Gliomas with 1p/19q codeletion: a.k.a. oligodendroglioma.

Today, treatment recommendations for patients with all types of gliomas are based on light microscopic evaluation of tumor tissue with no allowance for genetic variability. Oligodendrogliomas are treated in a uniform manner with, as yet, no unique therapeutic approach or targeted therapy for those harboring a codeletion of chromosomes 1p and 19q. Surgical resection and radiotherapy are the standards-of-care for patients with oligodendrogliomas. Surgery improves symptoms, especially headache or seizures, and radiotherapy controls tumor growth for most patients. By extrapolation from randomized trials of glioblastoma, radiotherapy likely prolongs survival. Uncertainties persist about the timing of radiotherapy in the management of patients with low-grade oligodendrogliomas, but a superior antitumor treatment has yet to emerge. That said, the recognition that oligodendrogliomas with 1p/19q loss are sensitive to current therapies and slowly growing is already influencing our management of patients with this type of glioma, spawning trials in which patients are selected by molecular signature.