Clinicopathologic Characteristics And Predictive Factors For Central Lymph Node Metastasis In 1988 Papillary Thyroid Microcarcinoma Patients

Objective:To determine the pathologic characteristics and predictive factors that increase the neck cental lymph node metastasis(CLNM)in papillary thyroid microcarcinoma(PTMC).Especially,to determine the correlations between the age and the central lymph node metastases at different age cutoffs,and the real relation between age and the central lymph node metastases in papillary thyroid microcarcinomas.Finally,to explain the superiority of the primary tumor diameter(PTD),by comparing the consequences between the central lymph node metastases and the primary tumor diameter(PTD)or the total tumor diameter(TTD)in papillary thyroid microcarcinomas with multifoc ality.Methods:In this retrospective study,clinical and pathologic data were collected from patients who were first diagnosed with PTMC at the Xinjiang Medical University affiliated Tumor Hospital of between January 2010 and March 2016.Chi-square test,the curve of receiver operating characteristic(ROC)and multivariate logistic regression analysis were used to identify the risk factors of the neck central lymph node metastasis.Results:Of all 1988 patients,34.9%had the neck central lymph node metastasis.Multivariate logistic regression analysis indicated that male,age<45 years,the number of focality>3,tumor size>5 mm,microcalcification or microcalcification with calcification,capsular invasion,without thyroiditis,without nodular goiter were independently correlated with the neck cental lymph node metastasis(P<0.05).However,excepting age cutoff of 70 years,age was also independently correlated with the neck cental lymph node metastasis,at different age cutoffs which cuts from 25 to 70 years at 5-years intervals or from 30 to 60 years at 1-years intervals.Comparing with PTD,it was more superiority to regard TTD as the true diameter of the multifocal papillary thyroid microcarcinomas.TTD could reflect more relationship and variation tendency between the tumor size and the central lymph node metastases in papillary thyroid microcarcinomas with multifocality.For patients with a solitary primary tumor,tumor location was independently correlated with the neck cental lymph node metastasis.Unifocal tumor location in the lower third of the thyroid lobe was associated with the highest risk of the neck cental lymph node metastasis(46.8%)(P<0.05).Multifocal tumor location was not associated with the neck cental lymph node metastasis(P=0.211).Conclusions:More aggressive treatment or more frequent follow-up could be considered for patients with unfavorable features(male,age<45 years,the number of focality>3,tumor size>5 mm,microcalcification or microcalcification with calcification,capsular invasion,without thyroiditis,without nodular goiter,unifocal tumor location in the lower third of the thyroid lobe),as these patients may be at an increased risk for the neck cental lymph node metastasis.Then,age at diagnosis,not being a cutoff,only reflects variation tendency and is more superiority regarded as continuous variable in the correlationa study in papillary thyroid microcarcinomas,Finally,comparing with PTD,TTD is the true diameter in papillary thyroid microcarcinomas with multifocality.