Influence Factors Of Locally Advanced Differentiated Thyroid Cancer And The Effect Of ¹³¹I On Its Efficacy And Overall Survival

Part 1 Influence factors of extrathyroidal extension of differentiated thyroid cancerObjectivesBe aims to analyze the influence factors of population characteristics,surgical and pathological characteristics on extrathyroidal extension of differentiated thyroid cancer.Materials and MethodsWe performed a retrospective analysis on patients who underwent initial RAI therapy between January 2014 and December 2016.They were divided into three groups based on the extent of extrathyroidal extension of differentiated thyroid cancer.Univariate and multivariate analysis were performed Comparisons among groups were performed using the chi-square test or Fisher exact test Any category with a P value<0.05 on univariate analysis was included in the multivariate analysis.Data were analyzed using IBM SPSS Statistics 20 software.ResultsOf 428 patients,the mean age of the patients was 41.5 years,and 69.6%were female.Approximately 95%of the patients were PTC.The mean primary tumor size was 1.95cm.56.5%of them were multifocal lesions and 89.0%of the patients had no distant metastasis,382 patients(89.2%)receiving lymph node dissection.Approximately 68%of the patients were minimal extrathyroidal extension(perithyroid tissues),19.9%of the patients were gross extrathyroidal extension(sternohyoid,sternothyroid,thyrohyoid,omohyoid muscles).The recurrent laryngeal nerve was the most common invasive organ,accounting for 5.7%(25 cases),trachea and esophagus accounted for 4.0%(18 cases)and 3.7%(16 cases),respectively.Group A had 299 cases(69.9%),Group B had 85 cases(19.9%),and Group C had 44 cases(10.3%).There were statistical significant difference in age,histology,primary tumor size and distant metastases among the three groups.In Ordinal logistics regression analysis,it showed that age and primary tumor size were independent risk factors(p=0.002,OR=2.082,95%CI:1.321-1.272;P=0.015,OR=3.064c,95%IC:1.239-7.575),respectively.ConclusionThe extent of extrathyroidal extension of differentiate thyroid carcinoma is affected by age,primary tumor size.The extrathyroidal extension of DTC patients with older age(>45Y)or large primary tumor size(>4cm)tend to more serious.Part2 The efficacy of 131Ⅰ therapy and overall survival of locally advanced differentiated thyroid cancerObjectivesThis study aims to analyze evaluate the efficacy of 131I therapy and overall survival of locally advanced differentiated thyroid cancer.Materials and MethodsWe performed a retrospective review of patients with locally advanced diferentiated thyroid cancer between January 2007 and December 2016 in zhujiang hospital.We assessed OS and LPFS using the Kaplan-Meier method and performed survival analysis using Cox proportional hazard models.Univariate and multivariate analyses were performed.Any category with a P value<.05 on univariate analysis was included in the multivariate analysis.Data were analyzed using IBM SPSS Statistics 20 software.ResultsOf 41 patients.48.8%of the patients were female.Approximately 87.8%of the patients were PTC,no lymph node dissection was performed in 46.3%of patients.The median primary tumor size was 2.7cm.96.2%of the patients had lung metastasis.The median follow-up were 72 months.All the patients were treated with RAI,and the median cumulative 131I doses was 400mCi.However,61.0%of the patients had poor affinity for radioactive iodine.In multivariate analysis,the affinity of gross lesions of locally advanced DTC for radioactive iodine was independent risk factor of LPFS during RAI(HR:7.698,95%CI:1.537-38.568);For OS,the degree of aerodigestive tract invasion(HR:3.925,95%CI:1.016-15.166,P=0.047),the affinity of gross lesions of locally advanced DTC(HR:7.331,95%CI:1.174-45.786,P=0.033),the cumulative 131I doses(HR:0.132,95%CI:0.032-0.545,P=0.005),and the therapy approach(HR:0.121,95%CI:0.027-0.538,P=0.006)were independent risk factors.ConclusionOur study showed that radioactive iodine therapy for locally advanced differentiated thyroid cancer patients with radioactive iodine avid can not only have a certain effect on the control of locally advanced thyroid cancer in the short term,and prolong the LPFS of patients,but also prolong the overall survival.However,for the long-term outcome of these patients,combination therapy is more likely to prolong overall survival than iodine alone.