Boost Gamma Knife radiosurgery in the treatment of primary glial tumors.

By sheer weight of numbers, patients with malignant glial neoplasms of the astrocytoma series (glioblastoma multiforme, anaplastic astrocytoma, astrocytoma grade 3 or grade 4, depending upon the grading system), and to a lesser extent, patients with high-grade ependymomas, oligodendrogliomas or other primary brain tumors, have represented a significant proportion of individuals referred for consideration of radiosurgery. Although most such tumors are either too large, too poorly defined on imaging studies, or too infiltrative to consider for treatment, hundreds of highly selected patients with smaller, apparently well-circumscribed tumors have been treated using radiosurgery over the past few years. To better define the role of radiosurgery in the treatment of patients with malignant primary brain tumors, the first 30-month experience with the 60Co Gamma Unit at the Mayo Clinic was reviewed.