Bevacizumab and Carmustine in Treating Patients With Relapsed or Progressive High-Grade Glioma

RATIONALE: Monoclonal antibodies, such as bevacizumab, can block tumor growth in different ways. Some block the ability of tumor cells to grow and spread. Others find tumor cells and help kill them or carry tumor-killing substances to them. Bevacizumab may also stop the growth of tumor cells by blocking blood flow to the tumor. Drugs used in chemotherapy, such as carmustine, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Giving bevacizumab together with carmustine may kill more tumor cells. PURPOSE: This phase II trial is studying how well giving bevacizumab together with carmustine works in treating patients with relapsed or progressive high-grade glioma.