低级别脑胶质瘤放射治疗进展

Progress of radiotherapy for low-grade glioma

脑胶质瘤是常见的原发性中枢神经系统肿瘤之一,占脑恶性肿瘤的80.8%,低级别胶质瘤(LGG)约占脑胶质瘤的15%。大部分LGG最终会转化为预后差的高级别胶质瘤。放射治疗是LGG的有效治疗方式之一,尤其对不适宜手术的患者更为重要。放疗可杀灭肿瘤细胞,同时可延缓LGG恶性转化,改善患者生存率。近年来,LGG分子生物学方面的研究取得了较大进展,分子研究已经证实了LGG的遗传和生物学异质性,越来越多的研究倾向基于分子亚型的放疗。新的影像技术特别是多模态影像技术提高了LGG原发肿瘤和术后残留病灶的识别能力以及放疗后肿瘤进展和假性进展的鉴别能力,为靶区勾画和治疗方案选择提供可靠依据。质子放疗、近距离放疗和磁共振引导放疗等放疗新技术的发展进一步增加了LGG放疗的精度和疗效。随着分子研究水平的不断深入以及影像与放疗技术的不断发展,LGG放疗中病情评估、放疗时机确定、靶区勾画、剂量处方、放疗技术选择和放疗疗效评估等均有了快速进展,本研究对此进行综述,为LGG精准放疗的开展与实施提供依据。

Gliomas are the most common primary central nervous system tumor,accounting for 80.8%of brain malignancies,and low-grade gliomas account for about 15%of gliomas.A significant number of low-grade gliomas can ultimately convert to fatal high-grade gliomas,with worse prognosis.Radiotherapy is one of the effective therapeutical forms for low-grade gliomas,especially for patients who are not suitable for surgery.Radiotherapy have a cytocidal effect on tumor,and delay the malignant transformation of low-grade gliomas,which improve the survival of patients.In the past decade,unprecedented advances have been made in the molecular biology of low-grade gliomas.Molecular research has confirmed that low-grade gliomas are genetically and biologically heterogeneous.More and more studies tend to study radiotherapy based on molecular subtypes.Novel medical imaging technologies,especially multimodal imaging technologies,can improve the ability of identifying primary tumors and residual lesions for low-grade gliomas,as well as the ability to discriminate progression and pseudo progress after radiotherapy,so as to provide a reliable foundation for target delineation and treatment scheme selection.The development of radiotherapy technologies such as proton radiotherapy,brachytherapy and magnetic resonance guided radiotherapy further increase the accuracy and efficacy of radiotherapy for low-grade gliomas.With advancement of molecular research and the continuous development of medical imaging and radiation therapy technologies,the links of condition evaluation,determination of radiotherapy time,target delineation,dose prescription,selection of radiation technologies and evaluation of radiotherapy efficacy in radiotherapy of low-grade gliomas have developed rapidly.In this article,we review these advances,which could be useful for the development and implementation of precision radiotherapy for low-grade gliomas.