Habrand J L, Benk V, Bouhnik H, Teissier E, Kalifa C, Sarrazin D
Département des radiations, Institut Gustave-Roussy, Villejuif, France.
Bull Cancer. 1990;77(7):725-36.
Radiotherapy still represents with surgery the cornerstone in the management of pediatric brain tumors. Techniques of irradiation have benefited greatly from modern imaging, CT scan and MRI for tumor-volume delineation, as well as megavoltage equipment, mainly linear accelerators delivering both high-energy X-Rays and electrons, widely used in cranial-spinal irradiations. Furthermore, new modalities of doses and volumes have been tested in various tumors (medulloblastomas, germ cell tumors...), in studies frequently combining chemotherapy with conventional therapies. Nevertheless, local control remains a major concern in tumors such as brain stem and high grade supratentorial gliomas. Concerning iatrogenic neurological sequelae, particularly harmful in children, limited data suggest an improvement in recent years. This improvement is partly due to the reduced prophylactic doses for the treatment of medulloblastomas, but further long-term observations are necessary. For these reasons, multiple technical innovations have been investigated. Some of them concern irradiation selectivity: stereotactic pencil beams, interstitial brachytherapy, heavy charged particles, 3-dimensional treatment planning. Others aim to increase the irradiation "efficacy": multifractionation, high LET particles, radiation-sensitizers.
放射治疗与手术仍然是小儿脑肿瘤治疗的基石。现代成像技术（CT扫描和MRI用于肿瘤体积勾画）以及兆伏级设备（主要是能产生高能X射线和电子的直线加速器，广泛用于颅脊髓照射）使放射治疗技术受益匪浅。此外，在各种肿瘤（髓母细胞瘤、生殖细胞肿瘤等）中已经对新的剂量和体积模式进行了测试，这些研究经常将化疗与传统疗法相结合。然而，对于脑干肿瘤和幕上高级别胶质瘤等肿瘤，局部控制仍然是一个主要问题。关于医源性神经后遗症，这对儿童尤其有害，有限的数据表明近年来有所改善。这种改善部分归因于髓母细胞瘤治疗中预防性剂量的减少，但仍需要进一步的长期观察。出于这些原因，人们研究了多种技术创新。其中一些涉及照射的选择性：立体定向笔形束、组织间近距离治疗、重带电粒子、三维治疗计划。其他的旨在提高照射“效果”：多分次照射、高传能线密度粒子、放射增敏剂。
