case_images: PMC11783278_01
case_images: (A) Pre-operative T1-weighted post-contrast MRI sequence of the brain demonstrates contrast-enhancing lesions in the cerebellum and right lateral ventricle. (B) Post-operative T1-weighted post-contrast MRI of the brain demonstrates subtotal resection of the right lateral ventricle lesion and persistent enhancing nodules in the cerebellum. (C) Initial MRI of the brain 4 weeks after initial resection demonstrates disease progression, with new right frontal lesion (not pictured) and increased contrast enhancement in cerebellar lesions, an intraventricular lesion, and the surrounding resection cavity. (D) MRI of the brain with and without contrast, following cycle 1 of tepotinib showing near complete resolution of contrast-enhancing disease throughout the brain parenchyma, ventricle, and leptomeningeal space. This response has persisted for 35 months at last follow-up.
case_images: oyae100_fig1.jpg
case_images: PMC11783278_01_oyae100_fig1.jpg
case_images: F1
case_images: April 2020, a male in his late 20s presented with episodes of mild lightheadedness and an intermittent burning odor sensation for 3 years, and new-onset headaches. A brain MRI revealed a right lateral ventricle mass with parenchymal invasion and cerebellar contrast-enhancing nodules (Figure 1a). In May 2020, he underwent subtotal resection, with post-operative imaging showing residual nodular enhancement in the mid-posterior body of the right lateral ventricle and unchanged nodular-enhancing foci in the cerebellum (Figure 1b). A repeat MRI of the neuro-axis was obtained 4 weeks later for radiation treatment planning and showed rapid tumor progression, with multiple new contrast-enhancing nodules in the ventricles and extraventricular cerebrospinal fluid spaces (Figure 1c). Following 1 cycle of tepotinib monotherapy, a brain and spine MRI showed complete resolution of contrast-enhancing lesions (Figures 1d and 2b).
case_images: MRI of the spinal cord with and without contrast (A), initial MRI of the spine, shows punctate contrast-enhancing lesions throughout the thoracic and lumbar spine concerning for leptomeningeal spread. (B) following cycle 1 of tepotinib showing near complete resolution of contrast-enhancing disease throughout the spine's leptomeningeal space. This response has persisted for 35 months at last follow-up.
case_images: oyae100_fig2.jpg
case_images: PMC11783278_01_oyae100_fig2.jpg
case_images: F2
case_images: Because of the intraventricular tumor location, an MRI of the spine was obtained that showed multifocal enhancement in the cervicothoracic spinal cord and cauda equina that was concerning for leptomeningeal spread (Figure 2a). Following 1 cycle of tepotinib monotherapy, a brain and spine MRI showed complete resolution of contrast-enhancing lesions (Figures 1d and 2b).