Ruiz Franco-Baux J V, Borrego Dorado I, Gómez Camarero P, Rodríguez Rodríguez J R, Vázquez Albertino R J, Navarro González E, Astorga Jiménez R
Servicio de Medicina Nuclear, Hospital Universitario Virgen del Rocio, Sevilla.
Rev Esp Med Nucl. 2005 Jan-Feb;24(1):5-13. doi: 10.1157/13070351.
This study aimed to evaluate the role of Fluorine-18-fluorodeoxyglucose positron emission tomography (PET-FDG) in patients with elevated serum thyroglobulin (hTg) levels where thyroid cancer tissue does not concentrate radioiodine, rendering false-negative results on I-131 scanning.
Whole-body PET imaging using FDG was performed in 54 patients (37 female, 17 male) aged 17-88 years: 45 with papillary tumors and 9 with follicular tumors who were suspected of having recurrent thyroid carcinoma due to elevated thyroglobulin levels (hTg > 2 ng/ml) under thyroid-stimulating hormone (TSH > or = 30 microIU/ml) in whom the iodine scan was negative. All whole body scans were obtained with diagnostic doses (185 MBq). Whole body PET imaging was performed in fasting patients following i.v. administration of 370 MBq FDG while the patients were receiving full thyroid hormone replacement. Before PET, 99mTc methoxyisobutylisonitrile scintigraphy (99mTc-MIBI) was done in 14 patients and morphologic imaging in 26 by CT scan.
Positive PET results confirmed the presence of hypermetabolic foci in 25/54 patients (46.29 %). Positive findings were found for PET-FDG in patients with hTg levels higher than 10 ng/ml receiving full thyroid hormone replacement. 99mTc-MIBI demonstrated lesions in 7/14 patients (50 %). PET-FDG and 99mTc-MIBI had congruent positive results in 4/7 patients. All the lesions found by CT were detected by PET-FDG, while recurrent disease was found in 12/21 patients with previous negative CT.
These results suggest that PET-FDG seems to be a promising tool in the follow-up of thyroid cancer and should be considered in patients suffering from differentiated thyroid cancer with suspected recurrence and/or metastases by elevated thyroglobulin levels, and negative I-131 whole body scans. PET-FDG might be more useful at hTg levels > 10 ng/ml.
本研究旨在评估氟-18-氟脱氧葡萄糖正电子发射断层扫描（PET-FDG）在血清甲状腺球蛋白（hTg）水平升高且甲状腺癌组织不摄取放射性碘，导致I-131扫描出现假阴性结果的患者中的作用。
对54例年龄在17 - 88岁的患者（37例女性，17例男性）进行了使用FDG的全身PET成像：45例乳头状肿瘤患者和9例滤泡状肿瘤患者，这些患者因甲状腺球蛋白水平升高（hTg > 2 ng/ml）且在促甲状腺激素（TSH >或 = 30 μIU/ml）刺激下碘扫描为阴性而怀疑患有复发性甲状腺癌。所有全身扫描均使用诊断剂量（185 MBq）。在患者接受全甲状腺激素替代治疗时，静脉注射370 MBq FDG后，对空腹患者进行全身PET成像。在PET检查前，14例患者进行了99mTc甲氧基异丁基异腈闪烁显像（99mTc-MIBI），26例患者进行了CT形态学成像。
PET阳性结果证实25/54例患者（46.29%）存在高代谢灶。在接受全甲状腺激素替代治疗且hTg水平高于10 ng/ml的患者中，PET-FDG发现了阳性结果。99mTc-MIBI在7/14例患者（50%）中显示有病变。PET-FDG和99mTc-MIBI在4/7例患者中有一致的阳性结果。CT发现的所有病变均被PET-FDG检测到，而在先前CT检查为阴性的21例患者中，12例发现有复发性疾病。
这些结果表明，PET-FDG似乎是甲状腺癌随访中有前景的工具，对于因甲状腺球蛋白水平升高且I-131全身扫描阴性而怀疑有复发和/或转移的分化型甲状腺癌患者应予以考虑。在hTg水平 > 10 ng/ml时，PET-FDG可能更有用。
