From the Departments of Breast and Endocrine Surgery.
Radiology, and.
Clin Nucl Med. 2018 Jul;43(7):482-485. doi: 10.1097/RLU.0000000000002078.
Age is a prognostic factor for recurrent differentiated thyroid carcinoma (DTC) and may be related to radioactive iodine (RAI) nonavidity. Indications for molecular-targeted drugs (MTDs) are currently limited to RAI-refractory DTC. Demonstrating refractoriness to RAI, mainly indicated by RAI nonavidity, may be a barrier to the introduction of MTDs for elderly patients. The present study was conducted to evaluate the impact of age and histological type on the RAI avidity of recurrent lesions of DTC.
Two hundred fifty-eight patients (189 patients with classic papillary thyroid carcinoma [cPTC], 8 patients with follicular variant of papillary thyroid carcinoma, and 61 patients with follicular thyroid carcinoma), who underwent their first RAI whole-body scanning for recurrent DTC at our institution between 2004 and 2013, were retrospectively studied. Radioactive iodine uptake was determined by visible uptake by metastatic lesion(s) in a diagnostic RAI-whole-body scan.
The prevalence of RAI-avid lung metastases in cPTC indicated a significant, inverse correlation with age (<55 years, 36.2%; ≥55 years, 3%; P < 0.001). By contrast, for follicular thyroid carcinoma, the prevalence of RAI avidity was not influenced by age. Similar tendencies were observed for lymph node metastases.
Radioactive iodine avidity by metastatic lesions of cPTC in elderly patients, especially those older than 55 years, was seldom demonstrated. Adherence to a strategy of restricting MTD administration after confirmation of RAI refractoriness should be revisited for elderly patients. A strategy of omitting RAI treatment should be taken into account when considering age and histological type.
年龄是复发性分化型甲状腺癌（DTC）的预后因素，可能与放射性碘（RAI）摄取无关。分子靶向药物（MTD）的适应证目前仅限于 RAI 难治性 DTC。对 RAI 的耐药性，主要表现为 RAI 摄取无应答，可能是老年患者引入 MTD 的障碍。本研究旨在评估年龄和组织学类型对 DTC 复发性病变 RAI 摄取的影响。
回顾性分析 2004 年至 2013 年间在我院行首次 RAI 全身扫描以诊断复发性 DTC 的 258 例患者（189 例经典型乳头状甲状腺癌[cPTC]，8 例滤泡状甲状腺癌变异型，61 例滤泡状甲状腺癌）。放射性碘摄取通过转移性病变（s）在诊断性 RAI 全身扫描中的可见摄取来确定。
cPTC 中 RAI 摄取阳性的肺转移灶的发生率与年龄呈显著负相关（<55 岁，36.2%；≥55 岁，3%；P<0.001）。相比之下，滤泡状甲状腺癌的 RAI 摄取率不受年龄影响。淋巴结转移也有类似的趋势。
老年患者（尤其是年龄大于 55 岁的患者）cPTC 转移灶的 RAI 摄取性很少见。对于老年患者，在确认 RAI 耐药后，应重新考虑限制 MTD 给药的策略。在考虑年龄和组织学类型时，应考虑省略 RAI 治疗的策略。
