Recurrent malignant glioma in adults

Stephen B. Tatter

Meaningful palliation is possible for selected patients with recurrent malignant glioma (glioblastoma multiforme, anaplastic astrocytoma, anaplastic oligodendroglioma, or anaplastic mixed oligoastrocytoma) using aggressive treatment. Although long-term disease-free survival occurs in fewer than 10% of patients, most who achieve such survival have been treated for multiple recurrences. Surgical resection with the placement of lomustine-releasing wafers is the only therapy proven in randomized trials to be beneficial for recurrent malignant gliomas. Reoperation is indicated when local mass effect limits the quality of life. Reoperation may make other treatments more effective by removing treatment-resistant hypoxic cells and thereby prolonging high-quality survival. Combination chemotherapy (including procarbazine and a nitrosourea) provides dramatic benefit for many recurrent anaplastic or aggressively behaving oligodendrogliomas and anaplastic mixed oligoastrocytomas. For other recurrent malignant gliomas, single-agent cytotoxic chemotherapy (eg, intravenous lomustine or platinums, oral carmustine, temozolomide, or procarbazine) appears to provide equivalent results and better quality of life at a lower cost than do the combinations of cytotoxic drugs. A randomized phase II trial demonstrates that temozolomide provides longer progression-free survival and better quality of life than standard-dose procarbazine in patients with recurrent glioblastoma multiforme. Because benefits of available cytotoxic chemotherapy for anaplastic astrocytoma and glioblastoma are small, participation in clinical trials is appropriate for most patients. Reirradiation (using stereotactic or three-dimensional conformal techniques with or without concomitant cytotoxic chemotherapy) as radiation sensitization can prolong high-quality survival in selected patients. Specific examples include radiosurgery with the gamma knife or with linear accelerators, intracavitary radiation with the newly US Food and Drug Administration-approved GliaSite (Proxima Therapeutics, Alpharetta, GA) radiation therapy system, low dose rate permanent-seed brachytherapy, and high dose rate stereotactic brachytherapy. Dexamethasone (used for the shortest time in the lowest effective doses) can provide symptomatic benefits. Osmotic diuretics such as mannitol reduce cytotoxic edema more rapidly.