biostudies-literatureUnknown175(2)Jensen LRNational Hospital<h4>Background</h4>Treatment-refractory meningioma is a widely used term but lacks standardized criteria, impairing research comparability and treatment evaluation. The aim of this study was to assess the heterogeneity of patient populations labeled as treatment-refractory and to explore recommendations for better consistency.<h4>Methods</h4>We systematically reviewed 69 studies published before 2024 and analyzed individual participant data from 15 cohorts (n = 211) that included treatment-refractory patients who underwent experimental therapy with somatostatin receptor (SSTR)-targeted therapies. A reference cohort (n = 102) with newly diagnosed WHO-3 meningiomas was used descriptively for comparison. Progression and death were the primary endpoints. Hazard rate ratios were estimated via PJournal of neuro-oncology599-610https://www.ebi.ac.uk/biostudies/studies/S-EPMC12420741biostudies-literatureThe concept, intention, and evaluation of the term treatment-refractory meningioma.PMC12420741Ruiz-Patino AMaier ADMeling TRBrokinkel BRodriguez AOJuratli TAGraillon TClement PMTorp SHCardona AFBota DARuda RWalter MAGupta TFurtner Jvan Essen MSuh COMunch TNMirian CGoutagny SArrieta OGousias KKristensen BWMathiesen THrachova MScheie DBertero LPreusser MChang JHTabernero MDJensen LRLaw IFugleholm KfalseThe concept, intention, and evaluation of the term treatment-refractory meningioma.<h4>Background</h4>Treatment-refractory meningioma is a widely used term but lacks standardized criteria, impairing research comparability and treatment evaluation. The aim of this study was to assess the heterogeneity of patient populations labeled as treatment-refractory and to explore recommendations for better consistency.<h4>Methods</h4>We systematically reviewed 69 studies published before 2024 and analyzed individual participant data from 15 cohorts (n = 211) that included treatment-refractory patients who underwent experimental therapy with somatostatin receptor (SSTR)-targeted therapies. A reference cohort (n = 102) with newly diagnosed WHO-3 meningiomas was used descriptively for comparison. Progression and death were the primary endpoints. Hazard rate ratios were estimated via P2025-01-01T00:00:00Z2025 Nov2026-06-03T05:47:29.476Z2026-04-25T03:14:51.898ZS-EPMC124207414076031210.1007/s11060-025-05154-2