The Comparative Research Of Thyroglobin With Three Different Methods In DTC Follow-up

For Differentiated thyroid cancer (Differentiated thyroid cancer, DTC)，thyroglobulin (Thyroglobulin, Tg)，which is synthesized and secreted by primarytumors and metastatic lesions.A major determinant of Tg concentration level: size of thyroid，thyroid damage(such as biopsy, trauma and inflammation)，hormone (TSH)，anti thyroglobulinantibody (TgAb) and different methodology. At present，in hospital laboratory,Various methods are used to detect Tg, TgAb, the main methods are:radioimmunoassay (Radioimmunoassay, RIA) and immune measurement analysismethod, the latter mainly includes the chemiluminescence Immunoassay(Chemiluminescence Immunoassay Assay, CLIA) and electrochemical luminescenceImmunoassay (Electrochemiluminescent Immunoassay, ECLIA), etc.differenthospital has different methods. To eliminate the interference factors of TgAb,thisstudy selected the negative patients for TgAb,and then detected Tg by three differentmethods. ObjectiveTo research the Tg values by CLIA and RIA methods,and find out whether theyare consistent with ECLIA detection.If not consistent,finding the critical value ofTg,for ECLIA or RIA.Materials and MethodsOf all cases of ECLIA detection results, Screening TgAb negative (TgAb <115IU/ml), to eliminate TgAb interference with the results of the study.200cases of patients with DTC, after thyroid surgery and131I treatment at leastsix months in nuclear medicine clinic at the first affiliated hospital of zhengzhouuniversity in2012-2013.In the follow-up，all patients were taken Tg, TgAb by theECLIA method and neck ultrasound, SPECT/CT fusion imaging. TSH stimulatedstate into three groups, clinical cure, suspicious cure group and not cure group;T4suppression condition is divided into two groups, clinical cure and suspectedrecurrence/metastasis group.To detect all serum Tg values of T4suppression condition and TSH stimulatedstate.Take low concentration mixed with high concentrations of Tg in serumsamples,tested and repeated10times by ECLIA、CLIA and RIA，Calculate eachmeasurement the coefficient of variation. ECLIA and CLIA, ECLIA and RIAintraclass correlation coefficient is studied, If the result is not consistent, find out thecorresponding Tg values.Results1．Comparing the Precision between ECLIA and CLIA and RIA: ECLIAprecision is best, the second is CLIA method, RIA method is the worst.2．ECLIA and CLIA, ECLIA and RIA two factors mixed effect model of theICC:CLIA and ECLIA ICC value is0.28, the results between the two is consistent,although the results have a relatively low level of consistency.3．For ECLIA and CLIA，they are consistent. 4．For RIA，in the TSH stimulated state，the critical value of Tg Correspondingto the clinical cure group reference range for <0.8ng/ml, suspicious for clinical curegroup<2.6ng/ml, no cure for>2.6ng/ml.5．For RIA，in the TSH stimulated state，the critical value of Tg Correspondingto the clinical cure group reference range for<0.18ng/ml, suspected recurrence/metastasis group was>0.18ng/ml.ConclusionTg is an important tumor marker of DTC in the follow up, different Tg testresults will mean different prognosis. Different methods there may be has differenttesting results.measurement results are consistent between ECLIA-CLIA,inconsistent between ECLIA and RIA. If test results are not equivalent, theTg cutoff value is not the same, different cut-off value range is more advantageousfor different hospitals in the follow-up.