A Clinical Study On Prophylactic Central Lymph Node Dissection In Early CN0 Papillary Thyroid Carcinoma

[OBJECTIVE]As the most common type of thyroid carcinoma,papillary thyroid carcinoma(PTC)has a increasingly incidence in recent years around the world.Central lymph node dissection is an important part of its treatment.At present,all guidelines suggest that the central region with malignant lymph node metastasis requires therapeutic dissection.But for patients without clear evidence of malignant lymph node metastasis,arguments occur between different guidelines.In this study,we explore the risk factors and construct a predictive model for occult central lymph node metastasis in early cNO PTC,combining with the complication rate of PCLND,to provide the decision basis of PCLND.[METHODS]Clinical data of 454 early cNO PTC patients was retrospectively analyzed.The categorical variables univariate analysis was performed by chi-square test,and the risk factors analysis was performed by logistic regression analysis.A predictive model for occult central lymph node metastasis was constructed on the independent risk factors.The incidence of postoperative temporary complications was calculated,and a meta-analysis was built to compare their incidence of complications with this study.[RESULT]The proportion of males,age≤45,tumor diameter>lcm,multifocal cancer,bilateral cancer,capsular invasion,ultrasonographic microcalcifications,and family history of thyroid cancer in the positive group was significantly higher than that in the positive group.Male,age≤45,diameter>1cm,and formation of microcalcifications were independent risk factors for occult central lymph node metastasis.The prediction model of occult central lymph node metastasis was established according to the independent risk factors:Logit(P)=-1.735-0.717×sex+0.442×age+1.245×diameter+1.349×microcalcifications.The ROC curve was used to verify the application value of the prediction model,and the area under the curve(AUC)was 0.745.According to meta-analysis,our PCLND did not increase the incidence of complications.[CONCLUSION]1.Male,age≤45,tumor diameter>lcm,ultrasonographic microcalcifications were independent risk factors for central lymph node metastasis in early cN0 PTC.2.A prediction model for occult central lymph node metastasis was established:Logit(P)=-1.735-0.717 x gender+0.442×age+1.245 × diameter+1.349 × microcalcifications.After test,the model has good prediction effect and practical value.3.The model should be used to calculate the probability of oceult central lymph node metastasis before surgery.The larger the P-value is,the higher the risk of lymph node metastasis will be,and PCLND should be performed for these patients.4.The incidence of temporary postoperative complications in our study was lower than other studies,which showing surgery with good skills would not increase the temporary incidence after PCLND.Thus,for the possibility of occult central lymph node metastasis,PCLND should be actively performed in all patients with early cN0 PTC to remove possible occult malignant lymph nodes.