Predicting treatment response of malignant gliomas to bevacizumab and irinotecan by imaging proliferation with [18F] fluorothymidine positron emission tomography:: A pilot study
Predicting treatment response of malignant gliomas to bevacizumab and irinotecan by imaging proliferation with [18F] fluorothymidine positron emission tomography:: A pilot study
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DOI：
10.1200/jco.2006.10.5825
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发表时间：
2007-10-20
影响因子：
45.3
通讯作者：
Cloughesy, Timothy
中科院分区：
文献类型：
--
作者：
Chen, Wei;Delaloye, Sibylle;Cloughesy, Timothy
目的由于缺乏可靠的肿瘤反应预测指标，对恶性脑肿瘤的治疗效果评价具有挑战性。本研究探讨了使用[F-18]氟胸苷（FLT）（一种细胞增殖的成像生物标志物）的正电子发射断层扫描（PET）在接受贝伐单抗联合伊立替康治疗的复发性恶性胶质瘤患者中的预测价值。患者和方法接受双周贝伐单抗和伊立替康治疗的复发性恶性胶质瘤患者在基线、治疗后1 - 2周和治疗开始后6周进行FLT-PET前瞻性研究。根据标准摄取值测量，肿瘤FLT摄取减少25%以上被定义为代谢反应。将FLT反应与磁共振成像（MRI）显示的反应和患者生存期进行比较。结果纳入21例患者，其中19例可进行FLT-PET代谢反应评价。有9名应答者（47%）和10名无应答者（53%）。代谢应答者的生存时间是无应答者的3倍（10.8个月vs 3.4个月；P = 0.003），并且趋向于延长无进展生存期（P = 0.061）。与MRI反应（6周和最佳反应P = 0.060）相比，早期和晚期FLT-PET反应是总生存（1至2周，P = 0.006； 6周，P = 0.002）更重要的预测因子。结论FLT-PET作为影像学生物标志物可预测贝伐单抗和伊立替康治疗复发性胶质瘤患者的总生存率。在开始治疗后1 - 2周进行FLT-PET检查是否与研究表明的6周时一样具有预测性，值得进一步研究。
Purpose Evaluation of treatment effects in malignant brain tumors is challenging because of the lack of reliable response predictors of tumor response. This study examines the predictive value of positron emission tomography (PET) using [F-18] fluorothymidine (FLT), an imaging biomarker of cell proliferation, in patients with recurrent malignant gliomas treated with bevacizumab in combination with irinotecan.Patients and Methods Patients with recurrent malignant gliomas treated with biweekly cycles of bevacizumab and irinotecan were prospectively studied with FLT-PET at baseline, after 1 to 2 weeks, and after 6 weeks from start of treatment. A more than 25% reduction in tumor FLT uptake as measured by standardized uptake value was defined as a metabolic response. FLT responses were compared with response as shown by magnetic resonance imaging (MRI) and patient survival.Results Twenty-one patients were included, and 19 were assessable for metabolic response evaluation with FLT-PET. There were nine responders (47%) and 10 nonresponders (53%). Metabolic responders survived three times as long as nonresponders (10.8 v 3.4 months; P = .003), and tended to have a prolonged progression-free survival (P = .061). Both early and later FLT-PET responses were more significant predictors of overall survival (1 to 2 weeks, P = .006; 6 weeks, P = .002), compared with the MRI responses (P = .060 for both 6-week and best responses).Conclusion FLT-PET as an imaging biomarker seems to be predictive of overall survival in bevacizumab and irinotecan treatment of recurrent gliomas. Whether FLT-PET performed as early as 1 to 2 week after starting treatment is as predictive as the study indicates at 6 weeks warrants further investigation.