分化型甲状腺癌术后^（131）I清甲治疗对甲状旁腺功能的影响

目的：观察分化型甲状腺癌切除术后131I清甲治疗对甲状旁腺功能的影响。方法：：对174例（女116,男58）分化型甲状腺癌术后行131I清甲治疗的患者行血清甲状旁腺素（parathyroid hormone,PTH）检测,平均年龄（43.50±14.02）岁。血清PTH检测分四个阶段进行,分别为首次131I清甲治疗前（阶段Ⅰ）,首次131I清甲治疗后3个月（阶段Ⅱ）、6个月（阶段Ⅲ）和9个月（阶段Ⅳ）。174例患者均于阶段I检测后第2d行首次131I清甲治疗,61例患者于阶段Ⅳ检测后第2d行再次131I治疗。血清PTH测定均采用放射免疫分析,正常值为（5～20）ng/dl,PTH检测值低于5ng/dl认定为甲状旁腺功能减退,PTH检测值低于正常范围持续时间超过6个月,认定为持续性甲状旁腺功能减退,6个月内恢复正常,则认定为暂时性甲状旁腺功能减退。每个阶段中发现的甲状旁腺功能减退病例均以病例数（n）和发生率（%）表示,各阶段中PTH检测值均以x珋±s表示,各阶段间PTH值比较采用ANOVA分析,P〈0.05认为差异有统计学意义。结果：①阶段Ⅰ～Ⅳ中各发现68例（39.08%）,26例（14.94%）,16例（12.50%）和13例（15.12%）甲状旁腺功能减退。持续性甲状旁腺功能减退共发现2例,均产生于阶段Ⅰ。②阶段Ⅰ～Ⅳ所发现的甲状旁腺功能减退患者的PTH检测值分别为2.38±1.39,1.94±1.16,2.10±1.29和2.44±1.20ng/dl。经ANOVA分析,各阶段间PTH水平无明显统计学差异,F=0.863,P〉0.05。结论：分化型甲状腺癌切除术后131I清甲治疗会导致甲状旁腺功能减退,其发生可能与残余甲状腺内放射性131I对甲状旁腺产生的辐射损伤有关,其程度与手术所引起的无明显差异,其发生时间在131I清甲治疗后的较长时间内都有可能发生。所以,分化型甲状腺癌术后患者在131I清甲治疗后应定期复查血清PTH,以期及时发现甲状旁腺功能减退。

Effect of Radioiodine Remnant Ablation on Function of Parathyroid in Post-surgical Differentiated Thyroid Cancer Patients

Objective To investigate whether the radioiodine remnant ablation(RRA) would lead to HPT.Methods There were 174 post-thyroidectomy patients who underwent radioactive 131I ablation in our department between 2011 and 2012.The PTH level was examined with RIA from phase Ⅰ to phase Ⅳ every 3 months.174 patients underwent the first RRA one day after the first phase PTH test and 61 patients underwent the second RRA one day after the fourth phase PTH test.The normal range of PTH level was 5-20ng/dl.PTH level under 5ng/dl was defined to be HPT.HPT persisting more than 6 months was defined to be permanent HPT,or it would be defined to be transient ones.The incidence of HPT after the RRA was expressed as case number(n) and percentage(%).The PTH value was expressed as mean±SD.The difference of PTH level in each phase was compared by ANOVA with SPSS 13.0.Results 1.68(39.08%),26(14.94%),16(12.50%) and 13 cases of PTH deficiency were found from phase Ⅰ to phase Ⅳ.Two cases of permanent HPT were all from phase I.2.The PTH level of patients with HPT in each phase was 2.38±1.39,1.94±1.16,2.10±1.29 and 2.44±1.20ng/dl respectively.By ANOVA,the difference of their PTH level between each phases has no statistical significance,P>0.05.Conclusion HPT could be caused not only by the total thyroidectomy but also by the RRA in DTC patients.Radiation injury of the parathyroid maybe cause by the  particles emitted from the neighboring thyroid which accumulates radioiodine during the RRA.Whatever,once HPT occurs,its severity is as same as that of thyroidectomy related HPT.And this type of HPT could be found long periods after the RRA.So,it is necessary to periodically repeat PTH examinations in DTC patients after the RRA to detect HPT in time.