Yamada Y, Uchida Y, Tatsumi K, Yamaguchi T, Kimura H, Kitahara H, Kuriyama T
Department of Chest Medicine, School of Medicine, Chiba University, Japan.
J Nucl Med. 1998 Jul;39(7):1160-6.
Uptake of 18F-fluorodeoxyglucose (FDG) and 11C-methionine (Met) in mediastinum and hilar lymph nodes was studied using PET in 31 patients with sarcoidosis. The aim of our study was to examine whether these different tracers play a differential role in clinical assessment of pulmonary involvement.
Fluorine-18-fluorodeoxyglucose and 11C-Met PET were administered on different days. The differential absorption ratio of these tracers was calculated for the region of interest with the highest level of activity. Clinical reassessment of sarcoidosis was made at least 1 yr after the first PET examination. In seven patients whose lymph nodes still remained visible by other imagings at the time of reevaluation, the same PET study was performed again.
Both FDG and Met were accumulated in the lymph nodes in all but one patient. The FDG and Met uptake ratios in all patients were not correlated, but they could be divided into the FDG-dominant group (FDG/Met uptake ratio > or = 2) and the Met-dominant group (FDG/Met uptake ratio < 2). Within each group, the FDG and Met uptake values were correlated. The rate of improvement assessed by clinical status and chest radiographs was considerably higher in the FDG- (78%) than in the Met-dominant group (33%). In the seven patients of the repeated PET examination, their FDG/Met uptake ratios were generally unchanged after 1 yr.
The results suggest that the FDG/Met uptake ratio using PET may reflect the differential granulomatous status in sarcoidosis and be a useful tool for pretreatment evaluation.
采用正电子发射断层扫描（PET）对31例结节病患者纵隔及肺门淋巴结摄取18F-氟脱氧葡萄糖（FDG）和11C-蛋氨酸（Met）的情况进行了研究。本研究的目的是探讨这些不同的示踪剂在肺部受累临床评估中是否发挥不同作用。
在不同日期分别给予氟-18-氟脱氧葡萄糖和11C-Met PET检查。计算活性水平最高的感兴趣区域内这些示踪剂的差异摄取率。在首次PET检查后至少1年对结节病进行临床重新评估。在重新评估时，7例患者的淋巴结通过其他影像学检查仍可见，再次进行相同的PET研究。
除1例患者外，所有患者的淋巴结均有FDG和Met积聚。所有患者的FDG和Met摄取率无相关性，但可分为FDG优势组（FDG/Met摄取率≥2）和Met优势组（FDG/Met摄取率<2）。在每组中，FDG和Met摄取值具有相关性。FDG优势组（78%）通过临床状况和胸部X线片评估的改善率显著高于Met优势组（33%）。在重复进行PET检查的7例患者中，1年后其FDG/Met摄取率总体未变。
结果表明，PET检查使用的FDG/Met摄取率可能反映结节病中不同的肉芽肿状态，是预处理评估的有用工具。
