血清Tg测定和^(131)I显像用于分化型甲状腺癌术后随访

A comparative study on between serum Tg analysis and ^(131) scanning in the follow-up of postoperative patients with differentiated thyroid cancer

目的 建立血清甲状腺球蛋白 (Tg)测定的正常分界值 ,以预测分化型甲状腺癌 (DTC)术后有无复发与转移。方法 采用界值特征曲线 ,分析测定 34例DTC未复发者与 5 0例复发者血清Tg值。同时对治疗剂量131I全身显像与血清Tg测定值进行比较。结果 未复发组Tg值明显低于对照组 (P <0 .0 5 ) ,若以血清Tg 8μg/L作为判断界值 ,则 81% (39/ 48例 )的复发与转移患者可被正确预测 ,其诊断DTC复发与转移的灵敏度与特异性分别为 80 .4%和 10 0 %。结论 采用Tg正常分界值 ,可明显提高DTC复发与转移的检出率。

Objective To research and determine the critical value of serum Tg (sTg)in monitoring recurrences or metastases during the follow up of differentiated thyroid cancer (DTC). Methods Serum Tg levels were measured in 82 patients with DTC who had undergone thyroidectomy and 131 I ablation, 34 of them were without recurrences, 48 of them with recurrences and metastases. Receiver Operating Characteristic (ROC) was used to get proper cut off sTg value and to compare the results between therapeutic doses of 131 I used around the study and serum Tg levels of recurrent DTC. Results The sTg levels of non recurrent DTC were evidently lower than those in normal group (P<0.05) and when a cut off value of 8 μg/L was selected, approximately 80% (39/48) of recurrent patients were detected. The sensitivity, specificity of the test for detecting metastases were 80.4% and 100%, respectively. Combining with the 131 I scanning, the two methods can complement each other to achieve maximun sensitivity and reliablity. Conclusion The study suggests that the level of 8 μg/L of sTg can be used as an optimal cut off point to raise the detection rate of recurrences and metastases of DTC patients.