INTRACRANIAL EPENDYMOMAS - ANALYSIS OF PROGNOSTIC FACTORS IN A POPULATION-BASED SERIES

A retrospective study of 31 children presenting in the period 1976-199 3 with intracranial ependymomas in the south-west region of the UK was performed. The diagnosis was confirmed by histological review and sev eral histological variables recorded, including pleomorphism, cellular ity, numbers of mitotic figures and extent of necrosis. Histological f eatures, presentation and treatment were correlated with outcome. Elev en patients had supratentorial primaries and 20 infratentorial primari es. Seven patients had macroscopically complete resections of which 5 had supratentorial primaries. Eight patients had no other therapy apar t from surgery. Six patients received craniospinal irradiation, 11 had involved-field irradiation and 14 did not have radical radiotherapy. Twelve patients received chemotherapy. Eleven patients are relapse-fre e at a median of 43 months. Of the 20 relapses, 19 were local and only 1 metastatic. The grade of the tumor assigned at presentation had no correlation with outcome. On histological review, the only feature tha t had a significant correlation (p = 0.05) with survival was tumor cel lularity. There was a survival advantage for a supratentorial primary site (p = 0.04). The event-free survival was significantly longer for patients diagnosed after 1986 than before (p = 0.006). Survival was no t significantly affected by radiotherapy or chemotherapy. Children who had had a macroscopically complete excision of the tumor had a 5-year survival of 69% as opposed to 47% for those who had incomplete surger y, but this difference is not significant (p = 0.13). The data suggest that: (1) the event-free survival rate has improved significantly wit h time; (2) there is little correlation between a variety of pathologi cal features and outcome, and (3) failure at the primary site is the m ajor obstacle to improved cure rates. The role of complete resection, including second-look surgery, needs further evaluation.