultrasonographic features of patients:age,sex,BMI,BRAF gene,Tgab,Tpoab antibody status,multifocality,tumor location,diameter,boundary,calcification,shape,diameter grade.According to the status of lymph node metastasis in the central region,the patients were divided into two groups:non-metastasis group and metastasis group.Univariate analysis was conducted by Mann-Whitney U test,Pearson Chi-square test and Fisher test,multivariate analysis was carried out by binary logistic regression and regression equation was constructed.On this basis,independent risk factors related to lymph node metastasis in the central area were screened out,and a line chart model was established.The accuracy of the nomogram model is evaluated and internally verified by ROC curve and bootstrap method.Results:In this study,the overall rate of central lymph node metastasis was44.93%（93/207）.Univariate analysis showed that age sex,tumor diameter,Tpoab antibody status,tumor location,calcification,aspect ratio greater than 1,shape,tumor diameter>1cm were closely related to central lymph node metastasis.After the above-mentioned factors were included in the binary logistic for multivariate analysis,the results showed that the tumor was located at the lower pole X₁（OR:7.486）,Tpoab antibody negative X₂（OR:2.679）.The diameter of tumor>1cm X₃（OR:4.841）,aspect ratio>1X₄（OR:5.721）,calcification X₅（OR:6.236）,irregular shape X₆（OR:2.623）was an independent risk factor for lymph node metastasis in the central region.The predict the risk probability of lymphnodemetastasisinthecentralarea:P=1/1+exp（-5.329+2.013X₁+2.679X₂+1.577X₃+1.744X₄+1.830X₅+0.964X₆）.Based on this,construct a nomogram model,and use the visual graph to calculate the probability of lymph node metastasis in the central area.Among them,the location and calcification of the tumor had the greatest influence on the central lymph node metastasis,followed by the aspect ratio and diameter grade,and the state and morphology of Tpoab antibody had the least influence.ROC results show that the area under the curve is 0.875,which has certain accuracy and applicability.Conclusion:Negative Tpoab antibody,preoperative ultrasound findings that the tumor is located at the lower pole,calcification,aspect ratio greater than 1,irregular shape,diameter grade larger than 1cm are independent risk factors for central lymph node metastasis in patients with thyroid papillary carcinoma with Hashimoto’s thyroiditis.The nomogram model based on the current research data which can effectively predict the risk of lymph node metastasis in the central area of patients with papillary thyroid carcinoma complicated with Hashimoto’s thyroiditis.It is helpful for clinicians to simply and quickly evaluate the status of lymph node metastasis in the central area before operation and make a better treatment plan.