Extraventricular cerebral anaplastic ependymomas.
BACKGROUND: Anaplastic ependymomas are considered to be uncommon cerebral tumors by most authors. We have had the opportunity to study 34 cases of such lesions in 13 years. METHODS: 34 cases of anaplastic ependymoma operated in different hospitals of Maracaibo, Venezuela, during the period of 1983-1995 were analyzed. Cases of ependymoblastoma were excluded. RESULTS: Adult patients made up most of the present series. All patients harbored supratentorial growths in locations distant from the ventricular system. The microscopic pattern was of limited value to establish prognosis, for there was no constant correlation between the histologic features and tumor relapse; only in sporadic cases in which high cell density and conspicuous mitotic activity were maximally expressed, did tumor relapse occur shortly after removal of the lesion. CONCLUSION: This type of paradoxical behavior being the rule makes all attempts at predicting prognosis in these entities a disappointing task.