Most glioblastomas will recur, and it isn’t uncommon to need to consider reirradiation. Here are recommendations from ESTRO/EANO for reirradiating GBM. Eligible patients should have a good performance status and at least 6 months since the initial course of radiation. The target is typically limited to gross disease visible on T1 with contrast, and either no or a small 3-5mm CTV margin can be used. A dose of at least 36 Gy EQD2 is recommended with preferred regimens of 27-30 Gy in 3-5 fractions for smaller targets and 35 Gy in 10 fractions for moderate to large targets. | Andratschke, Radiother Oncol 2024
