case_images: PMC11150652_01
case_images: MRI scans taken on initial admission: (A) coronal T2-weighted FLAIR, (B) axial T2-weighted FLAIR, (C) axial post-gadolinium contrast T1-weighted, and (D) magnetic resonance spectroscopy sequences demonstrating the non-enhancing, expansile right pontine lesion with an increased choline peak suggestive of infiltrating glioma.
case_images: fsurg-11-1356660-g001.jpg
case_images: PMC11150652_01_fsurg-11-1356660-g001.jpg
case_images: F1
case_images: Magnetic resonance imaging (MRI) revealed an ill-defined mass within the right pons that extended into the right middle cerebellar peduncle and the right posterolateral medulla with a corresponding partial effacement of the fourth ventricle suggestive of DIPG (Figure 1).
case_images: Intraoperative photograph of the mass lesion taken during the biopsy.
case_images: fsurg-11-1356660-g002.jpg
case_images: PMC11150652_01_fsurg-11-1356660-g002.jpg
case_images: F2
case_images: Regions of discolored tissue were observed on the floor of the fourth ventricle (Figure 2).
case_images: Representative microscopic features from the intraoperative biopsy sample. (A) H&E sections showed mildly hypercellular white matter with infiltrating atypical glial cells:notably, Rosenthal fibers, eosinophilic granular bodies, microvascular proliferation, and necrosis are absent. (B) Immunohistochemistry for H3 K27M was negative, and (C) the H3 K27 trimethylation (me3) expression was retained in the tumor cells. (D) Ki67 labeling was negative.
case_images: fsurg-11-1356660-g003.jpg
case_images: PMC11150652_01_fsurg-11-1356660-g003.jpg
case_images: F3
case_images: Immunohistochemistry with mutation-specific antibodies against IDH1 R132H and H3K27M was negative, while H3 K27 trimethylation expression was retained (Figure 3).