ACNS0121: conformal radiotherapy for paediatric ependymoma, chemotherapy for incompletely resected tumours and observation after complete resection
In the largest trial of childhood ependymoma, radiotherapy focused on the tumour bed straight after surgery cured about two thirds of children, worked as well in those under three as in older children, and children whose tumour could not be fully removed fared much worse.
Overview
Children's Oncology Group phase 2 trial of 378 children aged 1 to 21 with newly diagnosed ependymoma, assigned by extent of resection and histology to observation (complete resection of differentiated supratentorial tumours), immediate post-operative conformal radiotherapy (near-total or gross-total resection) or chemotherapy before second surgery and radiotherapy (subtotal resection).
Five-year event-free survival was 68.5 percent after immediate conformal radiotherapy, 61.4 percent with observation and 37.2 percent after subtotal resection. Outcomes differed by tumour grade but not by age, location, RELA fusion or posterior fossa subgroup; 1q gain predicted relapse in infratentorial tumours (five-year event-free survival 47.4 against 82.8 percent).
- Five-year event-free survival 68.5 percent (95% CI 62.8 to 74.2) with immediate conformal radiotherapy, 61.4 percent with observation, 37.2 percent after subtotal resection.
- No difference in event-free survival by age, so children under three benefit from immediate radiotherapy.
- 1q gain in infratentorial tumours: five-year event-free survival 47.4 versus 82.8 percent (p 0.0013).
Maximal resection followed by conformal radiotherapy is the mainstay for most childhood ependymoma, including in very young children; incompletely resected tumours need better approaches.
- Non-randomised assignment by resection status.
- The observation arm was small and its confidence interval wide.