OUTLINE: This is a dose-finding study. All patients receive stereotactically injected H5.010RSVTK (a recombinant adenovirus vector containing the herpes simplex virus thymidine kinase gene). Cohorts of 3-6 patients receive escalating doses of H5.010RSVTK until the maximum tolerated dose is reached. Ganciclovir is then given on the third post-injection day. Patients with unresectable tumors receive ganciclovir for 14 consecutive days. Patients with resectable tumors receive ganciclovir for 7 consecutive days before undergoing craniotomy with optimal debulking and injection of a second dose of the adenovirus vector followed by ganciclovir for 14 more days. Patients are followed monthly for survival.