Intracranial ependymomas in adult patients: analyses of prognostic factors

The goal of our study is to identify significant prognostic factors for a series of intracranial ependymomas in an adult population. Age, location, histology, preoperative clinical status, extent of resection and radiotherapy were examined. Our series includes 34 patients. Ten tumors were located in the brain parenchyma, 5 in the lateral ventricle, 8 in the third and 11 in the fourth ventricle. Seventeen ependymomas were grades 2 and 17 were anaplastic. Surgical resection was gross-total in 27 patients and partial in 7. At a mean follow-up of 9 years (+/- 1 year) 16 patients died and, among the 18 survivors 14 are in complete remission and 4 present a local recurrence. The 5- and 10-year overall survival rates were respectively 62% and 43%. The 5- and 10-year progression-free survivals were 47% and 43%. Univariate analysis revealed that location in the brain parenchyma and anaplasia are the only statistically significant predictors of poor outcome. We can make out three groups of patients from our series: the first encompasses patients operated on for an intraparenchymal tumor, in all our cases an anaplastic ependymoma, with a 5-year rate of tumor-related deaths of 100%. The second group includes fourth ventricle ependymomas, which are mostly grade 2 tumors. They display a 10-year survival rate of 90%. Last group entails lateral and third ventricle ependymomas, of both low and high grade, with a 10-year survival rate of 60% for lateral ventricle and 35% for third ventricle tumors.