目的:胶质母细胞瘤的O-(2-[18F]-氟乙基)-L-酪氨酸(FET)PET试验是澳大利亚前瞻性的,多中心研究评估FETPET用于胶质母细胞瘤患者管理。FETPET成像时间点是放化疗前(FET1),放化疗后1个月(FET2),和可疑进展(FET3)。在招募参与者之前,现场核医学医师(NMP)接受了FETPET轮廓和图像解释的认证。
方法:在基准病例(n=6)评估生物肿瘤体积(BTV)轮廓(3×FET1)和图像解释(3×FET3)上,需要通过≥2NMPs来完成轮廓和动态分析。专家审查了数据,并指出了违规行为。BTV定义包括肿瘤背景比(TBR)阈值为1.6,在对侧正常脑中具有新月形背景轮廓。复发/假性进展解释(FET3)需要评估最大TBR(TBRmax),动态分析(时间活动曲线[TAC]型,到达峰值的时间),和定性评估。组内相关系数(ICC)评估体积协议,变异系数(CoV)比较不同病例的最大/平均TBR(TBRmax/TBRmean),和成对分析评估空间(骰子相似系数[DSC])和边界一致性(豪斯多夫距离[HD],平均绝对表面距离[MASD])。
结果:数据来自21个NMP(10个中心,各n≥2个),20个接受了审查。最初的通过率为93/119(78.2%),并且完成了27/30要求的重新提交。在FET1的25/72(34.7%;13/12次/大)和FET3的22/74(29.7%;14/8次/大)报告中发现了违规行为。重新提交的主要原因如下:BTV过度轮廓(15/30,50.0%),背景放置(8/30,26.7%),TAC分类(9/30,30.0%),和图像解释(7/30,23.3%)。BTV的CoV中位数和范围,TBRmax,TBRmean为21.53%(12.00-30.10%),5.89%(5.01-6.68%),和5.01%(3.37-6.34%),分别。BTV一致性中等至优秀(ICC=0.82;95%CI,0.63-0.97),具有良好的空间(DSC=0.84±0.09)和边界(HD=15.78±8.30mm;MASD=1.47±1.36mm)一致性。
结论:FIG研究认证计划增加了研究地点的专业知识。TBRmax和TBRmean是稳健的,观察到的BTV描绘和图像解释具有相当大的可变性。
The O-(2-[18F]-fluoroethyl)-L-tyrosine (FET) PET in Glioblastoma (FIG)
trial is an Australian prospective, multi-centre
study evaluating FET PET for glioblastoma patient management. FET PET imaging timepoints are pre-chemoradiotherapy (FET1), 1-month post-chemoradiotherapy (FET2), and at suspected progression (FET3). Before participant recruitment, site nuclear medicine physicians (NMPs) underwent credentialing of FET PET delineation and image interpretation.
Sites were required to complete contouring and dynamic analysis by ≥ 2 NMPs on benchmarking cases (n = 6) assessing biological tumour volume (BTV) delineation (3 × FET1) and image interpretation (3 × FET3). Data was reviewed by experts and violations noted. BTV definition includes tumour-to-background ratio (TBR) threshold of 1.6 with crescent-shaped background contour in the contralateral normal brain. Recurrence/pseudoprogression interpretation (FET3) required assessment of maximum TBR (TBRmax), dynamic analysis (time activity curve [TAC] type, time to peak), and qualitative assessment. Intraclass correlation coefficient (ICC) assessed volume agreement, coefficient of variation (CoV) compared maximum/mean TBR (TBRmax/TBRmean) across cases, and pairwise analysis assessed spatial (Dice similarity coefficient [DSC]) and boundary agreement (Hausdorff distance [HD], mean absolute surface distance [MASD]).
Data was accrued from 21 NMPs (10 centres, n ≥ 2 each) and 20 underwent review. The initial pass rate was 93/119 (78.2%) and 27/30 requested resubmissions were completed. Violations were found in 25/72 (34.7%; 13/12 minor/major) of FET1 and 22/74 (29.7%; 14/8 minor/major) of FET3 reports. The primary reasons for resubmission were as follows: BTV over-contour (15/30, 50.0%), background placement (8/30, 26.7%), TAC classification (9/30, 30.0%), and image interpretation (7/30, 23.3%). CoV median and range for BTV, TBRmax, and TBRmean were 21.53% (12.00-30.10%), 5.89% (5.01-6.68%), and 5.01% (3.37-6.34%), respectively. BTV agreement was moderate to excellent (ICC = 0.82; 95% CI, 0.63-0.97) with good spatial (DSC = 0.84 ± 0.09) and boundary (HD = 15.78 ± 8.30 mm; MASD = 1.47 ± 1.36 mm) agreement.
The FIG
study credentialing program has increased expertise across
study sites. TBRmax and TBRmean were robust, with considerable variability in BTV delineation and image interpretation observed.