诊断性^(131)Ⅰ扫描在不明原因高甲状腺球蛋白血症PTC患者处置中的价值

The value of diagnostic ^(131)Ⅰ scan in PTC patients with unexplained hyperthyroglobulinemia

目的:探索诊断性^(131)Ⅰ扫描(diagnostic ^(131)Ⅰ scan,Dx)在不明原因高甲状腺球蛋白(thyroglobulin,Tg)血症甲状腺乳头状癌(papillary carcinoma of the thyroid,PTC)全切术后患者临床处置中的潜在价值。方法:连续纳入2019年3月—2022年2月收治的血清促甲状腺激素(thyroid stimulating hormone,TSH)抑制性Tg>1 ng/mL且无残甲和残留/复发/转移病灶影像学证据的PTC患者。患者口服74 MBq ^(131)Ⅰ后24 h行Dx,当平面显像诊断不明确时立即加行单光子发射计算机体层摄影(single photon emission computed tomography,SPECT)/计算机体层成像(computed tomography,CT)。根据Dx结果等信息明确^(131)Ⅰ治疗目的后即给予患者口服治疗剂量^(131)Ⅰ,3 d后行治疗后全身扫描(post-therapeutic whole-body scan,Rx)。结果:在共67例不明原因高Tg血症PTC患者中,Dx阳性患者有8例(11.9%),Dx与Rx的结果匹配度达97.0%,Dx阴性预测值为94.9%。Dx阳性患者中,6例为颈淋巴结转移瘤,2例为纵隔淋巴结转移瘤。在随访终点时表现为生化缓解、稳定及进展的比例分别为87.5%(7/8)、12.5%(1/8)及0.0%(0/8)。除去1例转靶向治疗患者,剩余58例Dx阴性患者在随访终点时表现为生化缓解、稳定及进展的比例分别占79.3%(46/58)、12.1%(7/58)及8.6%(5/58),两组患者生化疗效差异无统计学意义(P=0.542)。结论:在不明原因高Tg血症PTC患者中,Dx与Rx具有高度一致性。前者可通过检出或排除摄碘PTC病灶明确^(131)Ⅰ治疗目的并保证良好疗效。

Objective:To evaluate the potential role of diagnostic ^(131)Ⅰ scan(Dx)in the managment of totally thyroidectomized papillary carcinoma of the thyroid(PTC)in patients with unexplained hyperthyroglobulinemia.Methods:Totally thyroidectomized PTC patients with suppressed thyroglobulin levels higher than 1 ng/mL and no radiographic evidence of thyroid remnant or percistent/recurrent/metastatic disease were consecutively enrolled from March 2019 to February 2022.A Dx of spot imaging of 10 min covering from cranial base to transverse septum was performed 24 h after an oral administration of ^(131)Ⅰ(74 MBq).Single photon emission computed tomography(SPECT)/computed tomography(CT)was immediately added if planar imaging showed inconclusive findings(the localization of lesions accumulating ^(131)Ⅰ was unclear or a malignant lesion could not be ruled out).A therapeutic activity of ^(131)Ⅰ was prescribed immediately after the goal of treatment was clarified by Dx.Three days later,a planar post-therapeutic whole-body scan(Rx)was conducted with SPECT/CT fusion imaging when needed.Results:In total of 67 PTC patients with unexplained hyperthyroglobulinemia,8(11.9%)of patients were identified with positive Dx,with a coincidence rate of 97.0%between Dx and Rx and a negative predictive value of 94.9%.In patients with Dx-postive,two and six were identified with mediastinal and cervical lymph node metastasis,repectively.Biochemical remssion,stablization and progression were 87.5%(7/8),12.5%(1/8),and 0.0%(0/8),respectively.After the exclusion of one patient who switched to targeted therapy,biochemical remission,stabilization,and progression were achieved in 79.3%(46/58),12.1%(7/58)and 8.6%(5/58)of 58 patients with negative Dx,respectively.No significant difference in biochemical response was found in the two groups(P=0.542).Conclusion:The findings of Dx is highly consistent with those of Rx in totally thyroidectomized PTC patients with unexplained hyperthyroglobulinemia.Radiodine-avid focis were detected or excluded,which is helpful to clarify the purpose of treatment,warranting therapeutic response.