case_images: PMC5991284_01
case_images: Preoperative images. Axial CT of the head (a and b) and postcontrast T1WI in the axial plane (c and d), coronal plane (e), and sagittal plane (f). Note that intraventricular mass lesions exist along the choroid plexus
case_images: SNI-9-110-g001.jpg
case_images: PMC5991284_01_SNI-9-110-g001.jpg
case_images: F1
case_images: Computed tomography (CT) showed two hyperdense foci in the inferior horn and the atrium of the right lateral ventricle with peri-lesional edema of the ipsilateral temporo-occipital parenchyma [Figure 1a and b]. T1-weighted imaging (T1WI), on which the lesions appeared to arise from the choroid plexus [Figure 1c-f]. The postcontrast T1WI also showed additional tumor dissemination in the left lateral ventricle and around the brain stem [Figure 1c].
case_images: Postoperative images. Axial postcontrast T1WI (a and b) showing subtotal removal of the intraventricular mass lesions
case_images: SNI-9-110-g002.jpg
case_images: PMC5991284_01_SNI-9-110-g002.jpg
case_images: F2
case_images: The patient was taken to surgery and underwent subtotal removal of the tumor in the right lateral ventricle via an inferior temporal gyrus approach [Figure 2a and b].
case_images: Histopathological features of the tumor. Hematoxylin and eosin staining at 20x magnification (a) and 400x (b), and immunohistochemistry for CD20 at 400x (c) and bcl-6 at 400x (d). Note that the tumor is attached to the choroid plexus (on the right lower part) in (a)
case_images: SNI-9-110-g003.jpg
case_images: PMC5991284_01_SNI-9-110-g003.jpg
case_images: F3
case_images: The tumor was solid, densely adherent to the choroid plexus but floating in the ventricle [Figure 3a]. Histopathologically, the tumor showed diffuse, tightly packed monotonous neoplastic cells with large, round, or slightly irregular nuclei and a scant to moderate amount of eosinophilic cytoplasm [Figure 3b]. On immunohistochemical staining panels, the tumor cells were positive for leukocyte common antigen (LCA), CD20 [Figure 3c], CD30, CD79a, bcl-2, bcl-6 [Figure 3d], and MUM-1; and negative for cytokeratins, epithelial membrane antigen, S-100 protein, and glial fibrillary acidic protein.