Imahori Y, Ueda S, Ohmori Y, Sakae K, Kusuki T, Kobayashi T, Takagaki M, Ono K, Ido T, Fujii R
Department of Neurosurgery, Kyoto Prefectural University of Medicine, Japan.
Clin Cancer Res. 1998 Aug;4(8):1825-32.
Determination of tumor boron-10 (10B) levels is required for accurate neutron dosimetry during boron neutron capture therapy. We assessed a new method for quantitative measurement of boronated drug uptake in high-grade gliomas. This method uses positron emission tomography (PET) with fluorine-18-labeled L-fluoroborono-phenylalanine (L-18F-10B-FBPA), which was synthesized as an analogue of L-boronophenylalanine. We studied the accumulation of L-18F-10B-FBPA by PET in patients with high-grade gliomas. Dynamic PET studies of brain tumors revealed that L-18F-10B-FBPA accumulated gradually after bolus injection, and the value of PET activity divided by the integrated plasma activity reached a constant level 42 min after injection, which was defined as the incorporation constant (Ic*). This constant reflected the appropriate L-18F-10B-FBPA accumulation in tumor tissue. Based on the Ic* constant, the methods for estimating tumor 10B concentration were devised. With this method, the estimated values of 10B concentration in gliomas were very close to the 10B levels in surgical specimens. This method was based solely on PET and can potentially provide data that would assist in the selection of patients for future treatment with boron neutron capture therapy after surgical resection of their brain tumors.
在硼中子俘获治疗期间，为了进行精确的中子剂量测定，需要测定肿瘤硼 - 10（¹⁰B）水平。我们评估了一种定量测量高级别胶质瘤中硼化药物摄取的新方法。该方法使用正电子发射断层扫描（PET）和氟 - 18标记的L - 氟硼苯丙氨酸（L - ¹⁸F - ¹⁰B - FBPA），它是作为L - 硼苯丙氨酸的类似物合成的。我们通过PET研究了L - ¹⁸F - ¹⁰B - FBPA在高级别胶质瘤患者中的蓄积情况。对脑肿瘤的动态PET研究显示，静脉推注后L - ¹⁸F - ¹⁰B - FBPA逐渐蓄积，注射后42分钟PET活性值除以血浆活性积分达到恒定水平，该水平被定义为掺入常数（Ic*）。这个常数反映了L - ¹⁸F - ¹⁰B - FBPA在肿瘤组织中的适当蓄积。基于Ic*常数，设计了估计肿瘤¹⁰B浓度的方法。使用这种方法，胶质瘤中¹⁰B浓度的估计值与手术标本中的¹⁰B水平非常接近。该方法仅基于PET，有可能提供有助于选择在脑肿瘤手术切除后接受硼中子俘获治疗的患者的数据。
