Aggressive surgery followed by targeted radiotherapy is the optimal means by which a rare form of childhood brain cancer should be treated, conclude the authors of an Article published Online First and in the March issue of The Lancet Oncology.
Ependymoma is a rare type of tumour that affects the central nervous system. Although aggressive surgical intervention has proved successful in treating such tumours in older patients, concern over side-effects has limited the take-up of radiation therapy in children with the disease.
However, recent developments in neurosurgery and in the administration of radiation led Dr Thomas Merchant (St Jude Children's Research Hospital, TN, USA) and colleagues to begin to treat children with localised ependymoma with aggressive surgery followed by computer-guided (conformal) radiation therapy.
In this study, Merchant and colleagues report outcomes for 153 children treated in this manner, including, for the first time, children under the age of 3 years. The children were then followed up for a median duration of 5•3 years (range 0•4��•4). 23 patients died; tumour progression was reported in 36 patients. The researchers estimate that event-free survival at 7 years would be 69•1% (95% CI 56•9��•3), and overall survival 81•0% (71•0��•0). Local tumour control was better than expected, with a 7-year estimate of 87•3% (77•5��•1). Treatment was generally well tolerated. Patients who underwent radiation therapy without delay after surgery showed even better event-free survival (76•9% [95% CI 63•4-90•4]) and overall survival (85•0% [74•2��•8]). Although there was no control group in this trial, these rates compare favourably with those achieved in other studies.
Merchant comments that "This study highlights the long-term benefits…of gross total resection and high-dose post-operative radiotherapy for the treatment of children with localised ependymoma, even for those who are younger than 3 years". He adds that "newer methods of radiotherapy delivery promise further reductions in the dose [delivered] to healthy tissue" to further reduce radiotherapy-related side-effects, and "provides unique insight into the role of radiation therapy in the initial management of young children, and that future efforts to combat ependymoma should also prioritise increasing the rate of gross total resection".
Dr Thomas E Merchant, Department of Radiological Sciences, St Jude Children's Research Hospital, Memphis, T) +1 901 595 3604. E) Thomas.merchant@stjude.org
For full Article see: http://press.thelancet.com/TLOpaedependymoma.pdf
Notes for editors
In this study, the aim of aggressive surgery was to achieve gross-total resection, defined as macroscopically complete resection of the tumour with no evidence of residual tumour on MRI.
In this study, CT and MRI scans were taken of each patient to target the site at which radiotherapy would be administered to within 10 mm of the site of tumour, so as to reduce delivery of radiation to healthy tissue. The intensity of the radiotherapy was also modulated to reduce the dose delivered to sensitive tissues (eg, eyes, ears). 22 patients were given a total dose of 54•0 Gy, while the remaining 131 patients received 59•4 Gy
Journal
The Lancet Oncology