Rosário Pedro W S, Tavares Wilson C, Barroso Alvaro L, Rezende Leonardo L, Padrão Eduardo L, Purisch Saulo
Departamento de Tireóide, Serviço de Endocrinologia, Santa Casa Belo Horizonte, MG, Brazil.
Arq Bras Endocrinol Metabol. 2008 Feb;52(1):114-9. doi: 10.1590/s0004-27302008000100016.
Computed tomography (CT or CAT Scan) of the chest is more sensitive than radiography in the detection of lung metastases of differentiated thyroid cancer (DTC), but little information is available regarding the aggregated value of this method. The present study evaluated the response of patients with lung metastases of DTC not apparent on radiography to treatment with 131I and the value of CT in these cases. Twenty-five patients with lung metastases not apparent on radiography, who initially received 100-200 mCi I151, were evaluated and those presenting pulmonary uptake on post-therapy WBS were submitted to a new treatment after 6 to 12 months, and so on. The chance of detection of pulmonary uptake on post-therapy WBS did not differ between patients with negative and positive CT (100% versus 91.5%). Mean serum Tg levels were higher in patients with positive CT (108 ng/ml versus 52 ng/ml). Negative post-therapy WBS was achieved in 82% of patients with positive CT and in 92.3% with negative CT and the cumulative I131 activity necessary to achieve this outcome did not differ between the two groups (mean=300 mCi). Stimulated Tg was undetectable in 47% of patients with negative CT at the end of treatment, but in none of the patients whose CT continued to be positive. In patients with elevated Tg, the CT result apparently did not change the indication of therapy or the I131 activity to be administered. In cases with lung metastases, the persistence of micronodules on CT was associated with the persistence of detectable Tg in patients presenting negative post-therapy WBS.
计算机断层扫描（CT或CAT扫描）在检测分化型甲状腺癌（DTC）的肺转移方面比X线摄影更敏感，但关于该方法的综合价值的信息较少。本研究评估了X线摄影未显示的DTC肺转移患者对131I治疗的反应以及CT在这些病例中的价值。对25例X线摄影未显示肺转移且最初接受100 - 200 mCi I151治疗的患者进行评估，那些在治疗后全身骨显像（WBS）上出现肺部摄取的患者在6至12个月后接受新的治疗，依此类推。治疗后WBS上检测到肺部摄取的几率在CT阴性和阳性的患者之间没有差异（100%对91.5%）。CT阳性的患者平均血清Tg水平较高（108 ng/ml对52 ng/ml）。CT阳性的患者中有82%实现了治疗后WBS阴性，CT阴性的患者中有92.3%实现了治疗后WBS阴性，实现这一结果所需的累积I131活性在两组之间没有差异（平均 = 300 mCi）。治疗结束时，CT阴性的患者中有47%刺激Tg检测不到，但CT持续阳性的患者中无一例检测不到。在Tg升高的患者中，CT结果显然没有改变治疗指征或要给予的I131活性。在有肺转移的病例中，治疗后WBS阴性的患者中，CT上微小结节的持续存在与可检测到的Tg的持续存在相关。
