Hypofractionated radiotherapy of central nervous system tumours: Current thoughts in 2025

The use of hypofractionated radiotherapy for central nervous system tumours is expanding, particularly due to the increase in reirradiation situations. This article reports a reflection on its use for neurological tumours through five questions illustrated by non-exhaustive clinical examples. Why? We explored the rationale of hypofractionation and its benefits. For whom? We reviewed the different recommendations on indications including patients and tumours which would benefit more of hypofractionation. How? Treatment planning must be careful and adapted to this specific technique, especially in reirradiation cases, and when systemic therapies are involved. When? Timing is the essence, it can be used exclusively, combined with systemic treatment, prior to or after surgery… Why not? Hypofractionation is not suitable for all central nervous system tumours, it may even be contraindicated in some cases.