Chin H W, Lefkowitz D M, Eisenberg R L
Department of Radiation Oncology Service, Overton Brooks Veterans Administration Medical Center, Shreveport, LA 71101.
Radiographics. 1992 Jul;12(4):721-9. doi: 10.1148/radiographics.12.4.1321981.
The extremely poor prognosis of high-grade brain tumors (glioblastoma multiforme and anaplastic astrocytomas) has been well documented in the literature. Almost 90% of patients die within 18 months after therapy, most commonly because of local persistence of the tumor, which may be controlled if a sufficient amount of irradiation can be delivered. Currently, postoperative radiation therapy offers the best median survival rate. However, the response to external-beam radiation therapy has reached a plateau because of the intolerance of healthy brain tissue to excessive irradiation. To treat these tumors, brachytherapy (interstitial implantation of radioactive sources) can be used with debulking surgery. This therapy is becoming an effective alternative to conventional external-beam radiation therapy, since it allows a higher dose to be delivered to the tumor bed without damaging the surrounding healthy brain tissue. With continual refinements of the technique, brachytherapy, performed by a skilled brachytherapy team, offers an opportunity to improve patient survival.
高级别脑肿瘤（多形性胶质母细胞瘤和间变性星形细胞瘤）的预后极差，这在文献中已有充分记载。几乎90%的患者在治疗后18个月内死亡，最常见的原因是肿瘤局部持续存在，如果能给予足够剂量的放疗，这种情况可能得到控制。目前，术后放射治疗的中位生存率最佳。然而，由于健康脑组织对过量放疗的耐受性，外照射放疗的疗效已达到平台期。为了治疗这些肿瘤，近距离放射治疗（放射性源的间质植入）可与肿瘤减量手术联合使用。这种治疗正成为传统外照射放疗的有效替代方法，因为它能在不损害周围健康脑组织的情况下，向肿瘤床给予更高剂量的放疗。随着技术的不断完善，由熟练的近距离放射治疗团队进行的近距离放射治疗为提高患者生存率提供了机会。
