Franzius Christiane, Hermann Klaudia, Weckesser Matthias, Kopka Klaus, Juergens Kai Uwe, Vormoor Josef, Schober Otmar
Department of Nuclear Medicine, University Hospital, Münster, Germany.
J Nucl Med. 2006 Oct;47(10):1635-42.
The 11C-labeled tracer meta-hydroxyephedrine (11C-HED) is a noradrenaline analog that was developed to visualize the sympathetic nervous system with PET. Initial clinical studies show a rapid uptake of 11C-HED in localized tumors of this system. Whole-body imaging with 11C-HED PET is now possible as PET/CT scanners allow a rather short examination time. The aim of this study was to evaluate the feasibility of whole-body 11C-HED PET/CT for examination of tumors of the sympathetic nervous system and to directly compare the results with 123I-labeled meta-iodobenzylguanidine (123I-MIBG) scintigraphy, including SPECT/CT.
In 19 consecutive patients, 9 mo to 68 y old (median, 32 y), 24 whole-body 11C-HED PET/CT (low-dose CT) examinations were performed. Scans were compared with attenuation-corrected 123I-MIBG SPECT/CT scans (24-h scan, low-dose CT). The intensity of tracer accumulation above background was visually analyzed in both scans, PET and SPECT, using a 4-value scale. In 11C-HED PET, mean and maximum standardized uptake values were determined for all lesions.
In 14 patients with 19 pairs of examinations, the following tumors were confirmed histologically: 6 neuroblastomas, 5 pheochromocytomas, 1 ganglioneuroblastoma, and 2 paragangliomas. In 5 patients, each having 1 pair of examinations, clinical follow-up and/or histologic examination did not reveal any tumor deriving from the sympathetic nervous system. 11C-HED PET/CT detected 80 of 81 totally depicted tumor lesions (sensitivity, 0.99; soft tissue, 61; bone, 19). 123I-MIBG SPECT/CT detected 75 of 81 lesions (sensitivity, 0.93; soft tissue, 56; bone, 19). With both methods, there were no false-positive lesions. The tumor-to-background contrast of 11C-HED uptake was higher in comparison with 123I-MIBG uptake in 26 lesions (0.32; soft tissue, 18; bone, 8), equal in 39 lesions (0.48; soft tissue, 30; bone, 9), and lower than 123I-MIBG uptake in 16 lesions (0.20; soft tissue, 14; bone, 2).
Whole-body imaging using 11C-HED PET/CT is feasible in the clinical setting of patients with tumors of the sympathetic nervous system. 11C-HED PET/CT detected more tumor lesions than 123I-MIBG SPECT/CT. However, tumor-to-background contrast of 11C-HED in lesions can be higher, equal, or lower compared with 123I-MIBG.
11C标记的示踪剂间羟基麻黄碱（11C-HED）是一种去甲肾上腺素类似物，开发用于通过PET可视化交感神经系统。初步临床研究表明，11C-HED在该系统的局部肿瘤中摄取迅速。由于PET/CT扫描仪允许较短的检查时间，现在可以进行11C-HED PET全身成像。本研究的目的是评估全身11C-HED PET/CT用于检查交感神经系统肿瘤的可行性，并将结果与123I标记的间碘苄胍（123I-MIBG）闪烁显像（包括SPECT/CT）直接比较。
对19例年龄9个月至68岁（中位数32岁）的连续患者进行了24次全身11C-HED PET/CT（低剂量CT）检查。将扫描结果与经衰减校正的123I-MIBG SPECT/CT扫描（24小时扫描，低剂量CT）进行比较。在PET和SPECT扫描中，使用4级量表对高于背景的示踪剂积聚强度进行视觉分析。在11C-HED PET中，测定所有病变的平均和最大标准化摄取值。
14例患者进行了19对检查，经组织学证实有以下肿瘤：6例神经母细胞瘤、5例嗜铬细胞瘤、1例神经节神经母细胞瘤和2例副神经节瘤。5例患者各进行了1对检查，临床随访和/或组织学检查未发现源自交感神经系统的任何肿瘤。11C-HED PET/CT在总共81个描绘的肿瘤病变中检测到80个（敏感性0.99；软组织61个；骨19个）。123I-MIBG SPECT/CT在81个病变中检测到75个（敏感性0.93；软组织56个；骨19个）。两种方法均未出现假阳性病变。与123I-MIBG摄取相比，11C-HED摄取的肿瘤与背景对比度在26个病变中更高（0.32；软组织18个；骨8个），在39个病变中相等（0.48；软组织30个；骨9个），在16个病变中低于123I-MIBG摄取（0.20；软组织14个；骨2个）。
在交感神经系统肿瘤患者的临床环境中，使用11C-HED PET/CT进行全身成像是可行的。11C-HED PET/CT检测到的肿瘤病变比123I-MIBG SPECT/CT更多。然而，与123I-MIBG相比，11C-HED在病变中的肿瘤与背景对比度可能更高、相等或更低。
