- For grade III malignant gliomas with 1p 19q codeletions: Standard front line therapy for newly diagnosed grade III malignant gliomas must include maximal feasible surgical resection (biopsy alone allowed), radiotherapy, and chemotherapy (PCV or temozolomide). If the patient did not receive any or all components of the standard front line therapy as detailed above for newly diagnosed grade III gliomas and the tumor then recurred or progressed, s/he must first receive at least one prior standard therapy or any appropriate combination of the components of standard therapy as detailed above and must experience further recurrence or progression before s/he is deemed eligible for this study. If the tumor was initially diagnosed as a grade II glioma with 1p 19q codeletions and now has recurred or progressed as a grade III tumor, it will be considered a secondary recurrent grade III glioma with 1p 19q codeletions and will be eligible for this study as long as prior treatment included maximal feasible surgical resection (biopsy alone allowed), radiotherapy, and chemotherapy (PCV or temozolomide).