A study of proliferative markers and tumor suppressor gene proteins in different grades of ependymomas.

Ependymomas are CNS tumors that originate from the spinal canal and walls of the ventricular system. Considerable controversy continues to exist with regard to their prognostic factors; age and extent of resection are the only statistically significant prognostic factors yet identified. The authors report a retrospective study of a homogenous population of 119 patients harbouring ependymomas between 1991 and 2002. All clinico-radiological and follow-up data were analyzed and a pathologic review was performed by two pathologists. Immunohistochemical staining for MIB-1, Topo IIalpha, p53 and MDM2 was performed. Histopathologic grades show relationship with MIB1 and Topo IIalpha labelling indices and cut-off values of 5% can differentiate between anaplastic and lower grades. p53 and MDM2 proteins expression are not common in ependymomas; however, they are seen in higher grades only and may be involved in the tumor progression.