Clinical And Pathological Features Of Papillary Thyroid Carcinoma With Chronic Lymphocytic Thyroiditis And Risk Factors For Lymph Node Metastasis

Objective:To summarize clinical and pathological features of papillary thyroid carcinoma(PTC)coexistent with Chronic Lymphocytic Thyroiditis(CLT)and investigate risk factors for lymph node metastasis.Methods:The medical records of 4264 consecutive PTC patients who received surgical treatment from Oct.2013 to Oct.2015 in Peking Union Medical College Hospital were reviewed.Univariate and multivariate analysis were performed to indentify specific clinical and pathological features of PTC with CLT and risk factors for lymph node metastasis and high volume metastasis.Results:In all 4265 cases,there were 3059 papillary thyroid microcarcinoma(PTMC)(71.7%).In 1010 PTC patients(23.7%)with CLT,there were 909(90%)female patients,624 cases with multifocal lesions(61.8%),422 cases with Extrathyroid extension(41.8%),429 cases with lymph node metastasis(42.5%),and 133 cases with metastatic lymph nodes(LNs)≧6(13.2%);with a median age of 43 years and with a median tumor size of 0.8cm.Patients with CLT were female prefered(90.0% vs 70.2%;P <0.001),younger median age(43 vs 44 years;P =0.001),and lower incidence of LNM(42.5% vs 50.9%;P <0.001).CLT was not associated with tumor size,multifocal lesions,extrathyroid extension and metastatic LNs≧6(0.8cm vs 0.7cm,61.8% vs 62.9%,41.8% vs 42.1% and 13.2% vs 14.8%,respectively,all P>0.05).In multivariate analysis,CLT was demonstrated as an independent protective factor for lymph node metastasis(OR=0.713,95%CI=0.609-0.835,P<0.001).In PTC patients with lymph node metastasis,CLT was not associated with metastatic number(3 vs 3,P=0.300).Conclusion:In PTC coexistent with CLT patients,female and younger age were prefered and lower incidence of LNM were demonstrated.CLT is an independent protective factor for LNM in PTC patients.But in patients with LNM,the metastatic number were not decreased with CLT.