A Pilot Feasibility Study of Oral 5-Fluorocytosine and Genetically-Modified Neural Stem Cells Expressing E.Coli Cytosine Deaminase for Treatment of Recurrent High Grade Gliomas

Patient has had a prior, histologically-confirmed, diagnosis of a grade III or grade IV glioma (including glioblastoma, anaplastic astrocytoma, gliosarcoma, anaplastic oligodendroglioma, or anaplastic oligoastrocytoma), or has a prior, histologically-confirmed, diagnosis of a grade II glioma and now has radiographic findings consistent with a high-grade glioma (grade III or IV)

Imaging studies show evidence of recurrent supratentorial tumor(s)

The patient must be in need of a craniotomy for tumor resection or a stereotactic brain biopsy for the purpose of diagnosis or differentiating between tumor progression versus treatment-induced effects following radiation therapy +/- chemotherapy

Based on the neurosurgeon's judgment, there is no anticipated physical connection between the post-resection tumor cavity and the cerebral ventricles

Patient's high-grade glioma has recurred or progressed after chemoradiation

Patient has a Karnofsky Performance Status of \>= 70%

Patient has a life expectancy of \>=3 months

If patient requires corticosteroids for the control of cerebral edema, s/he must be on a stable dose for at least 1 week prior to enrollment

Patient has recovered from toxicity of prior therapies; an interval of at least 12 weeks must have elapsed since the completion of radiation therapy; at least 6 weeks since the completion of nitrosourea-containing chemotherapy regimen; and at least 4 weeks since the completion of a non-nitrosourea-containing cytotoxic chemotherapy regimen; if a patient's most recent treatment was with a targeted agent only; and s/he has recovered from any toxicity of this targeted agent, then a waiting period of only 2 weeks is needed from the last dose and the start of study treatment, with the exception of bevacizumab where a wash out period of at least 4 weeks is required before starting study treatment

Absolute neutrophil count of \>= 1,500 cells/mm\^3 and platelet count \>= 100,000 cells/mm\^3

Total bilirubin =\< 2.0 mg/dl

Aspartate aminotransferase (AST) (serum glutamic oxaloacetic transaminase \[SGOT\]) =\< 4 times the institutional upper limit of normal

Serum creatinine =\< the institutional upper limit of normal

Patients must be able to swallow pills

Patients must be able to understand and be willing to sign a written informed consent document

Female patients of child-bearing potential and sexually active male patients must agree to use an effective method of contraception while participating in this study

Women of childbearing potential must have a negative pregnancy =\< 2 weeks prior to registration

Patients must be tolerating oral intake

Patients' daily total dose of dexamethasone must be \< 12 mg by Day 4

What this study is about