An innovative method for neuraxis radiotherapy using partial transmission block technique.

Abstract

Whole CNS (neuraxis) radiotherapy is an important part of therapy for certain CNS tumours which seed via the CSF. Many, if not the majority, of these predominantly young patients are cured but the neuropsychometric, neuroendocrine and growth morbidity of neuraxis radiotherapy on children by conventional methods may be considerable; patients receiving such therapy at an early age often are eventually in the educationally subnormal category. Recent radiobiological data support the concept that all aspects of CNS radiation tolerance are heavily dependent on daily fraction size. We describe a new radiotherapy technique that allows lower daily fraction sizes to be delivered to the neuraxis without prejudicing the total dose to the neuraxis or primary area and without prolonging the overall treatment time. Published radiobiological data support the concept that all the major morbidities attributed to conventional neuraxis radiotherapy will be reduced by the currently described technique without reducing tumour control rates.