Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University, Baltimore, Maryland, USA.
Neuro Oncol. 2013 Mar;15(3):360-9. doi: 10.1093/neuonc/nos303. Epub 2013 Jan 14.
Neurocognitive toxicity from radiation therapy (RT) for brain tumors may be related to damage to neural progenitor cells that reside in the subventricular zone and hippocampus. This prospective study examines the relationship between RT dose to neural progenitor cell niches, temporal lobes, and cerebrum and neurocognitive dysfunction following cranial irradiation.
Standardized assessments of motor speed/dexterity, verbal memory, visual perception, vocabulary, and visuospatial working memory were conducted in 19 pediatric patients receiving cranial RT and 55 controls at baseline and 6, 15, and 27 months following completion of RT. Prescription doses ranged from 12 Gy to 59.4 Gy. Linear mixed effects regression model analyses were used to examine the relationships among neuropsychological performance, age, and radiation dose to the subventricular zone, hippocampus, temporal lobes, and cerebrum.
Performance on all neuropsychological tests, except vocabulary, was significantly reduced in patients relative to controls, particularly among younger children. Performance on motor speed/dexterity decreased with increasing dose to hippocampus (P < .05) and temporal lobes (P < .035). There was also a significant relationship between (i) reduced performance on verbal learning and increasing dose to the cerebrum (P = .022) and (ii) reduced performance on visual perception and increasing dose to the left temporal lobe (P = .038). There was no association between radiation dose to evaluated structures and performance on vocabulary or visuospatial working memory.
These prospective data demonstrate a significant association between increasing RT dose to hippocampus and temporal lobes and decline in neurocognitive skills following cranial irradiation. These findings have important implications for trials, including RTOG 0933 (hippocampal-sparing whole brain radiation therapy for brain metastases).
脑肿瘤放射治疗（RT）引起的神经认知毒性可能与位于侧脑室和海马的神经祖细胞损伤有关。本前瞻性研究探讨了颅照射后 RT 对神经祖细胞巢、颞叶和大脑的剂量与神经认知功能障碍之间的关系。
在接受颅 RT 的 19 例儿科患者和 55 例对照者中，在基线时以及 RT 完成后 6、15 和 27 个月时，进行了运动速度/灵巧性、言语记忆、视觉感知、词汇和视空间工作记忆的标准化评估。处方剂量范围为 12 Gy 至 59.4 Gy。线性混合效应回归模型分析用于研究神经心理学表现、年龄与侧脑室、海马、颞叶和大脑的放射剂量之间的关系。
与对照组相比，所有神经心理学测试（词汇除外）的患者表现均显著降低，尤其是年龄较小的儿童。运动速度/灵巧性随海马（P <.05）和颞叶（P <.035）剂量的增加而降低。言语学习能力下降与大脑剂量增加之间（P =.022）以及视觉感知能力下降与左侧颞叶剂量增加之间（P =.038）也存在显著关系。评估结构的放射剂量与词汇或视空间工作记忆的表现之间没有关联。
这些前瞻性数据表明，颅照射后海马和颞叶的 RT 剂量增加与神经认知技能下降之间存在显著关联。这些发现对试验具有重要意义，包括 RTOG 0933（脑转移瘤的海马保护全脑放疗）。
