Role of radiotherapy in anaplastic ependymoma in children under age of 3 years: results of the prospective German brain tumor trials HIT-SKK 87 and 92.

Background and Purpose: To evaluate the outcome of very young children with anaplastic ependymoma after delayed or omitted radiotherapy (RT).
Materials and Methods: Children under age of 3 years with anaplastic ependymoma were enrolled in the HIT-SKK 87 trial from 1987. After surgery, low-risk patients (R0, M0) received maintenance chemotherapy until elective RT at age of three. In high-risk patients (R+, M+) intensive induction chemotherapy was followed by maintenance chemotherapy and subsequently delayed RT. If there was, progression radiotherapy started immediately. In the HIT-SKK 92, trial MTX-based chemotherapy was applied. RT was administered in non-responders only.
Results: Thirty-four children with anaplastic ependymoma were eligible (age 1.0-33.0 months). All children received chemotherapy. In 13 children, no RT was administered. Preventive RT after chemotherapy was given in nine, and salvage RT in 12 children. OS and PFS rates after 3-year were 55.9 and 27.3%, respectively. Twenty-five children relapsed. Positive impact on survival was observed in children with higher age, M0-stage, complete resection, and treatment with radiotherapy. Without RT only 3/13, children survived.
Conclusion: Delaying RT jeopardizes survival even after intensive chemotherapy. Predominant site of failure is the primary tumor site. RT of the neuraxis should be omitted in localized disease.