Comparative cross-methodological analysis of the IDH-wildtype glioblastoma tumor microenvironment

PURPOSE: Glioblastoma, IDH-wildtype is a highly aggressive and often recurrent brain malignancy characterized by a profoundly immunosuppressive and heterogeneous tumor microenvironment. In this study, we aimed to systematically compare commonly used immune profiling methodologies. METHODS: We conducted a cross-platform comparison using matched primary and recurrent tumor samples analyzed by immunohistochemistry, multiplex immunofluorescence, AI-driven image analysis, DNA methylation profiling, and bulk RNA sequencing. A total of 72 samples from 36 patients were evaluated to assess cross-method concordance, cell-type resolution, and each platform’s ability to capture TME dynamics throughout disease progression. RESULTS: Across modalities, monocyte/macrophage-lineage cells were the most consistently identified and quantifiable population. Image-based techniques, including immunohistochemistry, multiplex immunofluorescence, and AI-driven quantification, demonstrated strong concordance for B cell and macrophage detection, whereas T cell quantification showed greater inter-method variability, particularly in recurrent tumors. RNA sequencing-based deconvolution captured broader spectrum of immune and neoplastic states, including microglial enrichment, but aligned only moderately with protein-level measurements. DNA methylation-based approaches performed robustly for myeloid cell estimation but limited accuracy for lymphocyte populations. CONCLUSION: This study highlights the complementary strengths and limitations of current immune profiling modalities in GB. An integrative, method-aware framework facilitates more accurate immune cell quantification and deeper biological insights into TME evolution, ultimately informing the development of precision immunotherapeutic strategies for recurrent GB.