Hsu Chung-Huei, Liu Ren-Shyan, Wu Chih-Hsiung, Chen Su-Mei, Shih Li-Sun
Departments of Nuclear Medicine and Internal Medicine, Taipei Medical University Hospital, 252 Wu-Hsing Street, Taipei, Taiwan.
J Formos Med Assoc. 2002 Jul;101(7):459-67.
18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a relatively new modality in the follow-up of patients with differentiated thyroid cancer (DTC) who have undergone total thyroidectomy and postoperative radioiodine therapy. The aim of this study was to assess the diagnostic value of FDG-PET, comparing it with 131I whole-body scan (WBS) and 201Tl WBS.
Fifteen selected patients with local invasive and/or aggressive DTC were included in this study. The follow-up period ranged from 1 to 12 years, with a mean +/- standard error of 6 +/- 3 years. FDG-PET was performed when patients were still receiving thyroxin therapy.
In the cervical region, residual cancer in two patients was demonstrated by FDG-PET, but could not be detected using 131I WBS or 201Tl WBS. Pathology of the surgical specimen showed dedifferentiation of thyroid cancer in one of these patients. Metastatic cervical lymph nodes were detected using FDG-PET in three patients, but in only one patient using 131I WBS and in another one patient using 201Tl WBS. Mediastinal metastases were detected using FDG-PET in three patients, 131I WBS in two patients, and 201Tl WBS in one patient. Diffuse lung metastasis was detected only by 131I WBS in two patients. The use of FDG-PET in conjunction with computerized tomography provided useful diagnostic information about small nodular lesions of the lung which could not be localized by 131I WBS or 201Tl WBS in three patients. In skeletal metastases, 131I WBS detected more metastatic lesions than FDG-PET or 201Tl WBS, especially when the lesions were located in the pelvis.
In the follow-up evaluation of patients with post-therapy DTC, FDG-PET was useful for detecting dedifferentiated lesions and was superior to 131I WBS in detecting residual cervical or mediastinal lesions and suspected small metastatic foci in the lung. FDG-PET was inferior to 131I WBS in detecting diffuse lung metastases and distant bone metastases.
18F-氟脱氧葡萄糖正电子发射断层扫描（FDG-PET）是一种相对较新的检查方式，用于对已接受甲状腺全切术及术后放射性碘治疗的分化型甲状腺癌（DTC）患者进行随访。本研究旨在评估FDG-PET的诊断价值，并将其与131I全身扫描（WBS）及201Tl WBS进行比较。
本研究纳入了15例经挑选的局部浸润性和/或侵袭性DTC患者。随访期为1至12年，平均±标准误为6±3年。在患者仍接受甲状腺素治疗时进行FDG-PET检查。
在颈部区域，FDG-PET显示2例患者存在残留癌，但131I WBS或201Tl WBS未检测到。其中1例患者手术标本的病理显示甲状腺癌去分化。3例患者通过FDG-PET检测到颈部转移淋巴结，但131I WBS仅在1例患者中检测到，201Tl WBS在另1例患者中检测到。3例患者通过FDG-PET检测到纵隔转移，2例患者通过131I WBS检测到，1例患者通过201Tl WBS检测到。2例患者仅通过131I WBS检测到弥漫性肺转移。在3例患者中，将FDG-PET与计算机断层扫描相结合，提供了有关肺部小结节病变的有用诊断信息，而这些病变无法通过131I WBS或201Tl WBS定位。在骨转移方面，131I WBS检测到的转移灶比FDG-PET或201Tl WBS更多，尤其是当病变位于骨盆时。
在治疗后DTC患者的随访评估中，FDG-PET有助于检测去分化病变，在检测残留颈部或纵隔病变以及肺部可疑小转移灶方面优于131I WBS。在检测弥漫性肺转移和远处骨转移方面，FDG-PET不如131I WBS。
