EPN-38
RELAPSE PATTERNS IN PEDIATRIC INTRACRANIAL EPENDYMOMA: A CANADIAN EXPERIENCE

BACKGROUND: Ependymomas represent 9% of childhood brain tumors with management algorithms heavily influenced by single-institution experiences. METHODS: Fourteen of 16 Canadian Pediatric Brain Tumour Consortium (CPBTC) centers performed a retrospective study of children less than 18 years of age with intracranial ependymoma from 1986-2006. Relapse patterns and outcome were evaluated. Ethics approval was obtained. RESULTS: There were 210 (139 M: 71F) intracranial ependymoma cases, 46% (92) <= 4 years. The median age was 3.66 years (0.4 -17.7). 53% (112/210) experienced a first relapse with median time to relapse 1.4 years (0.1 to 6.1). 70% (146/210) gross total resection (GTR) at diagnosis with adjuvant radiotherapy in 77% (162/210). Isolated local recurrence (IR) noted in 54% (61/112), dissemination (LM) in 44% (49/112). Salvage approaches included incomplete resection in 28, and GTR in 43. Re-irradiation was a component of therapy in 12 survivors, median follow-up 5 yrs (2-16). 19/61 IR are alive at last follow-up. Of the LM group at relapse (31M: 18F), 90% (44/49) arose from the posterior fossa (PF) and 53% (26/49) were WHO grade 3. 24% (12/49) of the LM relapse group are alive at last follow-up with a median follow-up of 4.31 years (0.08 to 16.1). Salvage included: surgery (2), surgery and radiotherapy (6), chemotherapy (2), surgery, radiotherapy and chemotherapy (1), and radiation (1). 72% succumbed to childhood ependymoma following first relapse. CONCLUSIONS: The incidence of LM at relapse was 23%, one quarter of LM and one third of IR are alive following relapse therapy.