Rodrigues Margarida, Traub-Weidinger Tatjana, Leimer Maria, Li Shuren, Andreae Fritz, Angelberger Peter, Dudczak Robert, Virgolini Irene
Institute of Nuclear Medicine, Lainz Hospital, Vienna, Austria.
Eur J Nucl Med Mol Imaging. 2005 Oct;32(10):1144-51. doi: 10.1007/s00259-005-1820-1. Epub 2005 May 21.
Radioiodine-negative thyroid cancer presents diagnostic and therapeutic difficulties, warranting the implementation of new imaging and treatment strategies. The purpose of this study was twofold. First, we investigated in vitro the binding characteristics of 111In-DOTA-lanreotide (111In-DOTA-LAN) and 111In-DOTA-D: Phe1-Tyr3-octreotide (111In-DOTA-TOC) to cells derived from differentiated thyroid cancer (DTC). Second, we evaluated the value of somatostatin receptor (SSTR) scintigraphy with these radioligands, as compared with 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET), for the detection of tumour lesions in DTC patients.
Binding of 111In-DOTA-LAN and 111In-DOTA-TOC to cells isolated from surgically removed thyroid tissue was evaluated in vitro by performing saturation and displacement studies. Eighteen DTC patients with elevated thyroglobulin (12 radioiodine-negative, six radioiodine-positive) were investigated with 111In-DOTA-LAN, 111In-DOTA-TOC and 18F-FDG PET scans.
Large numbers of SSTR binding sites for 111In-DOTA-LAN and 111In-DOTA-TOC were found on the cells investigated. Both SSTR radioligands exhibited a high binding affinity for these SSTR binding sites. 111In-DOTA-LAN and 111In-DOTA-TOC scintigraphy detected 37 and 33 lesions, respectively, in 17 (94%) patients each, whereas 18F-FDG PET revealed 30 lesions in 15 (83%) patients. Uptake of both SSTR radioligands was found in several radioiodine-negative sites. No striking differences in lesion imaging by 111In-DOTA-LAN and 111In-DOTA-TOC were found. In both radioiodine-negative and radioiodine-positive patients, more lesions were SSTR-positive/18F-FDG-negative than were 18F-FDG-positive/SSTR-negative.
Adding a SSTR scan with these radioligands to the diagnostic work-up increases the diagnostic capacity in DTC, and should be considered particularly in radioiodine-negative patients with elevated thyroglobulin levels.
放射性碘阴性甲状腺癌在诊断和治疗上存在困难，因此需要实施新的成像和治疗策略。本研究有两个目的。其一，我们在体外研究了111铟-多胺大环配体-兰瑞肽（111In-DOTA-LAN）和111铟-多胺大环配体-D：苯丙氨酸1-酪氨酸3-奥曲肽（111In-DOTA-TOC）与分化型甲状腺癌（DTC）细胞的结合特性。其二，我们评估了与18F-氟脱氧葡萄糖（FDG）正电子发射断层扫描（PET）相比，使用这些放射性配体的生长抑素受体（SSTR）闪烁扫描对DTC患者肿瘤病灶的检测价值。
通过进行饱和及置换研究，在体外评估111In-DOTA-LAN和111In-DOTA-TOC与手术切除的甲状腺组织中分离出的细胞的结合情况。对18例甲状腺球蛋白升高的DTC患者（12例放射性碘阴性，6例放射性碘阳性）进行了111In-DOTA-LAN、111In-DOTA-TOC和18F-FDG PET扫描。
在所研究的细胞上发现了大量111In-DOTA-LAN和111In-DOTA-TOC的SSTR结合位点。两种SSTR放射性配体对这些SSTR结合位点均表现出高结合亲和力。111In-DOTA-LAN和111In-DOTA-TOC闪烁扫描分别在17例（94%）患者中检测到37个和33个病灶，而18F-FDG PET在15例（83%）患者中发现了30个病灶。在几个放射性碘阴性部位发现了两种SSTR放射性配体的摄取。未发现111In-DOTA-LAN和111In-DOTA-TOC在病灶成像方面有显著差异。在放射性碘阴性和放射性碘阳性患者中，SSTR阳性/18F-FDG阴性的病灶比18F-FDG阳性/SSTR阴性的病灶更多。
在诊断检查中增加使用这些放射性配体的SSTR扫描可提高DTC的诊断能力，对于甲状腺球蛋白水平升高的放射性碘阴性患者尤其应考虑使用。
