Basic and clinical research for managemennt of brain tumor

脑肿瘤的治疗是通过多模式治疗，包括手术、放疗、化疗和生物反应调节剂的细胞生产。我们研究了脑肿瘤的生物学和组织学特点，并尝试了局部放射治疗脑肿瘤的新方法。在我们的中国，对颅内病变的聚焦辐射由两个不同的系统提供，一个准直钴60源（伽玛刀）和一个新的间质辐射源（软x射线）。光子放射外科系统（PRS）装置是一种轻量级、手持式、电池供电的光子发生器。探针的尖端直径为3mm，长度为10cm。所产生的x射线能量随着与探针的距离而急剧下降，具有一次有效照射直径达3.0cm的病变的潜力。该系统可在手术室或病房中使用，无需任何特殊的辐射防护屏蔽[61]。我们治疗了45例脑病变患者，其中包括手术后的立体活检和部分切除肿瘤。每分钟200 cGy的剂量是可能的，允许在不到20分钟的时间内对直径3厘米的病变施用15 Gy。所有患者对手术的耐受性都很好。手术和放疗后无神经功能缺损。PRS的临床疗效目前正在调查中，但它似乎很有希望。

The treatment of brain tumor is that of cytpreduction through multimodality therapy, including surgery, radiation therapy, chemotherapy and biolgical response modifier.We studied the biological and histological characteristics of brain tumors and tried the new managements of brain tumor using local radiotherapeutic methods. In our chinic, focused radiation to the intracranial lesion is delivered by two different systems, a collimated cobalt-60 source (gammaknife) and a new interstitial radiation source (soft X-rays). The photon radiosurgery system (PRS) device is a lightweight, handheld, battery-powered photon generator. The tip of the probe is 3 mm in diameter and 10cm in length. The energy of X-rays generated decreases sharply with distance from the probe, carrying the potential to effectively irradiate a lesion as large as 3.0cm in diameter at a time. This system can be used without any special radioprotective shielding in an operating theater or a ward [61. We treated 45 patieats with cerebral lesions with a single fraction of interstitial irradiation by PRS after surgery including stereotatic biopsy and partial removal of the tumor. Doserates of 200 cGy per minute are possible, allowing for the administration of 15 Gy to a lesion 3 cm in diameter in less than 20 min. All patients tolerated the procedure weii. No neurological deficits were noted after surgery and irradiation. The clinical efficacy of PRS is now under investigation, but it appears quite promising.