The Prognostic Significance of Postoperative Residual Tumor in Ependymoma

Abstract

Between 1970 and 1989, 29 patients with intracranial ependymomas were evaluated and treated at the Children's Hospital in Boston. With a median follow-up of 82 months, the actuarial survival rates at 5 and 10 years were 61 ± 10% and 46 ± 12%, respectively. Anaplastic histological findings were uncommon (2 of 29). Initial postoperative radiotherapy was given to 25 patients, with a median tumor dose of 5360 cGy. With a median time to recurrence of 22 months, local failure (within 2 cm of original enhancing mass) was the predominant pattern of relapse (15 of 16 failures). The presence of radiographic residual disease seen on postoperative magnetic resonance imaging or computed tomographic scans was the most important prognostic variable for patients with intracranial ependymoma. Analysis of the 19 patients who underwent postoperative imaging revealed a 75 ± 15% 5-year freedom from progressive disease for 9 patients with no residual disease. as compared with 0% freedom from progressive disease for the 10 patients with gross residual disease (P = 0.03). In contrast, the surgical assessment of residual disease was not significant (P = 0.4). Age at presentation was also a significant prognostic factor. The overall actuarial survival rate at 12 years for infants 24 months or younger at diagnosis was 0%, as compared with 62 ± 13% for older patients (P = 0.03). For non-anaplastic ependymomas, complete surgical resection followed by local-field, high-dose (>54 Gy) radiotherapy appears to offer the greatest chance for long-term survival. Because of the markedly reduced survival rate for patients with radiologically apparent postoperative disease, maximal surgical resection and novel therapeutic endeavors appear warranted for this high-risk group. Future protocols should use postoperative imaging, not operative reports, to stratify patients with ependymoma.

A multicenter study of the prognosis and treatment of adult brain ependymal tumors

“…5,9,12,18,19,34 For this analysis, confounding factors included the unreliability of surgical assessment of the degree of ablation 35 and differences in the composition of compared groups with respect to age, performance status, and tumor grade, site, and size. In the current series, as in previous studies, 15,16 no statistically significant difference in overall survival was observed on univariate or multivariate analysis.…”

“…18 Nonetheless, the role of RT in treating Grade 2 ependymoma is controversial. In fact, the impact of RT on survival is not clearly supported by consistent statistical data, as no randomized trial has been conducted and retrospective studies have been uncontrolled or involved comparisons with historical controls, 20,29,35 while data on survival after surgery alone are severely limited in modern series.…”

“…Recently, a number of smaller series have reported positive outcomes in children 20,27,28,[35][36][37][38][39][40] or adults 15 with totally resected Grade 2 intracranial ependymoma who did not receive RT after surgery. Reserving RT for recurrent disease appears to be an attractive strategy for patients with Grade 2 ependymoma, provided that the behavior of this malignancy is similar to that of lowgrade glioma, in which no detrimental impact on OS was observed when a 'wait and see' policy was followed after surgery.…”

Genetic abnormalities detected in ependymomas by comparative genomic hybridisation

“…Various factors have been reported to influence prognosis, though clinical research in this area has produced many conflicting results. However, gross surgical resection and the use of radiotherapy have been consistently associated with enhanced event-free and overall survival (Nazar et al, 1990;Sutton et al, 1990;Healey et al, 1991;Vanuytsel et al, 1992;Ferrante et al, 1994;Pollack et al, 1995;Bouffet et al, 1998;Robertson et al, 1998;Horn et al, 1999;Grill et al, 2001). Histological features of anaplasia, such as mitoses, microvascular proliferation and necrosis, serve as indicators of biological behaviour in other gliomas, including diffuse astrocytic tumours and oligodendrogliomas (Cohadon et al, 1985;Burger and Green, 1987;Ellison, 1998).…”

Anaplastic ependymoma of the fourth ventricle causing obstrictive hydrocephalus

“…About fifty percent (50%) occur before five years of age. Two-thirds of ependymomas are located infratentorially 2,3,4,5,6 . The optimal management of fourth ventricular ependymomas remains controversial 7 .…”