Robbins Richard J, Chon Jajin Thomas, Fleisher Martin, Larson Steve M, Tuttle R Michael
Endocrinology Service, Department of Medicine, Memorial Hospital for Cancer and Allied Diseases, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.
J Clin Endocrinol Metab. 2002 Jul;87(7):3242-7. doi: 10.1210/jcem.87.7.8702.
The serum thyroglobulin (Tg) response to elevated TSH is one of the most sensitive indexes of residual thyroid carcinoma. We have explored the possibility that this test alone would be sufficient to detect residual thyroid carcinoma in thyroid cancer patients after total thyroidectomy and radioiodine remnant ablation. We used recombinant human TSH (rhTSH) to elevate serum TSH, rather than withdraw the patients from thyroid hormone. Routine evaluations, including diagnostic radioiodine whole body scans (DxWBS) and serum Tg, were performed on 366 patients after preparation by rhTSH, over a 2-yr interval. A retrospective analysis of the data from these patients revealed that 76% of those whose stimulated Tg rose to more than 2 microg/liter had evidence for residual thyroid carcinoma, whereas the same was true for only 13% of those whose stimulated Tg was 2 microg/liter or less. Using risk group stratification, we analyzed outcomes in a low risk subset (which excluded patients with elevated Tg levels on suppression, known metastatic disease, and clinical or histological evidence of aggressive disease). In this low risk group, we found that a stimulated Tg of 2 microg/liter or less had a 91.7% negative predictive value. No low risk patient who had had a prior negative DxWBS and a stimulated Tg of 2 microg/liter or less had any evidence of residual thyroid carcinoma. We conclude that the stimulated Tg alone is not sufficient by itself to screen unselected patients, but that it may be sufficient in low risk patients, especially those who have had a prior negative DxWBS.
血清甲状腺球蛋白（Tg）对促甲状腺激素（TSH）升高的反应是残留甲状腺癌最敏感的指标之一。我们探讨了仅通过该项检测就足以在甲状腺癌患者全甲状腺切除及放射性碘残留消融术后检测出残留甲状腺癌的可能性。我们使用重组人促甲状腺激素（rhTSH）来升高血清TSH，而不是让患者停用甲状腺激素。在2年的时间里，对366例经rhTSH准备后的患者进行了常规评估，包括诊断性放射性碘全身扫描（DxWBS）和血清Tg检测。对这些患者的数据进行回顾性分析发现，刺激后Tg升高至超过2μg/升的患者中，76%有残留甲状腺癌的证据，而刺激后Tg为2μg/升或更低的患者中只有13%有同样的情况。通过风险组分层，我们分析了低风险亚组（排除了抑制状态下Tg水平升高、已知转移性疾病以及侵袭性疾病的临床或组织学证据的患者）的结果。在这个低风险组中，我们发现刺激后Tg为2μg/升或更低时，阴性预测值为91.7%。没有一位既往DxWBS阴性且刺激后Tg为2μg/升或更低的低风险患者有残留甲状腺癌的任何证据。我们得出结论，仅刺激后Tg本身不足以筛查所有患者，但在低风险患者中可能足够，尤其是那些既往DxWBS阴性的患者。
