Distant metastasis (DM) is the dominant negative prognosis for thyroid carcinoma. Radioactive iodine (RAI) therapy serves as an effective treatment for thyroid carcinoma. However, resistance to RAI occurs in patients with DMs. The present study aims to discriminate patients who may benefit from RAI. We extracted patients with thyroid cancer in the Surveillance, Epidemiology, and End Results program and analyzed thyroid cancer-specific survival after radiotherapy based on age and grade subgroups. A total of 1608 patients having DMs were eligible, including 521 (32.4%) cases with bone metastasis, 90 (5.6%) cases with brain metastasis, 158 (9.8%) cases with liver metastasis, 995 (61.9%) cases with lung metastasis, and 50 (3.1%) cases with other metastases. Advanced age, poor differentiation, follicular carcinoma, lymphatic metastasis, tumor size >10 mm, and extracapsular invasion are associated with pulmonary metastases. With respect to patients with DM, RAI therapy improved the survival in the age <45 years group and the well-/moderately differentiated group. For patients with pulmonary metastasis, RAI improved the survival in the higher grade group but did not have a strong effect in the better grade group. Our data indicate that the disparity of metastatic sites has different risk factors. Similarly, this finding indicates that RAI should be precisely applied to patients who undergo DM but are young and have well-/moderately differentiated tumors and may improve survival in pulmonary metastasis patients with poor grade tumors.

中文翻译：

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甲状腺癌远处转移患者的放射性碘治疗：基于SEER的研究。

远处转移（DM）是甲状腺癌的主要阴性预后。放射性碘（RAI）治疗可有效治疗甲状腺癌。但是，DM患者会出现对RAI的耐药性。本研究旨在区分可能受益于RAI的患者。我们在“监视，流行病学和最终结果”程序中提取了甲状腺癌患者，并根据年龄和等级分组分析了放疗后甲状腺癌的特异性存活率。符合条件的糖尿病患者共1608例，包括骨转移521例（32.4％），脑转移90例（5.6％），肝转移158例（9.8％），肺转移995例（61.9％） ，另有50例（3.1％）发生其他转移。高龄，分化差，滤泡癌，淋巴结转移，肿瘤大小> 10 mm和囊外侵犯与肺转移有关。对于DM患者，RAI治疗改善了<45岁组和高/中分化组的生存率。对于有肺转移的患者，RAI改善了高年级组的生存率，但对高年级组没有明显的作用。我们的数据表明转移部位的差异具有不同的危险因素。同样，这一发现表明，RAI应该精确地应用于患有DM但年轻且具有良好/中度分化的肿瘤的患者，并且可能会改善具有低度肿瘤的肺转移患者的生存率。45岁组和高/中度分化组。对于有肺转移的患者，RAI改善了高年级组的生存率，但对高年级组没有明显的作用。我们的数据表明转移部位的差异具有不同的危险因素。同样，这一发现表明，RAI应该精确地应用于患有DM但年轻且具有良好/中度分化的肿瘤的患者，并且可能会改善具有低度肿瘤的肺转移患者的生存率。45岁组和高/中度分化组。对于有肺转移的患者，RAI改善了高年级组的生存率，但对高年级组没有明显的作用。我们的数据表明转移部位的差异具有不同的危险因素。同样，该发现表明，RAI应该精确地应用于患有DM但年轻且肿瘤分化良好/中度分化的患者，并可以改善恶性程度低的肺转移患者的生存率。