Meningiomas are among the most common brain tumors in adults. They are most 
commonly located over the cerebral convexities and are infrequently found in an 
intraventricular location. Ionizing cranial radiation is a risk factor for late 
occurrence of meningiomas within the radiation field. While pathologic grading 
of meningiomas is straightforward, significant variability often exists between 
pathologists in applying standard grading criteria. This has implications for 
prognosis. Radiation-induced meningiomas may also have predilection to recur. 
The authors describe a case of an intraventricular meningioma occurring 23 years 
after cranial irradiation for childhood acute lymphoblastic leukemia.