P13.04.B Dissecting high-grade glioma immune infiltration in samples from fluorescence-guided surgery: digital pathology with automated image analysis

Abstract Background Fluorescence-guided surgery with 5-aminolevulinic acid (5-ALA) is a widely used technique to conduct maximum safe resection of high-grade gliomas (HGG). 5-ALA accumulates in malignant tumor tissue where it metabolized Protoporphyrin IX (PpIX), an agent fluorescence properties. It helps neurosurgeons distinguish between tumor-infiltrated and healthy brain parenchyma. Even though fluorescence-guided clinically well established, the biological properties different levels are not comprehensively studied yet. A relevant current gap that respect pattern immune cell infiltration fluorescent versus non-fluorescent samples. In light future research, reliable, standardized histopathology methods allow high-throughput analysis desirable digital pathology automated image attractive option explore. Material Methods 128 formalin-fixed paraffin-embedded (FFPE) blocks 39 patients who underwent HGG were included. Samples selected based on their documented intensity status (strong, vague, negative). Microtome-cut sections stained antibodies against CD8, CD68, CD163 FOX P3, representing populations specific interest (cytotoxic T cells, glioma-associated macrophages, regulatory cells). total 512 slides then available for assessment. addition classical, semi-quantitative by two independent human reviewers, was measured via software QuPath Version 0.3.2. Results Across all FFPE samples CD68 showed overall highest intensity, followed CD163. CD8 FoxP3 generally lower average intensities. negative positive glioma same. Quantitative automatic correlated classical histopathological majority markers evaluated. Conclusion We successfully explored established novel technologies study patterns neurooncology, specifically context resection. Leveraging this platform could parallelized also other contexts.