PEDIATRIC LOW GRADE ASTROCYTOMA--TREATMENT GUIDANCE

描述：儿童低级别星形细胞瘤的临床转归 (LGA)是儿童中最常见的单一实体肿瘤类型， 变幻莫测。虽然完全切除通常是治愈的，但这不是 在许多情况下是可能的，因为LGA倾向于侵犯中线大脑 具有重要的系统生理学意义的结构。之后 部分切除，LGA可能保持稳定，可能继续生长，或可能 经历恶变。即使是轻微的术后生长也可以 会导致严重的神经缺陷或死亡。部分切除后， 生物学上有几个辅助管理选项可用 侵袭性肿瘤。分次放射治疗或化疗可能是 使用，但这些选项通常会尽可能地推迟，以避免 治疗导致的发育问题。立体定向放射治疗 可用于消融侵袭性肿瘤病灶(“修剪”)作为一种手段 控制体积增长，从而允许儿童发育到 可以考虑进行全球放射治疗或化疗的时间点。 传统的诊断神经成像方法无法识别 具有生物侵袭性的LGA，因此可以提供NOR辅助治疗 他们能确定肿瘤亚体积的位置吗？ “修剪”的攻击性特征。我们假设胆碱 从新发展的质子磁共振获得的信号测量 光谱成像(1H-MRSI)技术将克服这些缺点。 这一假说是基于研究表明，胆碱信号水平 是相关的增殖活动和我们自己的工作表明 组织病理学上均一的LGA病例表现为不同类型的 肿瘤胆碱信号。这一假设将通过以下方式进行检验 临床/实验室相关性研究和两项试点临床试验。在 临床/实验室相关性研究，术前测定 与代谢相关的1H-MRSI感兴趣区域之后将 确定了手术中切除的样本。我们将对这些进行分析 免疫细胞化学检测细胞增殖和凋亡特征。在……里面 临床先导试验，我们将寻求建立治疗后 胆碱测定可以预测未来的增长，1H-MRSI可能是 用于局部治疗的目标规划。

DESCRIPTION: Clinical outcome in cases of pediatric low grade astrocytoma (LGA), the single most common type of solid tumor in children, is unpredictable. Although complete resection is often curative, this is not possible, in many instances, because LGA tends to invade midline brain structures having essential systemic physiological significance. After partial resection, LGA may remain stable, may continue to grown, or may undergo malignant transformation. Even modest postoperative growth can result in severe neurological deficits or death. After partial resection, several adjunctive management options are available for biologically aggressive tumors. Fractionated radiation therapy or chemotherapy may be used, but these options are often deferred as long as possible to avoid therapy-attributable developmental problems. Stereotactic radiation therapy may be used to ablate aggressive tumor foci ("pruning") as a means of controlling volumetric growth thereby permitting the child to develop to the point where global radiation therapy or chemotherapy can be considered. Conventional diagnostic neuroimaging methods are unable to identify biologically aggressive LGA so that adjunctive therapy may be offered nor are they capable of identifying the location of tumor subvolumes exhibiting aggressive characteristics for "pruning". We hypothesize that choline signal measures obtained from newly developed proton magnetic resonance spectroscopic imaging (1H-MRSI) technology will overcome these shortcomings. The hypothesis is based on studies which suggest that choline signal levels are related proliferative activity and on our own work which has shown that histopathologically homogeneous LGA cases exhibit heterogeneous patterns of tumoral choline signal. The hypothesis will be tested with clinical/laboratory correlation study and two pilot clinical trials. In the clinical/laboratory correlation study, pre-operative determination of metabolically relevant regions of interest with 1H-MRSI will be followed by intra-surgical excision of samples identified. These will be analyzed immunocytochemically for proliferative and apoptosis characteristics. In the clinical pilot trials, we will seek to establish that post-therapy choline measures are predictive of future growth and that 1H-MRSI may be used in target planning for focal therapies.