Subependymoma (WHO grade I tumor) is a slow-growing glial neoplasm that is typically attached to the ventricular wall (Wiestler et al. 2000c).
In a large series of cases, this histologic type accounted for 8.3% of ependymal tumors. It is an unusual highly differentiated neoplasm that is considered a variant distinct from ependymoma. This tumor occurs most frequently in middle-aged and elderly males and is rarely found in children.
Imaging and Location
A typical imaging finding in subependymoma is its location as an intraventricular lesion (Hoeffel et al. 1995).
Differentiation from ependymomas is difficult especially in large tumors, which tend to be as heterogeneous as described above. Small masses, however, are homogeneously hyperintense on T2-weigthed images.
Enhancement is uncommon and can be used for differentiation from other pathologies with intraventricular manifestation.
Treatment and prognosis
Subependymoma carries a good prognosis; surgical removal is usually curative.
- M.F. Reiser, W. Semmler, H. Hricak (Eds.) "Magnetic Resonance Tomography", Springer 2008