Abstract 4596: BIOhabitats clinical study (NCT05375318): Histopathological analysis of vascular habitats in glioblastoma defined by perfusion MRI

Abstract Tumor heterogeneity is a key hallmark and a major cause of therapeutic resistance in glioblastoma (GBM) patients. To characterize this heterogeneity, the automatic method ONCOhabitats delineate four habitats within the lesion using artificial intelligence analysis of perfusion magnetic resonance imaging (MRI): high angiogenic tumor (HAT), low angiogenic tumor (LAT), infiltrated peripheral edema (IPE), and vasogenic peripheral edema (VPE). BIOhabitats has been successfully implemented in two Spanish hospitals, with the purpose of describing the vascular habitats at histopathological level. To collect samples from each habitat during the standard surgeries, the habitats masks were included in the neuronavigators. Posterior histopathological analyses of each sample were performed. In this preliminary study, we present data from 37 samples from 9 GBMs. Neoplasic cellularity and density of mitosis were evaluated using Mann-Whitney test. In addition, we analyzed the proportion of samples of each habitat from the entire cohort with the presence of necrosis, reactive gliosis, microvascular proliferation (MVP), and glomeruloid vessels. Table 1 includes results analyzing differences among habitats. Our results underline that HAT and LAT are characterized by more proliferative and vascular profiles compared to the edema habitats. However, the IPE habitat presented the highest value of reactive gliosis, which is associated with inflammatory processes and can be related to tumor infiltration. Higher proportions of necrosis, MVP, and glomeruloid vessels were also found in this habitat compared to VPE. Despite this is a preliminary study, we found significant differences among tumor and edema habitats. We highlight the particular histopathological profile of the IPE habitat, different from the active tumor habitats but also from the VPE. BIOabitats is currently in progress including more patients for characterizing the habitats in depth. Table 1. Histopathological analysis among vascular habitats.A) Mann Whitney results of analyzing ne Neoplasic cellularity HAT LAT IPE VPE HAT 1 0.7852 0.0062* 0.0038* LAT 1 0.0047* 0.0030* IPE 1 0.6889 VPE 1 Density of mitosis HAT LAT IPE VPE HAT 1 0.6863 0.0839 0.0087* LAT 1 0.0580 0.0070* IPE 1 0.4667 VPE 1 % of samples with presence HAT LAT IPE VPE Reactive gliosis 46,2 50,0 12,5 0,0 Necrosis 15,4 25,0 100,0 87,5 MVP 84,6 87,5 37,5 12,5 Glomeruloid vessels 38,5 50,0 12,5 0,0 Citation Format: María del Mar Álvarez-Torres, Rebeca Burgos-Panadero, Jaime Agustí Martínez, Carlos Irles Vidal, Jaime Font de Mora, Elies Fuster-Garcia, Juan Miguel García-Gómez. BIOhabitats clinical study (NCT05375318): Histopathological analysis of vascular habitats in glioblastoma defined by perfusion MRI. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4596.