Hsieh Ching-Jung, Wang Pei-Wen
Division of Endocrinology and Metabolism, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine , Kaohsiung, Taiwan .
Thyroid. 2014 Mar;24(3):488-93. doi: 10.1089/thy.2012.0611. Epub 2013 Nov 13.
To investigate whether elevated and sequential changes in serum antithyroglobulin antibody (TgAb) levels are indicators of recurrence or persistence of papillary thyroid cancer (PTC) in patients with undetectable thyroglobulin.
In 56 patients followed for more than 7 years, we recorded all serum TgAb levels (except the ones determined within one year after (131)I therapy or diagnostic scans) and evaluated their disease status. All patients had undergone total thyroidectomy and remnant ablation by (131)I, and they were positive for TgAb and had undetectable thyroglobulin during follow-up. The sequential changes of TgAb were defined as persistently high, increasing, persistently medium, decreasing, and decreasing to negative. Recurrence or persistence of PTC was defined as active disease as assessed by (131)I scanning, (18)F-fluorodeoxyglucose positron emission tomography, ultrasonography, computed tomography, or surgical examination.
Of the 56 patients enrolled, 10 patients had persistent PTC and 12 patients had recurrent PTC at more than 1 year after total thyroidectomy and (131)I therapy. TgAb was persistently high in 4 patients (3 with active PTC), increasing in 6 patients (4 with active PTC), persistently medium in 16 patients (12 with active PTC), decreasing in 5 patients (none with active PTC), and decreased to negative in 25 patients (3 with active PTC). According to the trend, the patients with persistently high TgAb, increasing TgAb, and persistently medium TgAb had active disease more often (p<0.001). In the multivariable regression analyses, the trend of TgAb change was a strong predictor of PTC activity (p<0.001, R(2)=-0.501). The most common diagnostic procedures performed for active disease were neck ultrasonography (21 patients) followed by (18)F-fluorodeoxyglucose positron emission tomography (11 patients). The patients with autoimmune thyroid disease had better prognoses than did the patients without autoimmune thyroid disease (18% active PTC vs. 53% active PTC, p=0.02).
The presence of TgAb is indicative of an active tumor. Sequential TgAb change is a good predictor of disease prognosis and is helpful for clinical decision making.
探讨血清抗甲状腺球蛋白抗体（TgAb）水平升高及连续变化是否可作为甲状腺球蛋白检测不到的甲状腺乳头状癌（PTC）患者复发或持续存在的指标。
对56例随访超过7年的患者，记录所有血清TgAb水平（131I治疗或诊断性扫描后1年内测定的除外）并评估其疾病状态。所有患者均接受了甲状腺全切术及131I残余消融治疗，随访期间TgAb阳性且甲状腺球蛋白检测不到。TgAb的连续变化定义为持续高、升高、持续中等、降低及降至阴性。PTC复发或持续存在定义为经131I扫描、18F-氟脱氧葡萄糖正电子发射断层扫描、超声、计算机断层扫描或手术检查评估的活动性疾病。
在纳入的56例患者中，10例患者甲状腺全切术及131I治疗后1年以上存在持续性PTC，12例患者存在复发性PTC。4例患者（3例有活动性PTC）TgAb持续高，6例患者（4例有活动性PTC）TgAb升高，16例患者（12例有活动性PTC）TgAb持续中等，5例患者（无活动性PTC）TgAb降低，25例患者（3例有活动性PTC）TgAb降至阴性。根据趋势，TgAb持续高、升高及持续中等的患者更常出现活动性疾病（p<0.001）。在多变量回归分析中，TgAb变化趋势是PTC活动性的有力预测指标（p<0.001，R2=-0.501）。针对活动性疾病最常用的诊断方法是颈部超声检查（21例患者），其次是18F-氟脱氧葡萄糖正电子发射断层扫描（11例患者）。自身免疫性甲状腺疾病患者的预后优于无自身免疫性甲状腺疾病的患者（活动性PTC分别为18%和�3%，p=0.）。
TgAb的存在提示肿瘤处于活动状态。TgAb的连续变化是疾病预后的良好预测指标，有助于临床决策。
