Interstitial irradiation with stereotactically implanted I-125 seeds for the treatment of cerebral glioma

Abstract Owing to its low rate of side effects and its high efficacy, interstitial irradiation with low-activity seeds should be the first therapeutic step in small (maximal diameter 40 mm), well-circumscribed, lowgrade gliomas affecting the brain stem, other midline structures, or eloquent cerebral areas. In anaplastic gliomas, a therapeutic schedule using low-activity seeds and combining interstitial irradiation with radiotherapy (reduced boost dose of 1530 Gy) seems to be more effective than interstitial irradiation alone. Compared with interstitial irradiation with high-activity seeds, this combined irradiation schedule caused no space-occupying radiation necrosis. Thus, it can be recommended as up-front treatment in patients with small (maximal diameter <40 mm) inoperable anaplastic gliomas. The use of high-activity I-125 seeds and interstitial irradiation at comparably high dose rates, integrating a small penumbra of normal brain tissue into the treatment volume, improved survival significantly in patients with primary highly malignant gliomas. In patients with recurrent tumors, the same treatment schedule did not substantially prolong survival compared with results obtained after resection plus radiotherapy. Owing to the high frequency of space-occupying radiation necrosis (40-60%), this schedule is only applicable in surgically accessible tumors. The application of lowactivity I-125 seeds (in primary glioblastomas in combination with radiotherap...
Source: Critical Reviews in Neurosurgery - Category: Neurosurgery Source Type: research