Microscopic examination revealed a cellular neoplasm with multiple foci of geographic necrosis. The majority of the cells had large, vesicular nuclei with open chromatin and prominent nucleoli and variable amounts of cytoplasm, ranging from abundant to scarce. Some cells showed the classic rhabdoid appearance with globular cytoplasm and peripheral nuclei. Mitotic figures were common. The majority of the cells seen in the touch prep are rhabdoid, with a peripheral round to oval nucleus, some of them with prominent nucleolus.
Most cells have abundant pink cytoplasm.
A special stain for reticulin demonstrated abundant staining around individual cells as well as bundles of reticulin dispersed throughout the tumor. A panel of immunostains was performed using standard biotin-streptavidin or ABC methods, and the results are shown in Table I. Representative images of immunostains against vimentin , epithelial membrane antigen and GFAP are presented here.