From the Department of Neurology and Brain Tumor Center, Memorial Sloan-Kettering Cancer Center, NY, NY
Author's disclosure of potential conflicts of interest are found at the end of this article.
Address reprint requests to Andrew B. Lassman, MD, Department of Neurology and the Brain Tumor Center, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, NY, NY; e-mail: lassmana{at}mskcc.org
Overview: Anaplastic oligodendrogliomas (AOs) are uncommon primary brain tumors with greater sensitivity to therapy and better prognosis than high-grade astrocytomas. Maximal surgical resection improves outcome and improves diagnostic accuracy. Postoperative management is controversial. Radiotherapy (RT) is effective, but may be associated with neurocognitive toxicity, especially among long-term survivors. Remarkable responses to chemotherapy with procarbazine, lomustine, and vincristine (PCV) were anecdotally observed among patients with recurrent tumors. Small prospective trials confirmed that most anaplastic oligodendrogliomas respond to PCV. Therefore, two phase III randomized trials compared RT alone, against RT plus PCV for newly diagnosed anaplastic oligodendroglial tumors. Both trials confirmed that codeletion of chromosomes 1p and 19q predicted longer progression-free and overall survival regardless of therapy. Early results of these two trials demonstrated that combined therapy improved median progression-free survival, but not overall survival compared with RT alone at diagnosis, although most patients received chemotherapy at recurrence which affected overall survival results. Longer follow-up of 1p/19q co-deleted cases is ongoing. Small studies demonstrate that temozolomide is an effective chemotherapeutic that is less toxic than PCV, but its efficacy has not been formally compared against PCV. Prospective phase III trials will stratify patients by 1p/19q status and assess the benefit of temozolomide.
