Clear neuroimaging margin at the brain-tumor interface is associated with gross total resection and longer survival in non-enhancing diffuse gliomas.

ABSTRACT

BACKGROUND: This study aimed to determine whether the presence of distinct glioma margins on preoperative imaging is correlated with improved intraoperative identification of tumor-brain interfaces and overall improved surgical outcomes of non-enhancing gliomas. METHODS: This is a retrospective study of all primary glioma resections at our institution between 2000-2020. Tumors with contrast enhancement or with final pathology other than diffuse infiltrative glial neoplasm (WHO II or WHO III) were excluded. Tumors were stratified into two groups those with distinct radiographical borders between tumor and brain, and those with ill-defined radiographical margins. Multivariate analysis was performed to determine the impact of clear preoperative margins on the primary outcome of gross-total resection. RESULTS: Within the study period, 59 patients met inclusion criteria, of which 31 (53%) had distinct margins. These patients were predominantly younger (37.6 vs. 48.1 years, P=0.007). Tumor and other patient characteristics were similar in both cohorts, including gender, laterality, size, location, tumor type, grade, and surgical adjuncts utilized (P>0.05). Multivariate regression identified that distinct preoperative margins correlated with increased rates of gross total resection (P=0.02). Distinct margins on preoperative neuroimaging also correlated positively with surgeon identification of intra-operative margins (P<0.0001), fewer deaths over the study period (P=0.01), and longer overall survival (P=0.03). CONCLUSIONS: Distinct glioma-parenchyma margins on preoperative imaging are associated with improved surgical resection for diffuse gliomas, as distinct margins may correlate with distinguishable glioma-brain interfaces intraoperatively. Further prospective studies may discover additional clinical uses for these findings.