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Posterior fossa ependymomas in children: still a challenge for pediatric neurosurgeons and oncologists.

Introduction: Posterior fossa ependymomas in children are associated with a poor prognosis. This retrospective study tries to determine prognostic factors for the outcomes and the quality of life. Material and Methods: Thirty-three patients with posterior fossa ependymomas were treated from 2002 to 2018. All patients had a cranio-spinal MRI and 3.12% were metastatic. Removal was complete in 29 patients (90.62%). All patients received a complementary treatment: 11patients chemotherapy, radiotherapy in 35 patients, 24 cases of neoadjuvant type and for recurrence in 11. Results: Average age was 5.8 years with a range from 9 months to 18 years. The sex ratio was 2.3 (M/F: 23/10). Sixteen patients had one recurrence (3 metastatic). 90% of the EpPCF were of the PFA group. Overall Survival was 65% with a mean follow-up of 8.4 and a median of 9 years. Twenty-one patients were alive (63.63%) at last follow-up. All were tumour-free according the MRI except 2 patients, 1 with a stable residue for 5 years and 1 in palliative treatment for metastatic recurrence for 5 years. Post-operative complications were as follow, facial nerve palsy in four cases (12.12%), swallowing disorders in three cases (9.09%), transient cerebellar syndrome in 4 cases (12.12%). Fifteen patients had normal schooling. Conclusion: Posterior fossa ependymomas are aggressive tumors. Complete surgical removal remains the most important prognostic factor even if responsible of sequels. Despite molecular studies and the expression of different genes, no obvious therapeutic target has yet emerged.