Prognostic significance of contrast enhancement in newly diagnosed glioblastoma, IDH-wildtype in adults

Abstract

Background and Objectives. Glioblastoma, IDH-wildtype presents with a typical ring-like contrast enhanced area surrounding a central necrosis on imaging. We assessed the prognosis of contrast enhancement. Methods. We performed an observational, retrospective, single-centre cohort study at a tertiary neurosurgical oncology centre (January 2006 - December 2022). We screened adult patients harbouring a newly-diagnosed glioblastoma, IDH-wildtype. Results. We included 1149 glioblastomas, IDH-wildtype: 26 (2.3%) had a no contrast enhancement, 45 had a faint and patchy contrast enhancement (4.0%), 118 had a nodular contrast enhancement (10.5%), and 960 had a ring-like contrast enhancement surrounding central necrosis (85.5%). Progression-free and overall survivals were longer in non-contrast enhanced glioblastomas (9.5 months and 26.7 months, respectively) than in contrast enhanced glioblastomas (6.5 months and 10.9 months, respectively) (p = 0.007 and p < 0.001, respectively). Non-contrast enhanced glioblastoma had a higher rate of long-term survivor (42.3%) than in contrast enhanced glioblastoma (16.3%) (p = 0.002). In the subgroup of contrast enhanced glioblastomas, the overall survival was lower in ring-like contrast enhancement (10.0 months) than in other contrast enhancement patterns (13.0 months) (p = 0.033). Cortical involvement by the contrast enhancement and surgical resection were independent predictors of longer survivals, while preoperative KPS score < 70, ventricle involvement of the contrast enhancement, tumour volume ≥ 30cm3, and postoperative residual contrast enhancement were independent predictors of shorter survivals. Conclusion. The ring-like pattern of contrast enhancement is present in the majority (85.5%) of glioblastomas and is associated with shorter survivals than non-contrast enhanced (2.3%) glioblastomas. The pattern of contrast enhancement is an independent survival predictor.