Combined treatment of fourth ventricle ependymomas: Report of 26 cases

BACKGROUND This study investigated the relevance of prognostic factors and the impact of histological features in posterior fossa ependymoma. METHODS The charts of 26 patients (aged 1-59 years, mean 20.6 years; 11 adu lts) with posterior fossa ependymoma operated on between January 1983 and D ecember 1994 were reviewed and patients followed up (mean: 93 months). RESULTS Gross total resection was performed in 18 patients (69%), subtotal in seven patients (27%), biopsy in one patient (4%). One patient (3.8%) dev eloped respiratory complications and died. All patients underwent posterior fossa radiotherapy (5000 cGy) after surgery. Four children first received chemotherapy and then radiotherapy only when at least 3 years old. Eleven p atients (42%) received radiotherapy and subsequently chemotherapy. The 5-ye ar survival rate was 90% for adults and 40% for children (less than or equa l to 6 years). CONCLUSIONS This review suggests that a) younger patients (less than or equ al to 6 years), despite multimodality treatment, have a poor prognosis; b) the microanatomical location of the tumor (lateral recess, roof, and floor) influences the extent of tumor removal (p < 0.05); c) longer survivals are associated with complete removal (p < 0.05); d) the histological feature m ost often related to a poor prognosis is a high mitotic index (p < 0.05), w hereas vascular proliferation (p = 0.149), necrosis (p = 0.215), nuclear at ypia (p = 0.384) and high cellularity (p = 0.786) do not affect survival; e ) histological classification (WHO) does not reflect different survival rat es between ependymomas and anaplastic ependymomas (p = 0.082). (C) 2000 by Elsevier Science Inc.