Basic and clinical research for managemennt of brain tumor

脑肿瘤的治疗是通过手术、放射治疗、化疗和生物反应调节剂等多种治疗手段的综合治疗。我们研究了脑肿瘤的生物学和组织学特点，尝试了局部放射治疗脑肿瘤的新方法。在我们的临床中，聚焦到颅内病变的辐射是由两个不同的系统提供的，一个是准直的钴-60源(伽玛刀)，另一个是新的间质放射源(软X射线)。光子放射外科系统(PRS)设备是一种轻便、手持、由电池供电的光子发生器。探头顶端直径3 mm，长10 cm。产生的X射线能量随着距离探测器的距离而急剧下降，有可能一次有效地照射直径达3.0厘米的病变。该系统可以在没有任何特殊辐射防护屏蔽的情况下在手术室或病房中使用。我们对45例脑部病变患者进行了立体定向活检术和肿瘤部分切除术后单纯间质内放射治疗。每分钟200cGy射线的剂量是可能的，允许在不到20分钟内对直径3厘米的病变进行15Gy射线照射。所有患者对手术的耐受性良好。手术和放疗后均未发现神经功能缺陷。目前，该疗法的临床疗效仍在研究中，但前景看好。

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.