4TH VENTRICLE EPENDYMOMAS - A STUDY OF 20 CASES WITH SURVIVAL ANALYSIS

Twenty patients with fourth ventricle ependymoma were treated surgical ly at our Neurosurgery Division between January 1976 und December 1990 . Ependymoblastomas and mixed gliomas operated on in the same period h ave not been considered. A statistical analysis of our cases and a rev iew of the largest published series show that favourable prognostic fa ctors are: age over 16, post-operative radiotherapy to the posterior c ranial fossa and a good Karnofsky performance status (KPS) after opera tion. The 5-year survival rate of patients under 16 was 20%, in compar ison with 60% of adults (p = 0.013). Post-operative radiotherapy to th e posterior cranial fossa improved the survival markedly (5-year survi val rate 68%, versus 18% without treatment; p = 0.011). The difference s of survival are also significant according to a multivariate analysi s (p = 0.038). Patients with a post-operative KPS over 70 had a 5-year survival rate of 61% as against 17% of the group with a worse clinica l condition (p = 0.032); the multivariate analysis confirmed also that this difference was significant (p = 0.046). Pre-operative symptoms a nd signs, and KPS, histological grade and extent of surgical removal s eem to influence the prognosis, even if the differences of survival ar e not statistically significant. The statistical relevance of postoper ative residual tumour on CT or MRI was brought out on multivariate ana lysis (p = 0.044).