Fig. 2

T1 axial postcontrast MRI images a Initial MRI showing left basal ganglia tumor with swollen left thalamus, insula cortex, and hippocampus suggesting multifocal GBM. b Follow up MRI 4 months after primary diagnosis showed an irregular 4.5 cm × 4.0 cm × 5.7 cm (AP x TR x CC) residual tumor. Extensive vasogenic oedema of left frontal lobe was seen extending to left insula, left hippocampal gyrus and body of corpus callosum (arrowhead). Additionally, a smaller ~ 1 cm enhancing lesions are seen, suggestive of local tumor extensions (arrowed). c MRI evaluation at fifth cycle of bevacizumab, carboplatin, and low-dose olaparib revealed shrinkage of left basal ganglia tumor compared to (b). d (2nd craniotomy pre-op) MRI for tumor stereotaxy and surgical planning showed an irregular 1.5 cm × 3 cm tumor mass with predominant peripheral enhancements and central necrosis at left basal ganglia, compressing on the body of the left lateral ventricle