Adult outcome after treatment of pediatric posterior fossa ependymoma: long-term follow-up of a single consecutive institutional series of 22 patients with more than 5 years of survival.

OBJECTIVE

Ependymoma is the third most common posterior fossa tumor in children; however, there is a lack of long-term follow-up data on outcomes after surgical treatment of posterior fossa ependymoma (PFE) in pediatric patients. Therefore, the authors sought to investigate the long-term outcomes of children treated for PFE at their institution.

METHODS

The authors performed a retrospective analysis of outcome data from children who underwent treatment for PFE and survived for at least 5 years.

RESULTS

The authors identified 22 children (median age at the time of surgery 3 years, range 0-18 years) who underwent primary tumor resection of PFE during the period from 1945 to 2014 and who had at least 5 years of observed survival. None of these 22 patients were lost to follow-up, and they represent the long-term survivors (38%) from a total of 58 pediatric PFE patients treated. Nine (26%) of the 34 children treated during the pre-MRI era (1945-1986) were long-term survivors, while the observed 5-year survival rate in the children treated during the MRI era (1987-2014) was 13 (54%) of 24 patients. The majority of patients (n = 16) received adjuvant radiotherapy, and 4 of these received proton-beam irradiation. Six children had either no adjuvant treatment (n = 3) or only chemotherapy as adjuvant treatment (n = 3). Fourteen patients were alive at the time of this report. According to MRI findings, all of these patients were tumor free except 1 patient (age 78 years) with a known residual tumor after 65 years of event-free survival.Repeat resections for residual or recurrent tumor were performed in 9 patients, mostly for local residual disease with progressive clinical symptoms; 4 patients underwent only 1 repeated resection, whereas 5 patients each had 3 or more resections within 15 years after their initial surgery. At further follow-up, 5 of the patients who underwent a second surgery were found to be dead from the disease with or without undergoing additional resections, which were performed from 6 to 13 years after the second procedure. The other 4 patients, however, were tumor free on the latest follow-up MRI, performed from 6 to 27 years after the last resection. Hence, repeated surgery appears to increase the chance of tumor control in some patients, along with modern (proton-beam) radiotherapy. Six of 8 patients with more than 20 years of survival are in a good clinical condition, 5 of them in full-time work and 1 in part-time work.

CONCLUSIONS

Pediatric PFE occurs mostly in young children, and there is marked risk for local recurrence among 5-year survivors even after gross-total resection and postoperative radiotherapy. Repeated resections are therefore an important part of treatment and may lead to persistent tumor control. Even though the majority of children with PFE die from their tumor disease, some patients survive for more than 50 years with excellent functional outcome and working capacity.