Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Nagoya J Med Sci. 2020 May;82(2):205-215. doi: 10.18999/nagjms.82.2.205.
We retrospectively evaluated the frequency of unexpected accumulation of radioactive iodine on the post-therapy whole-body scan (Rx-WBS) after radioactive iodine (RAI) ablation therapy in patients with differentiated thyroid cancer (DTC). We searched our institutional database for Rx-WBSs of DTC patients who underwent RAI ablation or adjuvant therapy between 2012 and 2019. Patients with distant metastasis diagnosed by CT or PET/CT before therapy, and those had previously received RAI therapy were excluded. In total, 293 patients (201 female and 92 male, median age 54 years) were selected. Two nuclear medicine physicians interpreted the Rx-WBS images by determining the visual intensity of radioiodine uptake by the thyroid bed, cervical and mediastinal lymph nodes, lungs, and bone. Clinical features of the patients with and without the metastatic accumulation were compared by chi-square test and median test. Logistic regression analyses were performed to compare the association between the presence of metastatic accumulation and these clinical factors. Eighty-four of 293 patients (28.7%) showed metastatic accumulation. Patients with metastatic RAI accumulation showed a significantly higher frequency of pathological N1 (pN1) and serum thyroglobulin (Tg) > 1.5 ng/ml under TSH stimulation (p = 0.035 and p = 0.031, respectively). Logistic regression analysis indicated that a serum Tg > 1.5 ng/ml was significantly correlated with the presence of metastatic accumulation (odds ratio = 1.985; p = 0.033). In conclusion, Patients with Tg > 1.5 ng/ml were more likely to show metastatic accumulation. In addition, the presence of lymph node metastasis at the initial thyroid surgery was also associated with this unexpected metastatic accumulation.
我们回顾性评估了在分化型甲状腺癌（DTC）患者接受放射性碘（RAI）消融治疗后，治疗后全身扫描（Rx-WBS）中放射性碘意外积聚的频率。我们在我们的机构数据库中搜索了 2012 年至 2019 年间接受 RAI 消融或辅助治疗的 DTC 患者的 Rx-WBS。排除了在治疗前通过 CT 或 PET/CT 诊断出远处转移的患者，以及之前接受过 RAI 治疗的患者。总共选择了 293 名患者（201 名女性和 92 名男性，中位年龄 54 岁）。两名核医学医师通过确定甲状腺床、颈部和纵隔淋巴结、肺部和骨骼中放射性碘摄取的视觉强度来解释 Rx-WBS 图像。通过卡方检验和中位数检验比较有和无转移积聚患者的临床特征。进行逻辑回归分析比较转移性积聚的存在与这些临床因素之间的关联。在 293 名患者中，有 84 名（28.7%）患者出现转移性积聚。转移性 RAI 积聚患者的病理 N1（pN1）和 TSH 刺激下血清甲状腺球蛋白（Tg）>1.5ng/ml 的频率明显更高（p=0.035 和 p=0.031）。逻辑回归分析表明，血清 Tg>1.5ng/ml 与转移性积聚的存在显著相关（优势比=1.985；p=0.033）。总之，Tg>1.5ng/ml 的患者更有可能出现转移性积聚。此外，初始甲状腺手术时淋巴结转移的存在也与这种意外的转移性积聚有关。
