Supratentorial ependymomas: Prognostic factors and outcome analysis in a retrospective series of 46 adult patients

BACKGROUND: Ependymomas account for 2% of all intracranial tumors in adults. Supratentorial ependymomas are less common than their infratentorial counterparts. To the authors' knowledge to date, the predictive values of surgery, histology, and patient-related prognostic factors for these tumors remain unresolved. The authors report a series of adult patients with supratentorial ependymomas to characterize the roles of surgery and histology in tumor control. METHODS: The authors retrospectively studied a homogenous population of 46 adult patients who had supratentorial ependymomas from 24 French neurosurgical centers between 1990 and 2004. All clinicoradiologic and follow-up data were analyzed, and a central pathologic review was performed by 2 certified neuropathologists. RESULTS: The mean (+/-standard error) 5- and 10-year overall survival rates for the entire population were 57.1% +/- 8.7% and 41.8% +/- 9.9%, respectively. The 5- and 10-year progression-free survival rates for the entire cohort were of 33.8% +/- 8.1% and 25.4 +/- 8%, respectively. On both univariate and multivariate analysis, age <55 years, greater extent of surgery, and lower histologic grade were associated with longer overall and progression-free survival. However, longer progression-free survival but was not considered a candidate variable for the multivariate model, because data were available for only 34 of 46 patients. CONCLUSIONS: In association with age and extent of surgery, histologic grade was identified as a major prognostic factor in adult supratentorial ependymomas. The application of a simple and reproducible grading scheme using objective anaplastic criteria appeared to be both useful practically and clinically applicable. The role of adjuvant radiotherapy for patients with incompletely resected, low-grade ependymomas needs to be investigated further.