Related Experiment Video
Updated: Jan 9, 2026
Translational Orthotopic Models of Glioblastoma Multiforme
Published on: February 17, 2023
Pattern of Failure Analysis and Clinical Outcomes in Patients With Grade 2 Meningiomas Following Radiation Therapy
Felix Ehret1, Andrzej Niemierko2, John A Wolfgang2
1Department of Radiation Oncology, Massachusetts General Hospital, Mass General Brigham, Harvard Medical School, Boston, Massachusetts; Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Radiation Oncology, Berlin, Germany; German Cancer Consortium (DKTK), partner site Berlin, a partnership between DKFZ and Charité - Universitätsmedizin Berlin, Germany.
Purpose:
Grade 2 meningiomas often recur after surgery and radiation therapy. However, large, in-depth failure analyses are lacking, limiting the potential to refine radiation therapy. We report a pattern of failure analysis, encompassing treatment and outcome data from over 2 decades.
Methods And Materials:
Patients who underwent proton- or photon-based fractionated adjuvant or salvage radiation therapy for a grade 2 meningioma between 2000 and 2023 were included. Subsequently, an in-depth analysis of the failure pattern was conducted.
Results:
A total of 105 patients were included, with 36 patients having 46 progressive or recurrent grade 2 meningiomas during the available follow-up. Most patients received 59.4 Gy (interquartile range [IQR] 57.6-59.4) in 33 fractions (62.9%) and underwent proton radiation therapy (61.0%), with a median voxel-based equivalent uniform dose (EUD) of 60.1 Gy (IQR, 57.3-61.3). Most recurrent and progressive tumors were either located in the treatment volume (35/46, 76.1%) or within 2 cm of it (9/46, 19.6%). The median distance to out-of-field failures was 11.9 mm. The EUD (hazard ratio [HR], 0.77, 95% confidence interval [CI], 0.59-0.98), target volume (HR, 1.6; 95% CI, 1.2-2.1), RTOG 0539 risk classification (high vs intermediate, HR, 7.9; 95% CI, 1.5-42.7), male sex (HR, 2.0; 95% CI, 0.9-4.4), treatment indication (salvage vs adjuvant, HR, 2.4; 95% CI, 1.1-5.5), and age at radiation therapy (HR, 1.5; 95% CI, 1.0-2.1) were associated with progression.
Conclusions:
This in-depth pattern of failure analysis for grade 2 meningiomas after radiation therapy demonstrated that treatment failures predominantly occur in close spatial relation to the irradiated target volume. Large treatment volumes, macroscopic disease, and a low EUD considerably impact disease control, underscoring the need for further local treatment and targeting refinements.
