This is a retrospective analysis of 16 patients who received PBRT reRT for recurrent meningiomas. The median PBRT dose was 60 Gy(RBE) and the median follow-up was 18.8 months. At last follow-up, 7 intracranial recurrences (44%) and 3 disease-related deaths (19%) were found. Median cohort PFS was 22.6 months, with 1- and 2-year PFS of 80% and 43%, respectively.

Median OS was not achieved, with 1- and 2-year OS of 94% and 73%; all deaths were felt to be related to meningioma. Overall late grade 3+ toxicity rate was 31%. The authors concluded that PBRT reRT achieved fair intracranial control with low rates of radionecrosis at 1 year after reRT. However, strategies to achieve durable outcomes are needed, particularly for high-grade tumors.