====== Clinical Features ======

The classic presentation of ODG: a patient with [[seizure]]s for many years prior to the diagnosis which would be made when they later present with an apoplectic event due to peritumoral [[intracerebral hemorrhage]]. This scenario is less common with the proliferation of CT & MRI scans.

Seizures are the presenting symptoms in ≈ 50–80% of cases 
((Mork SJ, Lindegaard KF, Halvorsen TB, et al. Oligodendroglioma: Incidence and Biological Behavior in a Defined Population. J Neurosurg. 1985; 63:881–889))
((Chin HW, Hazel JJ, Kim TH, et al. Oligodendrogliomas. I. A Clinical Study of Cerebral Oligodendrogliomas. Cancer. 1980; 45:1458–1466))
with these slow-growing tumors present with seizures.

The remainder of presenting symptoms are nonspecific for ODG, and are more often related to local mass effect and less commonly to ↑ [[ICP]].