## 5 Conclusions  
QSI may discriminate tumor-specific patterns of inter-voxel coherence that may represent white matter pathways susceptible to tumor cell invasion, consistent with other recent work showing the prognostic value of features derived from tumor-associated diffusion tractography. The findings of this study contribute to the groundwork for future studies on therapeutic targeting and patient stratification based on alterations in extra-tumoral tissue architecture in glioblastoma. Future studies applying the same imaging and post-processing techniques in human and mice must be conducted to quantitively evaluate the reproducibility and variability of our presented observations across different practice settings and in larger populations. Conceptualization, O.P.L., S.A.T., N.T. and R.J.G. ; Methodology, O.P.L., J.P.Z., S.A.T., D.D.L., N.T. and R.J.G. ; Software, O.P.L., D.D.L. and R.J.G. ; Formal analysis, O.P.L., D.D.L., N.T. and R.J.G. ; Investigation, O.P.L., J.P.Z., M.P., S.A.T., Y.S., N.T. and R.J.G. ; Resources, S.A.T., C.D.F., J.L.B., N.T. and R.J.G. ; Data curation, O.P.L., J.P.Z., Y.D. and J.W. ; Writing-original draft preparation, O.P.L. and R.J.G. ; Writing-review and editing, O.P.L., J.P.Z., M.P., S.A.T., D.D.L., Y.S., Y.D., J.W., R.H., C.C., C.D.F., J.L.B., N.T. and R.J.G. ; Visualization, O.P.L., J.P.Z., N.T. and R.J.G. ; Supervision, S.A.T., N.T. and R.J.G. ; Project administration, O.P.L., S.A.T., N.T. and R.J.G. ; Funding acquisition, S.A.T., C.D.F., N.T. and R.J.G. All authors have read and agreed to the published version of the manuscript. This work was supported in part through grant funding to Dr. [PERSON] and Dr. [PERSON] from the Warren Alpert Foundation. Dr. [PERSON] received related NIH NCI support from the MD Anderson Cancer Center Support Grant (CCSG) via the Radiation Oncology-Cancer Imaging Program (ROCIP)/Image-Driven Biologically-informed Therapy (IDBT) Program (P30 CA016672). The study was conducted in accordance with the Declaration of Helsinki and approved by the Institutional Review Boards of Rhode Island Hospital (IRB #1097531) and University of Texas, M.D. Anderson Cancer Center (IRB #MDACC-RR-03-800). Informed Consent Statement: Informed consent was obtained from all research participants involved in the study. D.D. with Newly Diagnosed and Recurrent Glioblastoma: A Phase 3 Prospective Externally Controlled Cohort Trial. _JAMA Oncol._**2023**, \(9\), 112-121. [CrossRef] [PubMed]
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