Risk Factors For Recurrence In Follicular Thyroid Carcinoma:a Meta-analysis

Objective: To investigate the risk factors of recurrence in follicular thyroid carcinoma(FTC),and provide evidence for predicting and preventing the recurrence of FTC.Methods: The literatures published before March 2017 were systematic searched in Pub Med?Cochrane Library?Embase?CBM?CNKI and Wan Fang database(up to the date of March,2017),included the literatures related to risk factors for recurrence of FTC,evaluated their methodological quality and extracted data.The Cochrane collaboration's Review Manager 5.3 and Stata 14.0 software were used for Metaanalysis.Dichotomous data were showed by using the odds risk(OR)and 95% CI.Q test and I2 statistics were used to detect heterogeneity among studies,Stata 14.0were used to detect publication bias by Egger linear regression and Harbord test.Single rate of meta-analysis was used to evaluate overall recurrence rate of literatures.Results: A total of 1738 literatures were searched,15 literatures were finally included in this study,involving 1531 FTC patients and 308 were recurrent patients.Metaanalysis showed that the OR and 95%CI of gender,tumor size,cervical lymph node metastases,distant metastases,degree of histologic differentiation and extrathyroid extension were 2.18 [1.54,3.09],0.23 [0.09,0.57],4.76 [2.95,7.69],4.52 [2.40,8.53],0.26 [0.09,0.79],29.11 [2.08,408.30],respectively.Z test showed that there were statistical differences(P<0.0001,0.001,<0.00001,<0.00001,0.02,0.01,respectively),suggested that male,tumor size ?4cm,cervical lymph node metastases,distant metastases,moderate or low histologic differentiation and extrathyroid extension were significantly correlated with the recurrence of FTC.While the OR and 95%CI of age,resection extent,cervical lymph node dissection,degree of vascular invasion,capsule invasion,radioiodine treatment and radiotherapy were 0.35 [0.12,1.06],1.00[0.45,2.26],1.31 [0.33,5.21],6.37 [0.84,48.12],1.50 [0.47,4.77],5.35 [0.59,48.46],1.79 [0.93,3.44],respectively.Z test showed that there were no statistical differences(P>0.05).The sensitivity analysis showed that the OR and 95%CI of age,degree ofvascular invasion,capsular invasion were 0.26 [0.08,0.88],16.06 [2.76,93.33],2.76[1.15,6.60],respectively.Z test showed that there were statistical differences(P=0.03,0.002,0.02,0.008,respectively),suggested that ?45 years old,extensive vascular invasion and positive capsular invasion were also correlated with the recurrence of FTC.Conclusions: This study suggested that risk factors influencing recurrence of FTC include ?45 years old,male,tumor size ?4cm,cervical lymph node metastases,distant metastasis,extensive vascular invasion,positive capsule invasion,moderate or low histologic differentiation and extrathyroid extension.For those patients who have the above risk factors should take an individualized treatment and close follow-up observation,with a view to early detection of tumor recurrence and improve patients' quality of life.